G3488A SCD and G3489A NCD User Manual
Agilent 8355 Sulfur and
8255 Nitrogen
Chemiluminescence
Detectors
User Manual
Agilent Technologies
Notices
© Agilent Technologies, Inc. 2016
Warranty
No part of this manual may be reproduced
in any form or by any means (including
electronic storage and retrieval or
translation into a foreign language)
without prior agreement and written
consent from Agilent Technologies, Inc. as
governed by United States and
international copyright laws.
The material contained in this document
is provided “as is,” and is subject to
being changed, without notice, in future
editions. Further, to the maximum extent
permitted by applicable law, Agilent
disclaims all warranties, either express
or implied, with regard to this manual and
any information contained herein,
including but not limited to the implied
warranties of merchantability and fitness
for a particular purpose. Agilent shall not
be liable for errors or for incidental or
consequential damages in connection
with the furnishing, use, or performance
of this document or of any information
contained herein. Should Agilent and the
user have a separate written agreement
with warranty terms covering the
material in this document that conflict
with these terms, the warranty terms in
the separate agreement shall control.
Manual Part Number
G3488-90010
Edition
Fourth edition, February 2016
Third edition, December 2015
Second edition, October 2015
First edition, September 2015
Printed in USA or China
Agilent Technologies, Inc.
2850 Centerville Road
Wilmington, DE 19808-1610 USA
安捷伦科技 (上海)有限公司
上海市浦东新区外高桥保税区
英伦路 412 号
联系电话:(800)820 3278
Safety Notices
CAUTION
A CAUTION notice denotes a hazard.
It calls attention to an operating
procedure, practice, or the like that, if
not correctly performed or adhered to,
could result in damage to the product
or loss of important data. Do not
proceed beyond a CAUTION notice
until the indicated conditions are fully
understood and met.
WA R N I N G
A WARNING notice denotes a hazard.
It calls attention to an operating
procedure, practice, or the like that, if
not correctly performed or adhered
to, could result in personal injury or
death. Do not proceed beyond a
WARNING notice until the indicated
conditions are fully understood and
met.
Contents
1
Getting Started
Manuals, Information, Tools and Where to Find Them
GC Manuals, Tools, and Online Help 8
User Apps
14
Education Opportunities
17
2
Overview of the 8355 SCD and 8255 NCD
18
Overview of Installation and First Startup
22
8
Safety and Regulatory Information
Introduction
24
Important Safety Information
25
Many internal parts of the detector carry dangerous voltages
Electrostatic discharge is a threat to GC electronics 26
Many parts are dangerously hot 26
Hydrogen safety 26
Ozone
28
Oxygen environments 28
Symbols
Fuses
29
30
Safety and Regulatory Information 31
Sound Emission Certification for Federal Republic of Germany
Schalldruckpegel 32
Electromagnetic compatibility
32
Intended Use
Cleaning
32
34
34
Recycling the Product
Technical Assistance
SCD and NCD User Manual
25
34
34
3
3
System Description
Specifications
8355 SCD
8255 NCD
36
36
36
Theory of Operation
SCD
37
NCD
37
37
Description of Major Components
39
Burner assembly
39
Ozone generator
41
Reaction cell and photomultiplier tube (PMT)
EPC modules
42
Vacuum pump 42
Ozone destruction trap
42
Oil coalescing filter
42
FID adapter (optional) 42
NCD chiller 43
4
42
Operation
Introduction 46
Integrated version
46
Setting Parameters 47
Parameters and ranges
47
Software control 48
GC keyboard control 50
Identifying the detector
50
Detector Stability and Response
Typical Operating Conditions
51
52
Adjusting the Operating Conditions
Start-up
54
Resource Conservation
Shutdown
55
56
Configure Auto Flow Zero on the GC
Configure the Detector
4
53
57
58
SCD and NCD User Manual
5
Maintenance
Maintenance Log and Early Maintenance Feedback (EMF)
Maintenance Schedule
63
Tracking Detector Sensitivity
64
Consumables and Replacement Parts
Exploded Parts View of the SCD
67
Exploded Parts View of the NCD
68
Detector Maintenance Method
70
Replace the Inner Ceramic Tube (SCD)
Replace the Quartz Tube (NCD)
73
76
Check the Vacuum Pump Oil
Add Vacuum Pump Oil
65
69
Attach a Column to the Detector
80
81
Replace the Vacuum Pump Oil
Replace the Ozone Trap
83
85
Change the Oil Mist Filter
87
Clean the Detector Exterior
88
Calibrate the Flow and Pressure Sensors
Updating Firmware
6
62
89
90
Troubleshooting
Solving Detector Problems
Troubleshooting Table
93
Status Indicator LED
Detector Messages
92
96
97
Leaks
98
Ozone leaks
98
Hydrogen leaks 98
Oxidizer leaks 98
Checking for hydrogen and oxidizer leaks
99
Power Problems 100
No power
100
Ozone Generation Problems
SCD and NCD User Manual
101
5
Coking
7
102
Hydrogen Poisoning
103
Contaminated Gases
104
Performance Verification
About Chromatographic Checkout
106
Prepare for Chromatographic Checkout
Prepare sample vials
108
6
Check SCD Performance
109
Check NCD Performance
114
107
SCD and NCD User Manual
Agilent 8355 SCD and 8255 NCD
User Manual
1
Getting Started
Manuals, Information, Tools and Where to Find Them 8
Overview of the 8355 SCD and 8255 NCD 18
Overview of Installation and First Startup 22
This chapter introduces the Agilent 8355 Sulfur
Chemiluminescence Detector (SCD) and the Agilent 8255
Nitrogen Chemiluminescence Detector (NCD), and provides
details about where to find helpful information and tools, such
as GC manuals, flow calculators, and so forth.
Agilent Technologies
7
1
Getting Started
Manuals, Information, Tools and Where to Find Them
This manual describes how to operate the Agilent 8355 Sulfur
Chemiluminescence Detector (SCD) and the Agilent 8255
Nitrogen Chemiluminescence Detector (NCD) as installed on an
Agilent 7890B Gas Chromatograph (GC). This manual also
provides operating recommendations, maintenance procedures,
and troubleshooting. For installation instructions, see the
Agilent 8355 SCD and 8255 NCD Installation and First Startup
Guide. To prepare the installation site for a new SCD or NCD,
see the Agilent 8355 SCD and 8255 NCD Site Preparation
Guide.
In addition, Agilent provides other manuals, familiarization
information, and help systems for self-paced learning about the
7890B GC. You will need to reference this general GC
information for installation and operation of the detector. The
sections below describe this information and where to find it.
GC Manuals, Tools, and Online Help
Agilent provides several learning products that explain how to
install, operate, maintain, and troubleshoot the 7890B GC
system. These manuals can be found on the Agilent GC and
GC/MS User Manuals & Tools DVDs that are included with your
GC shipment.
Installing your manuals provides for a much richer user
experience by providing the ability to install the manuals you
want, in the language you want. Install HTML and PDF versions.
8
SCD and NCD User Manual
Getting Started
1
Agilent Technologies
GC/GCMS Hardware User Manuals and Videos
Version B.01.05
Disk 2/3
Agilent Technologies
January, 2013
GC/GCMS Hardware User
To install: Manuals and Videos
Version B.01.05
January, 2013
S1N
1. Insert disk into DVD drive
2. Follow the instructions on the screen.
3. If autoplay is not enabled, double-click
"index_xx.html" on the DVD
where xx is:
en for English
ch for 中文
jp for 日本語
To install:
1. Insert disk into DVD drive
2. Follow the instructions on the screen.
© 2013 Agilent Technologies, Inc.
3. If autoplay is not enabled, double-click
All rights reserved.
"index_xx.html" on the DVD
where xx is:
Made in USA
en for English
ch for 中文
jp for 日本語
Disk 2/3
© 2013 Agilent Technologies, Inc.
All rights reserved.
Made in USA
S1N
Select the Instrument Manuals icon
from the GC and GC/MS User Manuals
& Tools DVD and install the suite of
manuals for your system.
SCD and NCD User Manual
9
1
Getting Started
Available manuals
Table 1
7890B GC Learning Products
Learning product
Contents
When to use this documentation
Getting Started
Overview of the manuals. Where to
find information. How to install the
manuals. Overview of the GC.
Safety Manual
Lists safety and regulatory
information. Precautions for using
hydrogen carrier (or fuel) gas.
Precautions for performing
maintenance tasks.
• Before installation, to prepare for a
GC, GC/MS, and ALS Site Prep Guide
Requirements for: space and weight
for the lab bench, power, heat
dissipation, exhaust venting,
laboratory conditions (expected local
environment), gas and reagent gas
purity, gas supplies, gas plumbing
(including filters, regulator types, and
tubing needs), and cryogenic cooling
supplies (if used).
Recommended supplies to purchase
before installation.
• Before installation, to prepare the
Installation and First Startup
How to install the GC on the
laboratory bench. Cabling pinouts.
• During installation.
Operation Manual
Common keyboard functions. Using
the keyboard to start runs and
sequences. Using the keyboard when
connected to an Agilent data system.
Methods and sequences overview.
Startup and shutdown. How to check
GC performance after installation.
Energy conservation (sleep/wake).
Early Maintenance Feedback.
Configuration.
• To learn common operating tasks
safe installation process.
• Before maintenance.
laboratory site.
• Before installation, to find what
supplies are needed for successful
installation (such as gases,
installation kits, gas purifiers,
regulators, tubing, fittings,
consumable parts, and so on).
• At any time, to refer to expected
requirements for gas supplies,
regulators, cryogenic cooling
supplies, supply pressures, and so
on.
•
•
•
•
•
10
(making a run, loading a method,
running a series of samples).
To learn how to use the GC keyboard
when under data system control.
Before a short-term or long-term
shutdown.
When starting up the GC after a
period of inactivity.
Whenever you need to verify
performance of the instrument
against factory standards, for
example, after certain maintenance
procedures.
To learn how to properly configure GC
components, especially when newly
installed.
SCD and NCD User Manual
Getting Started
Table 1
1
7890B GC Learning Products
Learning product
Contents
When to use this documentation
Advanced Operation Manual
Procedures and theory of operation
not normally required for daily use:
programming; detailed information
about methods and sequences; inlet
(column) flow and pressure modes;
inlet, detector, valve, oven, and other
setpoint details; and output signal
settings.
• When developing methods.
• When running the GC standalone (no
Procedures to maintain the GC,
including procedures for all standard
inlet and detector options.
Replacement parts information.
Instructions for using Early
Maintenance Feedback (EMF).
• To look up a replacement part or
Troubleshooting
Procedures for resolving GC issues.
Symptoms and resolutions for
resolving GC or chromatographic or
hardware issues. Procedures to
determine whether an issue is
hardware-related, software-related, or
related to other factors (such as
sample preparation).
• When trying to isolate the cause of
GC Software Familiarization
• To locate settings in the data system
Introduction to the data system
user interface.
control software user interface for the
GC. Introduces concepts for EMF and
configuration, and other new features.
Data system help
Topics and tasks for creating and
editing methods for the GC.
Maintaining Your GC
data system).
• To learn details about settings.
consumable part.
• Before performing any maintenance
on the GC.
unexpected performance issues.
• To answer questions about using the
software to control the GC.
Language Versions
Agilent provides the 7890B learning products in several
languages. Table 2 below lists the manuals and the languages
available for each manual format (print, Adobe PDF, or HTML).
SCD and NCD User Manual
11
Getting Started
HTML
PDF
Safety Manual
HTML
PDF
Installation and First Startup
HTML
PDF
GC, GC/MS, and ALS Site Prep Guide
HTML
PDF
Maintaining Your GC
HTML
PDF
Troubleshooting
HTML
PDF
9 9
9 9
9 9
9
Russian
Brazilian Portuguese
Japanese
Print
Italian
Getting Started
German
Format
Spanish
Manual
French
Languages available for GC manuals
Chinese
Table 2
English
1
9 9 9 9 9 9 9 9 9
9 9
9
9 9 9 9 9 9 9 9 9
9 9
9
9 9 9 9 9 9 9 9 9
9 9
9
9 9 9 9 9 9 9 9 9
9 9
9
9 9 9 9 9 9 9 9 9
9 9
9
9 9 9 9 9 9 9 9 9
12
SCD and NCD User Manual
Getting Started
PDF
Advanced Operation Manual
HTML
PDF
Software Familiarization
HTML
9 9
Russian
Brazilian Portuguese
Japanese
Italian
HTML
German
Operation Manual
French
Format
Spanish
Manual
Chinese
Languages available for GC manuals
English
Table 2
1
9
9 9 9 9 9 9 9 9 9
9
9
9 9
9 9 9
Online help
In addition to hardware manuals, your GC data system also
includes an extensive online help system with detailed
information, common tasks, and video tutorials on using the
software.
SCD and NCD User Manual
13
1
Getting Started
User Apps
In addition to the Hardware Manuals, you will also find several
User Apps on the Agilent GC and GC/MS User Manuals & Tools
DVDs. See below for a list of available Apps, such as Parts
Finder, the GC Firmware Update Tool, and a variety of Method
Developer Tools.
14
SCD and NCD User Manual
Getting Started
1
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SCD and NCD User Manual
15
1
Getting Started
Install the GC Firmware
Update tool to install
WKHODWHVWÀUPZDUHRQWR
your GC and sampler
systems.
Install Method Developer
Tools, such as the
Method Translator, to
help you convert a
helium carrier gas
method to use hydrogen.
16
SCD and NCD User Manual
Getting Started
1
Education Opportunities
Agilent has designed customer courses to help you learn how to
use your GC to maximize your productivity while learning about
all of the great features of your new system:
R1778A — Agilent 7890 A/B GC and OpenLAB ChemStation
Operation
R1914A — Agilent 7890 A/B GC Troubleshooting and
Maintenance
R2255A — Agilent 7890 Series GC Operation with OpenLAB
EZChrom
For course details and education opportunities, visit
http://www.agilent.com/chem/education, or call your local Agilent
sales representative.
SCD and NCD User Manual
17
1
Getting Started
Overview of the 8355 SCD and 8255 NCD
Figure 1 through Figure 5 show the controls, parts, and
components of the 8355 SCD and 8255 NCD used or accessed
during installation, operation, and maintenance.
Status LED
Power switch
Power switch
8355 SCD
Figure 1
18
Status LED
8255 NCD
Front view, detector (SCD and NCD)
SCD and NCD User Manual
Getting Started
Burner heater
connector
1
Hydrogen gas input
Oxidizer gas input
Heater/sensor
connector
Ozone gas input
Through-hole for
sample transfer line
Thermocouple
connector
Communications
cable
Vacuum connection
Power connection
Vacuum pump
power connection
Figure 2
Detector back view
SCD and NCD User Manual
19
1
Getting Started
Hydrogen gas input
Upper hydrogen output
(SCD only)
Oxidizer gas input
Oxidizer gas output
Ozone gas input
Lower hydrogen output
Figure 3
Detector gas connections
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plug
Figure 4
20
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Pump oil pan
RV5 Vacuum pump
SCD and NCD User Manual
Getting Started
1
Maximum oil level
mark
Sight gage
Oil level
Minimum oil level
mark
Figure 5
SCD and NCD User Manual
RV5 Vacuum pump oil sight gage
21
1
Getting Started
Overview of Installation and First Startup
Below is an overview of the installation process. See the
Installation and First Startup Guide for complete installation
details.
1 If not already installed, install the GC and Agilent data
system. (If another detector is present, verify its
performance.)
2 Place the detector on the bench. Remove protective caps.
3 Prepare the GC. Cool the GC, then turn off and unplug the
power cord. Remove covers.
4 Prepare the detector mounting location.
5 Unpack the vacuum pump. Remove plugs. Install oil
coalescing filter and ballast.
6 Install the vacuum pump.
7 Verify the power configuration.
8 Install the burner assembly.
9 Connect the supply gases.
10 Connect the detector gases.
11 Connect the detector cables and wires.
12 Connect cables to the GC and detector.
13 Connect to power.
14 Install the column.
15 Install the GC covers.
16 Turn on the GC and the detector.
17 Configure the detector.
18 Create a checkout method and verify performance.
22
SCD and NCD User Manual
Agilent 8355 SCD and 8255 NCD
User Manual
2
Safety and Regulatory Information
Introduction 24
Important Safety Information 25
Symbols 29
Fuses 30
Safety and Regulatory Information 31
Intended Use 34
Cleaning 34
Recycling the Product 34
Technical Assistance 34
This chapter provides important safety and regulatory
information required for installation and use of the Agilent
8355 SCD and the Agilent 8255 NCD. Read and understand this
information before operating the detector.
Agilent Technologies
23
2
Safety and Regulatory Information
Introduction
This manual will guide you in the operation, maintenance, and
troubleshooting of the Agilent 8355 SCD and the Agilent 8255
NCD. The SCD and NCD are typically installed onto the gas
chromatograph (GC) by Agilent-trained personnel. If installing
the SCD or NCD, see the Installation Guide for instructions.
In addition to the information here, refer to the GC safety
information that shipped with the GC. Find the Agilent GC
manuals on the Agilent Technologies GC and GC/MS User
Manuals & Tools DVDs.
24
SCD and NCD User Manual
Safety and Regulatory Information
2
Important Safety Information
There are several important safety notices that you should
always keep in mind when using the 8355 SCD or 8255 NCD.
Many internal parts of the detector carry dangerous voltages
If the GC and detector are connected to a power source, even if
the power switches are off, potentially dangerous voltages exist
on the:
• Wiring between the detector power cord and the AC power
supply
• AC power supply
• Wiring from the AC power supply to the power switch.
With the power switches on, potentially dangerous voltages also
exist on:
• All electronics boards.
• The internal wires and cables connected to these boards.
Note that the GC supplies power to the detector electronics
boards and EPC modules.
SCD and NCD User Manual
25
2
Safety and Regulatory Information
Electrostatic discharge is a threat to GC electronics
The printed circuit (PC) boards in the detector can be damaged
by electrostatic discharge. Do not touch any of the boards unless
it is absolutely necessary. If you must handle them, wear a
grounded wrist strap and take other antistatic precautions.
Wear a grounded wrist strap any time you must remove the GC
right side cover, or the right or left side detector covers.
Many parts are dangerously hot
Many parts of the detector operate at temperatures high enough
to cause serious burns. These parts include, but are not limited
to:
• The dual plasma burner
• The detector interface to the GC, including the column
connection
Always cool these areas of the detector to room temperature
before working on them. If you must perform maintenance on
hot parts, use a wrench and wear thermally protective gloves.
Whenever possible, cool the part of the instrument that you will
be maintaining before you begin working on it.
Hydrogen safety
Hydrogen gas is used as a fuel gas to produce a flame in the
detector.
WA RNING
26
When using hydrogen (H2) as a fuel gas, be aware that hydrogen
gas can flow into the GC oven and create an explosion hazard.
Therefore, be sure that the supply is turned off until all
connections are made and ensure that the detector column
fittings are either connected to a column or capped at all times
when hydrogen gas is supplied to the detector. Hydrogen is
flammable. Leaks, when confined in an enclosed space, may
create a fire or explosion hazard. In any application using
hydrogen, leak test all connections, lines, and valves before
operating the instrument. Always turn off the hydrogen supply at
its source before working on the instrument.
SCD and NCD User Manual
2
Safety and Regulatory Information
Hydrogen is a commonly used GC carrier gas. Hydrogen is
potentially explosive and has other dangerous characteristics.
• Hydrogen is combustible over a wide range of
concentrations. At atmospheric pressure, hydrogen is
combustible at concentrations from 4 % to 74.2 % by volume.
• Hydrogen has the highest burning velocity of any gas.
• Hydrogen has a very low ignition energy.
• Hydrogen that is allowed to expand rapidly from high
pressure into the atmosphere can self-ignite due to an
electrostatic spark.
• Hydrogen burns with a nonluminous flame which can be
invisible under bright light.
Hydrogen shutdown
Hydrogen gas is used as a fuel for the SCD and NCD detectors.
When using the detector with an Agilent 7890B or 7890A+ GC,
the GC monitors any hydrogen gas streams. If a stream shuts
down because it is unable to reach its flow or pressure setpoint,
and if that stream is configured to use hydrogen, the GC
assumes that a leak has occurred and declares a hydrogen
safety shutdown.
If the GC goes into hydrogen safety shutdown, the effects for the
detector are:
• The detector heated zones are turned off.
• The detector hydrogen flows are shut off.
• The ozone generator is turned off.
• The vacuum pump remains on.
To recover from this state, fix the cause of the shutdown (tank
valve closed, serious leak, others). Turn the instrument and
detector off, then back on.
WA RNING
SCD and NCD User Manual
The GC cannot always detect leaks in detector gas streams. For
this reason, it is vital that column fittings should always be either
connected to a column, or have a cap or plug installed. The H2
streams must be configured for hydrogen so that the GC is aware
of hydrogen use.
27
2
Safety and Regulatory Information
Measuring hydrogen gas flows
WA RNING
Do not measure hydrogen together with air or oxygen. This can
create explosive mixtures that may be ignited by the automatic
igniter. To avoid this hazard: 1. Turn the automatic igniter off
before you begin. 2. Always measure gases separately.
When measuring gas flows on a detector using hydrogen for the
detector flame or GC carrier gas, measure the hydrogen flow
separately. Never allow an air stream to enter when hydrogen is
present in the flow meter.
Ozone
WA RNING
Ozone is a hazardous gas and a strong oxidant. Exposure to ozone
should be minimized by using the instrument in a well-ventilated
area and by venting the exhaust of the vacuum pump to a fume
hood. The ozone generator should be turned off when the
instrument is not in use.
Oxygen environments
WA RNING
28
Oxygen rich environments can promote combustion, and even
result in spontaneous combustion under conditions of high
pressure and exposure to contamination. Use only oxygen-rated
components, and ensure that components are oxygen clean prior
to use with pure oxygen.
SCD and NCD User Manual
Safety and Regulatory Information
2
Symbols
Warnings in the manual or on the instrument must be observed
during all phases of operation, service, and repair of this
instrument. Failure to comply with these precautions violates
safety standards of design and the intended use of the
instrument. Agilent Technologies assumes no liability for the
customer’s failure to comply with these requirements.
See accompanying instructions for more
information.
Indicates a hot surface.
Indicates hazardous voltages.
Indicates protective conductor terminal.
Indicates potential explosion hazard.
Indicates electrostatic discharge hazard.
Indicates a hazard. See the Agilent user
documentation for the item labeled.
Indicates that you must not discard this
electrical/electronic product in domestic
household waste
SCD and NCD User Manual
29
2
Safety and Regulatory Information
Fuses
The 8355 SCD and 8255 NCD require fuses for proper operation.
These must only be accessed by Agilent trained service
personnel.
WA RNING
For continued protection against fire hazard, replace fuses only
with fuses of the same type and rating.
WA RNING
Electrical shock hazard. Disconnect the instrument from the
mains supply before replacing fuses.
Table 3
30
AC board fuses
Fuse
designation
Line voltage
Fuse rating and type
F1/F2
All
15 A, 250 VAC, IEC type F (non-time
delay), ceramic body
F6/F5
All
0.75 A, 250 VAC, IEC type F (non-time
delay), glass body
F4/F3
All
10 A, 250 VAC, IEC type F (non-time
delay), glass body
SCD and NCD User Manual
Safety and Regulatory Information
2
Safety and Regulatory Information
This instrument has been designed and tested in accordance
with IEC Publication 61010-1 Safety Requirements for Electrical
equipment for Measurement, Control, & Laboratory Use, and
has been supplied in a safe condition. The instruction
documentation contains information and warnings which must
be followed by the user to ensure safe operation and to maintain
the instrument in a safe condition.
Refer to the 7890B GC Safety Manual, available on the GC and
GC/MS User Manuals & Tools DVD, for general safety and
regulatory information for the 7890B GC. The sections below
provide information specific to the 8355 SCD and 8255 NCD.
The Agilent 8355 SCD and 8255 NCD conform to the following
safety standards:
• Canadian Standards Association (CSA): C22.2 No. 61010-1
• CSA/Nationally Recognized Test Laboratory (NRTL):
ANSI/UL 61010-1
• International Electrotechnical Commission (IEC): 61010–1,
61010-2-010
• EuroNorm (EN): 61010–1
This is a safety Class I, Pollution Degree 2, Installation
Category II product. It must be wired to a mains supply with a
protective earthing ground incorporated into the power cord.
Any interruption of the protective conductor, inside or outside
the equipment, is likely to make the instrument dangerous.
Intentional interruption is prohibited.
If this instrument is used in a manner not specified by Agilent,
the protection provided by the instrument may be impaired.
The Agilent 8355 SCD and 8255 NCD conform to the following
regulations on Electromagnetic Compatibility (EMC) and Radio
Frequency Interference (RFI):
• CISPR 11/EN 55011: Group 1, Class A
• IEC/EN 61326
• AUS/NZ
This ISM device complies with Canadian ICES-001. Cet appareil
ISM est conforme a la norme NMB—001 du Canada.
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2
Safety and Regulatory Information
The Agilent 8355 SCD and 8255 NCD are designed and
manufactured under a quality system registered to ISO 9001.
Declaration of Conformity available.
Instructions for Disposal of Waste Equipment by Users in the
European Union: This symbol on the product or its packaging
indicates that this product must not be disposed of with other
waste. Instead, it is your responsibility to dispose of your waste
equipment by handing it over to a designated collection point
for the recycling of waste electrical and electronic equipment.
The separate collection and recycling of your waste equipment
at the time of disposal will help conserve natural resources and
ensure that it is recycled in a manner that protects human
health and the environment. For more information about where
you can drop off your waste equipment for recycling, please
contact your local city recycling office or the dealer from whom
you originally purchased the product.
Sound Emission Certification for Federal Republic of Germany
Sound pressure Lp < 68 dB(A) operator and Lp < 72 dB(A)
bystander according to DIN-EN 27779 (Type test).
Schalldruckpegel
Schalldruckpegel Lp < 68 dB(A) Operator and Lp < 72 dB(A)
Bystander nach DIN-EN 27779 (Typprufung).
Electromagnetic compatibility
This device complies with the requirements of CISPR 11.
Operation is subject to the following two conditions:
• This device may not cause harmful interference.
• This device must accept any interference received, including
interference that may cause undesired operation.
If this equipment does cause harmful interference to radio or
television reception, which can be determined by turning the
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SCD and NCD User Manual
2
Safety and Regulatory Information
equipment off and on, the user is encouraged to try one or more
of the following measures:
1 Relocate the radio or antenna.
2 Move the device away from the radio or television.
3 Plug the device into a different electrical outlet, so that the
device and the radio or television are on separate electrical
circuits.
4 Make sure that all peripheral devices are also certified.
5 Make sure that appropriate cables are used to connect the
device to peripheral equipment.
6 Consult your equipment dealer, Agilent Technologies, or an
experienced technician for assistance.
7 Changes or modifications not expressly approved by Agilent
Technologies could void the user’s authority to operate the
equipment.
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33
2
Safety and Regulatory Information
Intended Use
Agilent products must only be used in the manner described in
the Agilent product user guides. Any other use may result in
damage to the product or personal injury. Agilent is not
responsible for any damages caused, in whole or in part, by
improper use of the products, unauthorized alterations,
adjustments or modifications to the products, failure to comply
with procedures in Agilent product user guides, or use of the
products in violation of applicable laws, rules or regulations.
Cleaning
To clean the unit, disconnect the power and wipe down with a
damp, lint-free cloth.
Recycling the Product
For recycling, contact your local Agilent sales office.
Technical Assistance
This instrument ships with documentation for operation,
routine maintenance, and troubleshooting. To obtain additional
technical assistance, visit the technical support pages available
on the Agilent web site at http://www.agilent.com, or contact
your local Agilent sales office. For the most up-to-date contact
information, visit the Agilent website at:
http://www.chem.agilent.com/en-US/Contact-US/Pages/Contac
tUs.aspx.
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SCD and NCD User Manual
Agilent 8355 SCD and 8255 NCD
User Manual
3
System Description
Specifications 36
Theory of Operation 37
Description of Major Components
39
This chapter provides typical performance specifications, and
describes the theory of operation for the 8355 SCD and 8255
NCD.
Agilent Technologies
35
3
System Description
Specifications
This section lists the published specifications for a new
detector, installed on a new Agilent 7890B GC, when used in a
typical laboratory environment.
8355 SCD
Specification
Minimum Detection Limit (MDL),
typical
< 0.5 pg (S)/s (2x Agilent data system
ASTM noise)
Linearity
> 104
Selectivity
> 2 x 107 response S/response C2
Precision* and stability
< 2 % RSD over 2 hours
< 5 % RSD over 24 hours
Typical time to reach 800 °C from
ambient
10 min
*
Typically, based on one run per 30 minutes, collected over 24 hours. For example, a 24
hour time span will contain approximately 48 replicate runs.
8255 NCD
Specification
36
Minimum Detection Limit, typical
< 3 pg (N)/s (2x Agilent data system
ASTM noise)
Linearity
> 104
Selectivity
> 2 x 107 response N/response C
Area repeatability
< 1.5 % RSD over 8 hours
< 2 % RSD over 18 hours
Typical time to reach 800 °C from
ambient
10 min
SCD and NCD User Manual
System Description
3
Theory of Operation
The Agilent 8255 and 8355 chemiluminescence detectors detect
target molecules by chemically transforming them in several
steps to an excited species that emits light. The light from this
emission is converted to an electrical signal by a
photomultiplier tube (PMT). For each detector, samples undergo
preliminary reaction(s) with an oxidizer (air for SCD, oxygen
for NCD) and hydrogen in a very hot reaction zone (the burner)
at reduced pressure to form either SO or NO in addition to other
products such as H2O and CO2. The reaction products then flow
to a reaction cell in a separate detector module. In this cell, they
mix with ozone (O3) produced from oxygen using an ozone
generator. The O3 reacts with SO or NO to generate SO2* and
NO2* respectively. This reaction cell operates at a pressure of
about 4-7 Torr. These high energy species return to ground state
by chemiluminescence. The emitted light is filtered and then is
detected by a PMT. The electrical signal produced is
proportional to the amount of SO2* or NO2* formed in the
reaction cell. The sample exits the reaction cell, passes through
an ozone destruction trap, and then passes through a vacuum
pump and out to vent.
SCD
The SCD uses the chemiluminescence (light-producing reaction)
from the reaction of ozone with sulfur monoxide (SO) produced
from combustion of the analyte:
Sulfur compound (analyte)
SO + O3
SO + H2O + other products
SO2 + O2 + hQ (< 300-400 nm)
The pressure differential produced by a vacuum pump transfers
the combustion products into a reaction cell, where excess
ozone is added. Light (h) produced from the subsequent
reaction is optically filtered and detected with a blue-sensitive
photomultiplier tube, and the signal is amplified for display or
output to a data system.
NCD
The NCD uses the chemiluminescence of ozone with nitric oxide
formed from combustion. Reacting nitric oxide with ozone
results in the formation of electronically excited nitrogen
dioxide. The excited nitrogen dioxide emits light, a
chemiluminescence reaction, in the red and infrared region of
SCD and NCD User Manual
37
3
System Description
the spectrum. The light emitted is directly proportionally to the
amount of nitrogen in the sample:
NO + O3
NO2 + O2
NO + O3
NO2 + O2 + hQ(~600 to 3,000 nm)
The light (h) emitted by the chemical reaction is optically
filtered and detected by a PMT. A chiller cools the PMT to
reduce thermal noise and help measure infrared light. The
signal from the PMT is amplified for display or output to a data
system.
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SCD and NCD User Manual
System Description
3
Description of Major Components
Burner assembly
The burner assembly mounts on top of the GC in a detector
location, and contains the column connection.
For the SCD, the burner provides two heated zones, one at the
base and one farther up the assembly. In the burner base region,
the column effluent mixes with the lower hydrogen flow and air
at high temperature. The resulting hydrogen flame combusts the
effluent. Low concentration components burn to form the usual
combustion products, including SO2 for compounds containing
sulfur. The products are drawn upward through a ceramic tube,
where at even higher temperature the upper hydrogen flow
mixes with the combustion products, causing the SO2 to reduce
into SO.
Figure 6 shows the flow paths for the SCD burner assembly.
SCD and NCD User Manual
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3
System Description
To detector
Upper hydrogen
Ceramic tube,
upper
Burner
Ceramic tube,
lower
Oxidizer
Lower hydrogen
Base heater
&ROXPQÁRZ
Figure 6
Column
SCD flows
For the NCD, the burner provides two heated zones, one at the
base and one farther up the assembly. In the burner base region,
the column effluent mixes with hydrogen and air at high
temperature. The resulting hydrogen flame combusts the
effluent. Low concentration components will burn to form the
usual combustion products, including NO2 for compounds
containing nitrogen. The products are drawn upward through a
quartz tube and catalyst, where a high temperature will convert
NO2 into NO.
Figure 7 shows the flow paths for the NCD burner assembly.
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SCD and NCD User Manual
System Description
3
To detector
Quartz tube
Burner
Oxidizer
Hydrogen
Base heater
Column
&ROXPQÁRZ
Figure 7
NCD Flows
Ozone generator
The ozone generator provides ozone that reacts with any SO or
NO in the reaction cell to generate SO2* and NO2* respectively.
These high energy species return to ground state by
chemiluminescence.
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3
System Description
Reaction cell and photomultiplier tube (PMT)
The ozone generator discharges ozone into the reaction cell.
This ozone reacts with any SO or NO to generate SO2* and NO2*
respectively. As the species return to ground state though
chemiluminescence, the photomultiplier tube produces a
current proportional to the intensity of emitted light. A
bandpass filter is used to optimize the detector for either sulfur
or nitrogen detection.
EPC modules
The detector controls hydrogen, oxidizer (air or oxygen), and
ozone supply (oxygen) gas flows using two electronic pressure
control modules.
Vacuum pump
A two-stage, oil-sealed rotary vacuum pump provides an
operating pressure between 3 and 10 Torr in the reaction cell.
This vacuum helps transfer combustion gases from the burner
to the reaction cell, as well as transferring the ozone from the
ozone generator into the reaction cell. The vacuum pump also
reduces non-radiative collisional quenching of the emitting
species in the reaction cell.
Ozone destruction trap
A chemical trap between the detector exhaust and the vacuum
pump destroys ozone, converting it to diatomic oxygen.
Unconverted ozone reduces pump life.
Oil coalescing filter
The oil-sealed rotary vacuum pump uses a partially-open gas
ballast to aid in the elimination of water produced in the burner
and transferred to the pump. As a result of the open gas ballast
and the relatively high flow rates of gases, oil vaporized in the
pump can escape through the pump exhaust. To minimize oil
loss, the pump includes an oil coalescing filter on the pump
exhaust to trap vaporized oil and to return this oil to the
vacuum pump oil reservoir.
FID adapter (optional)
The SCD burner normally mounts onto the GC oven directly as a
stand-alone detector. However, some applications also require
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SCD and NCD User Manual
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System Description
simultaneous detection of hydrocarbon components using a
single column without splitting. For this reason, Agilent offers
an optional FID adapter to mount the burner assembly onto an
FID for the simultaneous collection of FID and SCD
chromatograms. During dedicated SCD operation, 100 % of the
column effluent passes through the burner to the detector.
During simultaneous detection, approximately 10 % of the FID
exhaust gases are drawn into the burner through a restrictor,
which reduces SCD sensitivity to approximately 1/10 of the
signal observed in a dedicated SCD burner.
NCD chiller
For NCD, the detector uses a Peltier cooler to lower the PMT
temperature, which in turn reduces noise. This chiller cools the
PMT relative to the current ambient temperature. Higher
laboratory ambient temperatures may result in higher PMT
temperatures. Fluctuations in ambient temperature may result
in fluctuations in PMT temperature.
Since noise and response determine the MDL, the efficiency of
the chiller can influence the MDL. Depending on the ambient
temperature, the chiller may not be able to maintain a
sufficiently cool temperature in the PMT, and XCD noise will
increase, therefore increasing the MDL.
Because chiller efficiency depends on the ambient temperature
inside the detector and in the laboratory, the chiller setpoint
does not impact detector readiness. A GC run can start
regardless of whether or not the chiller has cooled the GC to
setpoint.
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44
System Description
SCD and NCD User Manual
Agilent 8355 SCD and 8255 NCD
User Manual
4
Operation
Introduction 46
Setting Parameters 47
Detector Stability and Response 51
Typical Operating Conditions 52
Adjusting the Operating Conditions 53
Start-up 54
Resource Conservation 55
Shutdown 56
Configure Auto Flow Zero on the GC 57
Configure the Detector 58
This chapter describes the how to use the 8355 SCD and 8255
NCD. This chapter assumes familiarity with using the data
system, if used, and the GC front panel keyboard and display.
For more information, please see the data system online help
and the instrument documentation available on the Agilent GC
and GC/MS User Manuals and Tools DVDs.
Agilent Technologies
45
4
Operation
Introduction
Integrated version
When installed on an Agilent 7890B or 7890A+ GC, program
and operate the SCD and NCD as you would any other detector
on the GC. For Agilent data system users, use the integrated GC
driver to access the operating parameters. For standalone GC
users, access these parameters from the GC front panel and
keyboard. The settings and information provided by the driver
and GC keyboard include:
• Settings for temperatures, flows, and gas types
• Sequence integration
• Method storage
• Early Maintenance Feedback (EMF) settings, data rate
settings, error logging, maintenance logging, and status
information
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SCD and NCD User Manual
4
Operation
Setting Parameters
This section lists the parameter ranges for the SCD and NCD.
The available setpoints provide a wide range suitable for a large
variety of applications as well as for method development. See
“Adjusting the Operating Conditions” on page 53 for important
details about the relationships between the setpoints.
Parameters and ranges
The table below lists the available parameters for the detector.
Table 4
8355 SCD and 8255 NCD parameters and ranges
Parameter
Range, SCD
Range, FID-SCD
Range, NCD
125 – 400 °C
125 – 400 °C
125 – 400 °C
100 – 1000 °C
100 – 1000 °C
100 – 1000 °C
Chiller temperature (NCD only)
On/Off
On/Off
On/Off
Lower hydrogen flow
5 – 25 mL/min
—
1 – 25 mL/min
Upper hydrogen flow (SCD only)
25 – 100 mL/min
25 – 100 mL/min
—
Oxidizer flow
25 – 150 mL/min
5 – 100 mL/min
4 – 80 mL/min
O3 Generator flow
On/Off
On/Off
On/Off
O3 Generator high voltage
On/Off
On/Off
On/Off
Vacuum pump
On/Off
On/Off
On/Off
Oxidizer gas type
Air
Air
Oxygen
O3 Generator gas type
Oxygen
Oxygen
Oxygen
Ignore Ready
See the GC Operating Manual.
Signal
XCD. See the GC Advanced Operation Manual.
Method
Base temperature
Burner temperature
*
Configuration
*
Chiller (PMT cooler) operation depends on the current detector ambient temperature. The actual chiller
temperature does not impact detector readiness. See “NCD chiller” on page 43.
Note that PMT voltage is fixed at 800 V.
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4
Operation
Software control
When using an Agilent data system, open an online session and
edit the instrument acquisition parameters to change method
settings. Select the detector from the method editor, typically
Detectors > Front Detector (or Back Detector or Aux Detector, as
appropriate for your setup). See Figure 8, Figure 9, and Table 5.
Figure 8
48
Example SCD parameters in a data system
SCD and NCD User Manual
4
Operation
Figure 9
Example NCD parameters in a data system
For tandem configurations, for example a front FID-SCD, the
FID will be the front detector, and the XCD will be an Aux
detector.
To access configuration parameters using data system control,
select Configuration > Modules. See Figure 10 for an example.
Figure 10 Example of SCD and NCD configuration parameters
See “Configure the Detector” on page 58 for more information.
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4
Operation
GC keyboard control
To access the method parameters for an SCD or NCD, press the
[Front Det], [Back Det], or [Aux Det #] (tandem FID-XCD
configuration only) key. See Table 5.
To turn on the PMT voltage, press [Config], then press the key for
the detector ([Front Det], [Back Det], or [Aux Det #]). The PMT
voltage can be turned on or off. The PMT operates at a constant
voltage (800 V).
Identifying the detector
Table 5 lists the expected configurations for an XCD.
Table 5
50
Connections to the GC wiring harnesses
XCD Installation
Which detector is the XCD?
Front XCD
Front
Back XCD
Back
Single front FID-XCD (front tandem
FID-XCD)
Front: Front FID
Aux detector 2: XCD
Single back FID-XCD (back tandem
FID-XCD)
Back: Back FID
Aux detector 2: XCD
Dual front FID-XCD and back FID-XCD
(Dual tandem FID-XCD)
Front: Front FID
Aux detector 1: front XCD
Back: Back FID
Aux detector 2: back XCD
SCD and NCD User Manual
Operation
4
Detector Stability and Response
The time required for system stabilization varies depending on
the application, system cleanliness, the presence of active sites,
and other factors.
• When starting an existing system, typically wait at least
10 minutes before using the system to collect data.
• A new burner or a new set of ceramic tubes may take up to
24 hours to condition. Set the detector to the operating
conditions, and monitor the baseline until the baseline
becomes stable enough for your application.
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Operation
Typical Operating Conditions
Table 6 lists the recommended starting conditions for SCD and
NCD methods. These conditions should provide acceptable
results for a wide variety of applications. However, optimize
these conditions as needed to improve the performance of the
specific application.
Table 6
Typical operating conditions, SCD and NCD
Parameter
SCD
NCD
Base temperature, °C
250
250
Burner temperature, °C
800
900
Chiller temperature
N/A
On
Upper H2 flow, mL/min
40
N/A
Lower H2 flow, mL/min
10
3
Oxidizer flow, mL/min
50, Air
8, Oxygen
O3 Generator flow, mL/min
On
On
O3 Generator high voltage
On
On
Vacuum pump
On
On
Burner pressure, Torr, typical reading
< 425 Torr
< 120 Torr
Reactor pressure, Torr (read only)
Should be below
7 Torr
Should be below
5 Torr
The checkout methods for the SCD and NCD also provide
example parameters for balancing good detection limit, good
selectivity, and reasonable ceramic tube life. In any XCD
method:
• Always keep oxidizer gas flowing through the burner.
• The firmware will not allow hydrogen to flow into the burner
while there is no oxidizer to protect the system.
During startup and shutdown, always turn on the pump first
and turn off the pump last to prevent contamination or damage.
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SCD and NCD User Manual
Operation
4
Adjusting the Operating Conditions
Table 4 on page 47 lists the range of values for each parameter,
as limited by the GC firmware. To provide flexibility during
method development for particular application, the range is
wider than needed for most applications.
However, hydrogen flows in the SCD need particular attention.
Using very high hydrogen flows (both upper and lower), relative
to the oxidizer flow, can permanently damage the ceramic
tubes. This condition may not be recoverable. See “Hydrogen
Poisoning” on page 103.
SCD lower hydrogen flow: Very high flow can damage the
ceramic tubes.
NCD lower hydrogen flow: The NCD can operate without
hydrogen flow, although this is not recommended. The hydrogen
flame/plasma can help burn off solvent and heavy molecules. If
operating an NCD without hydrogen flow, plumb the 1/16-inch
tubing for the lower hydrogen flow to the oxygen supply.
Otherwise, residual hydrogen in the tubing will continue diffuse
into the burner and affect stability.
1 Disconnect the Lower H2 line from the back of the detector
and cap off the detector fitting.
2 Install a 1/16-inch Swagelok Tee fitting in the Oxidizer output
from the detector body.
3 Connect the Oxidizer and Lower H2 lines to the Tee fitting.
You will typically need to adjust the recommended starting
conditions to create an optimized method for your application.
When optimizing SCD or NCD method parameters, consider the
following:
• A higher hydrogen to oxidant ratio may initially show higher
response, but later yield a reduced response because of the
accumulation of contaminants that reduce detector
response, such as soot or other active species.
• Operating the burner at higher temperatures may shorten
the useful lifetimes of the heater, thermocouple, and seal
materials.
In general, when making any parameter change, allow sufficient
time for the system to reach equilibrium. Monitor the baseline
until it stabilizes at its new value.
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Operation
Start-up
How to start the detector depends on whether or not you have
created a method for the detector.
If a valid method exists: After you have used the SCD/NCD (at
least one valid method exists), start the detector by loading the
method. As soon as the method loads, the GC will turn on the
vacuum pump and oxidizer flows, and also turn on all other
parameters except hydrogen flow. The GC will monitor the
temperatures and prevent hydrogen flow until the base
temperature reaches 150 °C and the burner temperature
reaches 200 °C. Once the detector temperatures reach these
minimum limits, the GC turns on the hydrogen flow.
During initial startup, or whenever there are no method
parameters set for the SCD or NCD, start the detector as
follows:
1 Access the method parameters.
• At the GC front panel, press [Front Det], [Back Det], or [Aux
Det #].
• In the data system, select the detector in the method
editor.
2 Turn on the vacuum pump.
3 Set the oxidizer flow rate and turn on the oxidizer flow.
4 Wait 1–2 minutes for the vacuum pump to purge the system
using the oxidizer flow.
5 Set the base temperature and turn it on.
6 Set the burner temperature and turn it on.
7 For NCD only: Set the chiller temperature and turn it on.
8 Set the hydrogen flow and turn it on.
9 Set the ozone supply gas flow and turn it on.
10 Turn on the ozone supply gas high voltage.
The GC will monitor the temperatures and prevent hydrogen
flow until the base temperature reaches 150 °C and the burner
temperature reaches 200 °C. Once the detector temperatures
reach these minimum limits, the GC turns on the hydrogen flow.
If needed, also turn on the PMT voltage. See “Configure the
Detector” on page 58.
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SCD and NCD User Manual
Operation
4
Resource Conservation
To conserve resources during periods of inactivity, for example,
overnight or over a weekend, use the 7890B GC’s resource
conservation features to load a sleep method. (See the GC
Operation Manual for details on using sleep and wake
methods.)
A sleep method for an SCD or NCD should do the following:
• Turn off all hydrogen flows
• Maintain base temperature of 125 °C to prevent
condensation
• Maintain burner temperature of at least 200 °C to prevent
condensation
• Set an oven temperature of 30°C to minimize column bleed
In addition, a sleep method can also:
• Turn on gas saver mode to reduce column flow
• Turn off the ozone generator and ozone supply gas flow
• Turn off the chiller (NCD only)
• Turn off the vacuum pump if carrier gas and the oven are
turned off. (If the carrier gas flow is on, do not turn off the
vacuum pump. With the vacuum pump off, any carrier gas
flow will eventually cause a flow shutdown.)
It is good practice to leave on the oxidizer flow if the vacuum
pump is on.
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4
Operation
Shutdown
When turning off the detector for a long period of time, or to
perform maintenance on the GC or detector, shut down the
detector as follows:
1 Access the method parameters.
• At the GC front panel, press [Front Det] or [Back Det], or
[Aux Det #].
• In the data system, select the detector in the method
editor.
2 Turn off the ozone supply gas high voltage.
3 Turn off the ozone supply gas flow.
4 Turn off the hydrogen flow.
5 For NCD only: Turn off the chiller.
6 Turn off the burner heater.
7 Turn off the base heater.
NOTE
When shutting down, the GC will keep the vacuum pump and oxidizer
flow running until approximately 100 mL of oxidizer gas has purged the
system after the hydrogen flow is turned off. This action prevents
moisture residual contamination.
8 Turn off the oxidizer flow.
9 Turn off the vacuum pump.
10 Turn off the detector power.
11 If shutting down the GC, turn off the GC.
WA RNING
Burn hazard. Many parts of the GC can be dangerously hot. If
performing GC or detector maintenance, turn off all heated zones
and monitor them until they reach a safe handling temperature
before turning off the GC.
Alternately, create a method that turns off all detector
components, and load that method to shut down the detector.
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SCD and NCD User Manual
4
Operation
Configure Auto Flow Zero on the GC
Agilent recommends setting the GC to automatically zero flow
sensors to reduce drift. See the GC Operation Manual for
details.
1 On the GC keypad, press [Options].
2 Scroll to Calibration and press [Enter].
3 Scroll to select the appropriate detector (front, back, aux 2,
or aux 1) and press [Enter].
4 Scroll to Autoflow zero (H2 Lower) and press [On/Yes]. (To turn
off autozero, instead press [Off/No].
5 For SCD, repeat for Autoflow zero (H2 Upper).
SCD and NCD User Manual
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4
Operation
Configure the Detector
For an SCD or NCD, gas types are usually set once. The SCD
uses oxygen for the ozone supply gas and air for the oxidizer
gas, while the NCD uses oxygen for both.
To configure the gas types for an SCD or NCD by using the GC
keyboard:
1 At the GC keyboard, press the keys to access the detector, for
example [Config][Front Det].
2 Scroll to Oxidizer Gas and press [Mode/Type].
3 Scroll to the correct gas type, Air (SCD) or Oxygen (NCD), and
press [Enter].
If using data system control, you can set the gas types through
the data system.
1 From the data system, open the GC parameters user
interface. For example, in Agilent OpenLAB select Home >
Method > Instrument Setup > Configuration > Modules.
2 Select the gas types for the method.
Figure 11 Example of SCD and NCD configuration parameters
3 Click OK and save the method changes.
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SCD and NCD User Manual
Operation
4
The PMT voltage can be turned on or off only at the GC front
panel. To enable or disable the PMT voltage:
1 At the GC keyboard, press the keys to access the detector, for
example, press [Config][Front Det] for an XCD mounted in the
front position, or press [Config][Back Det] for an XCD
mounted in the back position.
2 Scroll to PMT Voltage.
3 Press On/Yes to turn on the voltage, or Off/No to turn it off.
Press [Enter].
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Operation
SCD and NCD User Manual
Agilent 8355 SCD and 8255 NCD
User Manual
5
Maintenance
Maintenance Log and Early Maintenance Feedback (EMF)
Maintenance Schedule 63
Tracking Detector Sensitivity 64
Consumables and Replacement Parts 65
Exploded Parts View of the SCD 67
Exploded Parts View of the NCD 68
Detector Maintenance Method 69
Attach a Column to the Detector 70
Replace the Inner Ceramic Tube (SCD) 73
Replace the Quartz Tube (NCD) 76
Check the Vacuum Pump Oil 80
Add Vacuum Pump Oil 81
Replace the Vacuum Pump Oil 83
Replace the Ozone Trap 85
Change the Oil Mist Filter 87
Clean the Detector Exterior 88
Calibrate the Flow and Pressure Sensors 89
Updating Firmware 90
62
This chapter describes the routine maintenance procedures
needed for normal use of the SCD and NCD.
Agilent Technologies
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5
Maintenance
Maintenance Log and Early Maintenance Feedback (EMF)
When using the detector with an Agilent 7890B GC, use the
Early Maintenance Feedback (EMF) feature to track routine
maintenance. The EMF feature is available at the GC front panel
and in any Agilent data system, and can help you replace the
filters and oil before contamination becomes a problem.
The Agilent 7890B GC provides the following counters for the
SCD, NCD, and vacuum pump:
Component
Part with a counter
Counter type
Detector
Detector
Number of injections
Outer tube (SCD only)
Number of injections
Inner tube (SCD only)
Number of injections
Quartz tube (NCD only)
Number of injections
Gas filters
Time (days)
Pump oil
Time (days)
Oil mist filter
Time (days)
Vacuum pump
Default value
3 months
If not using the GC EMF feature, manually keep a maintenance
log that tracks:
• Dates of maintenance and type of maintenance performed
• Operational changes that might impact performance, such as
changes in temperature settings and hydrogen flows
• Pressures during normal method runs
• Background signal (the difference between ozone “on” and
ozone “off”)
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Maintenance
5
Maintenance Schedule
To maintain optimum performance of the Agilent 8355 SCD and
8255 NCD, routinely replace the ozone trap, oil coalescing filter,
and vacuum pump oil. Refer to Table 7 for the expected life
span of each item.
Table 7
SCD and NCD User Manual
Recommended Edwards RV5 vacuum pump maintenance
schedule
Component
Operating life*
Chemical trap (converts O3 to O2)
~ 6 months
Oil coalescing filter
~ 3 months
Oil odor filter
~ 3 months if needed
Pump oil†
~ 3 months
Oil level
Check weekly
*
The operating life is based on the total time logged during operation of the detector with
the burner and the ozone generator On.
†
Pump oil can be purchased from a supplier or directly from Agilent: SAE 10W-30,
Multiviscosity Synthetic Motor Oil such as, MOBIL 1 or AMSOIL.
63
5
Maintenance
Tracking Detector Sensitivity
In addition to using the EMF features of the GC and detector,
also track detector sensitivity. Sensitivity reflects the
performance characteristics of a given system, and decreased
sensitivity may indicate the need for routine detector
maintenance. Sensitivity is typically reported as:
Sensitivity =
peak area
amount
Calculate a minimum detection limit (MDL) from the following
formula:
MDL =
2 x noise
sensitivity
where the noise is the ASTM noise reported by the Agilent data
system.
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Maintenance
5
Consumables and Replacement Parts
See the Agilent catalog for consumables and supplies for a more
complete listing, or visit the Agilent Web site for the latest
information (http://www.chem.agilent.com/store).
Table 8
Consumables and parts for the SCD and NCD
Description/quantity
Part number
Detector parts
Ceramic tube, inner, small (SCD)
G6602-45005
Quartz tube (NCD)
G6600-80063
Ferrule, 1/4-inch, graphite, straight, 10/pk for SCD
outer ceramic tube and NCD quartz tube
0100-1324
Column installation tool
G3488-81302
Sulfur chemiluminescence test sample
Nitrogen chemiluminescence test sample
Vacuum pump parts
RV5 pump – 230 V – Inland
G6600-64042
Pump tray, RV5 pump
G1946-00034
PM Kit, RV5 oil pump
G6600-67007
Oil mist filter for RV5 pump, for SCD/NCD
G6600-80043
Replacement oil coalescing filter, RV5 pump
G6600-80044
Replacement odor filtration element
G6600-80045
Ozone destruction trap
G6600-85000
Oil return line, RV5 pump
3162-1057
Oil, synthetic, Mobil 1
G6600-85001
NW 20/25 clamping ring (for oil mist filter)
0100-0549
NW 20/25 clamping ring (for exhaust hose)
0100-1398
Tools
SCD and NCD User Manual
Funnel
9301-6461
Wrench, Allen, 5-mm
8710-1838
Screwdriver, flat-bladed
8710-1020
Gloves, chemical resistant, lint-free
9300-1751
65
5
Maintenance
Table 9
Table 10
Filters for the SCD and NCD
Description/quantity
Part number
Gas Clean filter, sulfur (filters sulfur and moisture)
CP17989
Gas Clean Filter SCD Kit, for sulfur
chemiluminescence detectors
CP17990
Nuts, ferrules, and hardware for capillary columns
Column id (mm)
Description
Typical use
Part number/quantity
.53
Ferrule, graphite, 1.0-mm id
0.53-mm capillary columns
5080-8773 (10/pk)
Ferrule, graphite, 0.8-mm id
0.53-mm capillary columns
500-2118 (10/pk)
Column nut, finger-tight (for
0.53-mm columns)
Connect column to inlet or detector
5020-8293
.45
Ferrule, graphite, 0.8-mm id
0.45-mm capillary columns
500-2118 (10/pk)
.32
Ferrule, graphite, 0.5-mm id
0.1-mm, 0.2-mm, 0.25-mm, and
0.32-mm capillary columns
5080-8853 (10/pk)
Column nut, finger-tight
(for .100- to .320-mm columns)
Connect column to inlet or detector
5020-8292
Ferrule, graphite, 0.4-mm id
0.1-mm, 0.2-mm, 0.25-mm, and
0.32-mm capillary columns
500-2114 (10/pk)
Column nut, finger-tight (for
.100- to .320-mm columns)
Connect column to inlet or detector
5020-8292
Ferrule, no-hole
Testing
5181-3308 (10/pk)
Capillary column blanking nut
Testing–use with any ferrule
5020-8294
Column nut, universal
Connect column to inlet or detector
5181-8830 (2/pk)
Column cutter, ceramic wafer
Cutting capillary columns
5181-8836 (4/pk)
Ferrule tool kit
Ferrule installation
440-1000
.1 – .25
All
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Maintenance
5
Exploded Parts View of the SCD
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Figure 12
SCD Exploded parts view
SCD and NCD User Manual
67
5
Maintenance
Exploded Parts View of the NCD
Coupling
1/4-inch graphite ferrule, straight
Quartz tube
Shroud assembly
Burner heater
Burner lower nut
1/4-inch graphite ferrule, straight
Jet assembly and coupling
Detector base
Insulation, top
Insulation, bottom
Insulation cup
Ferrule
Column nut
Column installation tool
Figure 13
68
NCD exploded parts view
SCD and NCD User Manual
5
Maintenance
Detector Maintenance Method
It is good practice to create a maintenance method for the GC
that prepares the GC and detector for maintenance. Load this
method before performing maintenance.
A maintenance method for the SCD should do the following:
1 Turn off the heater and burner to allow them to cool.
2 Turn off all hydrogen flows.
3 Leave on the oxidizer and ozone supply gases.
4 Turn off the ozone generator.
5 Leave on the vacuum pump.
6 Keep (helium) carrier gas flowing.
7 Set the oven to 30 °C to minimize column bleed.
8 Cool any other parts of the GC (oven, inlet, and so forth) as
needed.
A maintenance method for the NCD should do the following:
1 Turn off the heater and burner to allow them to cool.
2 Turn off the hydrogen flow.
3 Leave on the oxidizer and ozone supply gases.
4 Turn off the ozone generator.
5 Leave on the vacuum pump.
6 Keep (helium) carrier gas flowing.
7 Set the oven to 30 °C to minimize column bleed.
8 Cool any other parts of the GC (oven, inlet, and so forth) as
needed.
Allow heated zones to cool to < 40 °C for safe handling.
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Maintenance
Attach a Column to the Detector
NOTE
This procedure describes how to attach a column directly to an XCD. In a
tandem FID-XCD installation, install the column into the FID as described
in the FID instructions. See the GC documentation.
1 Gather the following materials (see “Consumables and parts
for the SCD and NCD” on page 65):
• Column installation tool for SCD/NCD (G3488-81302)
• Column
• Ferrule (for column)
• Column nut
• Column cutter
• 1/4-inch open-end wrench
• Septum
• Isopropanol
• Lab tissue
• Lint-free gloves
• Magnifying loupe
70
WA RNING
The oven, inlet, or detector may be hot enough to cause burns. If
the oven, inlet, or detector is hot, wear heat-resistant gloves to
protect your hands.
WA RNING
Wear safety glasses to protect your eyes from flying particles
while handling, cutting, or installing glass or fused silica
capillary columns. Use care in handling these columns to prevent
puncture wounds.
CAUTION
Wear clean, lint-free gloves to prevent contamination of parts with
dirt and skin oils.
SCD and NCD User Manual
5
Maintenance
2 Prepare the detector for maintenance.
a Load the GC maintenance method and wait for the GC to
become ready. (See “Detector Maintenance Method” on
page 69.) Wait until the inlets, oven, detectors, valve box,
burner assembly, and detector base cool to a safe handling
temperature (< 40 °C).
b Turn off all hydrogen flows. (Leave on the oxidizer and
ozone supply gases.)
c Turn off the ozone generator.
WA RNING
Hydrogen gas is flammable. Turn off all detector (and column)
hydrogen gas flows before performing maintenance on the
detector.
3 Place a septum, capillary column nut, and ferrule on the
column.
Ferrule
Column nut
Column
Septum
Figure 14
Place septum, column nut, and ferrule on the column
4 Insert the end of the column through the column measuring
tool so that the end protrudes beyond the tool.
Score column here
Column measuring tool
Column nut
78 ± 1 mm
Ferrule
Figure 15
Set column length and swage ferrule using column measuring tool
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Maintenance
5 Tighten the column nut into the column measuring tool until
the column nut grips the column. Tighten the nut an
additional 1/8- to 1/4-turn with a pair of wrenches. Snug the
septum against the base of the column nut.
6 Use a column cutting wafer at 45° to score the column.
7 Snap off the column end. The column may protrude about
1 mm beyond the end of the tool. Inspect the end with a
magnifying loupe to make certain that there are no burrs or
jagged edges.
Bad
Good
8 Remove the column, nut, and swaged ferrule from the tool.
9 Wipe the column walls with a tissue dampened with
isopropanol to remove fingerprints and dust.
10 Carefully thread the swaged column into the detector fitting.
Finger-tighten the column nut, then use a wrench to tighten
an additional 1/8 turn.
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Maintenance
Replace the Inner Ceramic Tube (SCD)
To replace the inner ceramic tube:
WA RNING
The oven, inlets, and detectors can be hot enough to cause burns.
Cool these areas to a safe handling temperature before beginning.
CAUTION
Wear clean, lint-free gloves to prevent contamination of parts with
dirt and skin oils.
CAUTION
Most steps in this procedure require the use of two wrenches, one
to hold the burner steady and the other to loosen a part. Always use
two wrenches to avoid over-torquing or bending the burner
assembly.
1 Gather the following:
• Two 7/16-inch open-end wrenches
• 3/8-inch open-end wrench
• New O-ring
• New ceramic tube
• Tweezers
• 1/8-inch cap for transfer line
• T20 Torx driver
2 Prepare the detector for maintenance.
a Load the GC maintenance method and wait for the GC to
become ready. (See “Detector Maintenance Method” on
page 69.) Wait until the inlets, oven, detectors, valve box,
burner assembly, and detector base cool to a safe handling
temperature (< 40 °C).
b Turn off all hydrogen flows. (Leave on the oxidizer and
ozone supply gases.)
c Turn off the ozone generator.
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Maintenance
WA RNING
Hydrogen gas is flammable. Turn off all detector (and column)
hydrogen gas flows before performing maintenance on the
detector.
3 Disconnect the transfer line and quickly cover the open end
with the 1/8-inch cap. Use a 3/8-inch wrench on the transfer
line and a 7/16-inch wrench on the upper fitting to hold the
burner assembly steady.
4 Using two 7/16-inch wrenches, remove the outlet fitting from
the upper fitting.
5 If the old O-ring is stuck to the bottom of the outlet fitting,
use tweezers or similar to gently pry it loose from the fitting.
6 Remove the old inner ceramic tube.
7 Place a new O-ring over the end of the new inner ceramic
tube, and slide the O-ring about 7 mm down the tube. (This
dimension is not critical.)
Inner ceramic tube
O-Ring
~ 7 mm
8 Gently insert the tube and O-ring assembly into the burner
until it rests on the O-ring.
9 Orient the outlet fitting so the hex flats are closer to the
upper fitting, as shown, and install over the ceramic tube.
Tightening the outlet fitting will automatically adjust the
O-ring and ceramic tube positions. Tighten until snug
(finger-tight). Do not overtighten.
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5
10 Reinstall the transfer line onto the outlet fitting. Tighten
until snug (finger-tight). Do not overtighten.
11 Restore the detector gas flows.
12 Check for leaks at the upper hydrogen fitting. Correct a leak
as needed.
13 Restore the remaining detector operating conditions.
14 Reset the EMF counter.
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5
Maintenance
Replace the Quartz Tube (NCD)
To replace the NCD quartz tube:
WA RNING
The oven, inlets, and detectors can be hot enough to cause burns.
Cool these areas to a safe handling temperature before beginning.
CAUTION
Wear clean, lint-free gloves to prevent contamination of parts with
dirt and skin oils.
CAUTION
Most steps in this procedure require the use of two wrenches, one
to hold the burner steady and the other to loosen a part. Always use
two wrenches to avoid over-torquing or bending the burner
assembly.
1 Gather the following:
• Two 7/16-inch open-end wrenches
• 3/8-inch open-end wrench
• 5/8-inch open-end wrench
• New quartz tube
• Tweezers
• 1/8-inch cap for transfer line
• T20 Torx driver
• Dental tool or similar tool for graphite ferrule removal
• 2 New graphite ferrules
2 Prepare the detector for maintenance.
a Load the GC maintenance method and wait for the GC to
become ready. (See “Detector Maintenance Method” on
page 69.) Wait until the inlets, oven, detectors, valve box,
burner assembly, and detector base cool to a safe handling
temperature (< 40 °C).
b Turn off all hydrogen flows. (Leave on the oxidizer and
ozone supply gases.)
c Turn off the ozone generator.
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Maintenance
WA RNING
Hydrogen gas is flammable. Turn off all detector (and column)
hydrogen gas flows before performing maintenance on the
detector.
3 Remove the protective shroud. Remove the two T20 Torx
screws, twist the shroud counter-clockwise to remove it from
the mounting posts, then lift. Set the shroud and screws
aside for later use.
4 Disconnect the transfer line and quickly cover the open end
with the 1/8-inch cap. Use a 3/8-inch wrench on the transfer
line and a 7/16-inch wrench of the upper fitting to hold the
burner assembly steady.
5 Using two 7/16-inch wrenches, remove the outlet fitting from
the nut on the top of the quartz tube.
6 Gently slide the nut and its ferrule up and off of the quartz
tube.
CAUTION
The quartz tube is fragile and can be chipped or cracked. To avoid
damaging the quartz tubes, handle carefully.
7 Using 5/8-inch and 9/16-inch wrenches, remove the burner
assembly and tube from the coupling in the detector base
assembly.
8 Inspect the area around the jet in the coupling. If there are
broken bits of tube present, remove with tweezers or similar
tool.
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Maintenance
9 Gently pull the quartz tube up through the burner assembly
to remove. The graphite ferrule should remain in the rotating
nut in the burner base.
10 Use a dental tool or similar to remove the old graphite
ferrule from the rotating nut in the burner base.
11 Use two wrenches to disassemble the reducer, then remove
the old ferrule.
12 Install new graphite ferrules. In both cases, the tapered end
of the ferrule faces out, away from the burner.
Reducer, top
Ferrule
Rotating lower nut
Ferrule
Reducer, bottom
Quartz tube
13 Reassemble the reducer. Tighten with two wrenches until
snug.
14 Slide the new quartz tube down through the burner assembly
until it protrudes from the base about 1 cm. (This dimension
is not critical. The tube position will adjust as you tighten the
lower nut onto the coupling.)
CAUTION
When tightening the graphite ferrules onto a quartz tube, tighten
only until snug. Overtightening can damage the ferrules or quartz
tubes.
15 Carefully lower the burner assembly onto the detector base
and thread the nut onto the detector base assembly by hand.
Tighten finger-tight, then snug in place using a wrench. Do
not overtighten.
16 Place the nut and ferrule over the open end of the quartz
tube so that the open end of the nut faces up.
17 Install the nut into the outlet fitting and tighten with two
wrenches just until snug.
18 Reinstall the transfer line onto the outlet fitting. Tighten
until snug (finger-tight). Do not overtighten.
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SCD and NCD User Manual
Maintenance
5
19 Reinstall the protective shroud.
20 Restore the detector operating conditions.
21 Reset the EMF counter.
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Maintenance
Check the Vacuum Pump Oil
CAUTION
Never add or replace the foreline pump oil while the pump is on.
Check the level and color of the pump oil weekly.
1 Check the oil level in the window of the foreline pump. The
oil level should be between the marks for Max and Min.
Max
Oil level
Min
Figure 16 Checking the oil level
2 Check that the color of the pump oil is clear or almost clear
with few suspended particles. If the pump oil is dark or full
of suspended particles, replace it.
3 Record the maintenance in the maintenance logbook. If
applicable, reset the EMF counter.
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5
Maintenance
Add Vacuum Pump Oil
Add pump oil when the pump oil level is low.
Materials needed
• Funnel (9301-6461)
• 5-mm Allen wrench (8710-1838)
• Gloves, chemical resistant, clean, lint free (9300-1751)
• Oil, synthetic, Mobile 1 (G6600-85001)
• Safety glasses (goggles)
WA RNING
Never add pump oil while the pump is on.
WA RNING
The fill cap and pump may be dangerously hot. Check that the fill
cup and pump are cool before you touch them.
CAUTION
Use only synthetic 10W30 oil, such as Mobil 1. Any other oil can
substantially reduce pump life and invalidates the pump warranty.
Procedure
1 Shut down the detector and wait for the pump to turn off.
See “Shutdown” on page 56.
2 Turn off the detector and unplug the pump power cord at the
pump.
SCD and NCD User Manual
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5
Maintenance
3 Remove the fill cap on the vacuum pump.
Fill cap
Power cord
receptacle
9ROWDJHFRQÀJXUDWLRQ
SOXJ
4 Add new pump oil until the oil level is near, but not over the
maximum mark beside the oil level window. See Figure 16 on
page 80.
5 Reinstall the fill cap.
6 Wipe off all excess oil around and underneath the pump.
7 Reconnect the pump power cord.
8 Turn on the detector and restore operating conditions. See
“Start-up” on page 54.
9 Record the maintenance in the maintenance logbook. If
applicable, reset the EMF counter.
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SCD and NCD User Manual
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Maintenance
Replace the Vacuum Pump Oil
Replace the pump oil every three months or sooner if the oil
appears dark or cloudy.
Materials needed
• Container for catching used pump oil
• Funnel (9301-6461), 5-mm Allen wrench (8710-1838)
• Gloves, chemical resistant, clean, lint free (9300-1751)
• Oil, synthetic, Mobile 1 (G6600-85001)
• Safety glasses (goggles)
• Screwdriver, flat-bladed, large (8710-1029)
WA RNING
Never add pump oil while the pump is on.
WA RNING
The fill cap and pump may be dangerously hot. Check that the fill
cup and pump are cool before you touch them.
WA RNING
Do not touch the oil. The residues from some samples are toxic.
Properly dispose of the oil.
CAUTION
Use only synthetic 10W30 oil, such as Mobil 1. Any other oil can
substantially reduce pump life and invalidates the pump warranty.
Procedure
1 Shut down the detector and wait for the pump to turn off.
See “Shutdown” on page 56.
2 Turn off the detector and unplug the pump power cord at the
pump.
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Maintenance
3 Place a container under the drain plug of the vacuum pump.
Fill cap
Drain plug
4 Remove the fill cap, then open the drain plug. Drain the oil
completely by raising the motor end of the pump.
5 Reinstall the drain plug.
6 Add new pump oil until the oil level is near, but not over the
maximum mark beside the oil level window. See Figure 16 on
page 80.
7 Reinstall the fill cap.
8 Wipe off all excess oil around and underneath the pump.
9 Reconnect the pump power cord.
10 Turn on the detector and restore operating conditions. See
“Start-up” on page 54.
11 Record the maintenance in the maintenance logbook. If
applicable, reset the EMF counter.
12 Check the pump for leaks after about 30 minutes, and check
again after 24 hours.
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5
Maintenance
Replace the Ozone Trap
To replace the ozone trap:
1 Load a method to cool the detector, turn off the heaters, and
turn off the hydrogen flow.
• Turn off the heaters and allow the burner to cool.
• Leave the oxidizer flow on.
• Turn off the hydrogen flow.
• Turn off the vacuum pump.
• Set the GC oven to 30 °C (or off) to minimize column
bleed.
• Leave (helium) carrier gas flowing.
2 Allow the vacuum pump to cool to a safe handling
temperature.
3 Remove the trap assembly and vacuum hose from the
support bracket.
4 Loosen the two hose clamps that secure the old ozone trap in
place.
Hose clamp
Ozone trap
Hose clamp
5 Remove the trap from the pump intake hose. (If needed,
loosen the clamp at the pump intake.)
6 Lift the old trap from the support bracket, then remove the
detector vacuum hose from the barbed fitting on the old trap.
7 Install the new trap. Make sure that the flow direction arrow
on the new trap points towards the intake fitting. (The trap
SCD and NCD User Manual
85
5
Maintenance
elbow must be nearest the pump intake.) If you removed the
short connector hose from the pump intake, reinstall it.
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Maintenance
5
Change the Oil Mist Filter
The oil mist filter on the RV5 pump has two components: the
charcoal odor filter and the oil coalescing filter element. To
replace the filters, disassemble the oil mist filter assembly with
the 4 mm long-handled hex wrench (provided). The smaller
charcoal odor filter sits on top of the larger oil coalescing filter
element. While it is recommended to replace the oil coalescing
filter element after 90 days of continuous use, replacement of
the charcoal odor filter is optional. After replacing the filter,
re-assemble the filter assembly and attach it to the pump flange.
Reset the EMF counter.
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Maintenance
Clean the Detector Exterior
WA RNING
Burn hazard. The burner assembly can be hot enough to cause
burns. Before touching, cool to a safe handling temperature
(< 40 °C).
WA RNING
Shock hazard. Before cleaning the detector, turn it off and unplug
its power cord.
Before cleaning the detector, shut it down, turn it off, and
unplug the detector power cord. Clean the detector with a damp
cloth using water. Do not spray liquids directly onto the
detector. Wipe dry with a clean, soft cloth. Do not allow cleaning
fluids to drip into the detector or GC because liquids can
damage the detector or GC electronics.
Do not use cleaning agents on the burner assembly that could
cause a hazard on the burner.
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Maintenance
Calibrate the Flow and Pressure Sensors
The 8355 SCD and 8255 NCD use electronic pressure control
modules. Typically, set the 7890B GC to use automatic flow
zeroing. Calibration is generally not required. However, if
needed the flow and pressure sensors can be manually zeroed.
See the GC Operation Manual for details.
SCD and NCD User Manual
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Maintenance
Updating Firmware
The GC firmware controls the detector. Any updates for the
detector will be applied through the GC firmware. See the GC
Firmware Update Tool on the Agilent GC and GC/MS User
Manuals & Tools DVDs, or download the tool from the Agilent
web site GC support pages.
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Agilent 8355 SCD and 8255 NCD
User Manual
6
Troubleshooting
Solving Detector Problems 92
Troubleshooting Table 93
Status Indicator LED 96
Detector Messages 97
Leaks 98
Power Problems 100
Ozone Generation Problems 101
Coking 102
Hydrogen Poisoning 103
Contaminated Gases 104
This chapter describes how to troubleshoot and resolve typical
issues encountered while using an Agilent SCD or NCD.
Agilent Technologies
91
6
Troubleshooting
Solving Detector Problems
A basic understanding of the detector helps to diagnose and
solve detector problems. Review the basic detector theory found
in “Theory of Operation” on page 37. Also, please note that this
section is intended to troubleshoot problems in a detector that
has previously been performing acceptably. If trying to optimize
a new detector application, see “Adjusting the Operating
Conditions” on page 53 for recommendations on adjusting
method setpoints to obtain better results.
Many symptoms may be caused by more than one problem or by
poor chromatographic technique. Analysis of sulfur or nitrogen
compounds has traditionally been very difficult because of the
inherent reactivity and instability of the compounds
themselves. Often, problems initially blamed on the detector
actually originate from either poor chromatographic technique
or other system failures (for example, a leak at the column inlet
fitting). Therefore, the first step in troubleshooting is to isolate
the problem to the GC (inlet, injector, or column), to the burner
assembly, or to the detector (ozone generator, vacuum pump,
photomultiplier tube, or electronics). When diagnosing a
problem in a system that had been working, a good first step is
to restore the default typical operating conditions. The response
under these conditions can help determine whether or not the
method settings are causing the problem.
As a good practice, use the GC’s maintenance log and Early
Maintenance Feedback (EMF) features for the detector. This
feature helps you maintain the detector in good working order
before problems can arise. See the GC Operation Manual for
more information.
Also keep a maintenance log to track detector pressure readings
and background signal (the difference between ozone “on” and
ozone “off”). Changes over time in these values may indicate
maintenance due.
Table 11 in the next section lists many common problems, their
most probable causes, and corrective action that should be
taken.
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6
Troubleshooting Table
Table 11
Troubleshooting Detector Issues
Problem
Possible cause
Diagnosis
Corrective action
No response
No ozone
Little or no difference in
See “No ozone”.
output signal between ozone
On and Off.
No ozone
High voltage transformer
and/or ozone generator
inoperative.
No difference in output
signal between ozone On
and Off even though flow
through the ozone generator
is normal.
Detector problems
Contact Agilent for service.
Restriction in ozone supply
to the reactor cell.
Contact Agilent for service.
No Response
Broken ceramic or quartz
tube.
Replace the ceramic tube.
See “Replace the Inner
Ceramic Tube (SCD)” on
page 73 or “Replace the
Quartz Tube (NCD)” on
page 76.
Low Response
Inappropriate hydrogen and
oxidizer flow rates.
Check flow rates.
Leak in the detector.
Wandering Baseline
Check for leaks in the
detector and repair any
leaks. See “Leaks” on
page 98.
Replace the ceramic tube.
See “Replace the Inner
Ceramic Tube (SCD)” on
page 73 or “Replace the
Quartz Tube (NCD)” on
page 76.
Contaminated ceramic or
quartz tubes.
If there does not appear to
be a leak, then inspect the
ceramic tube. Contamination
can result from column
bleed, samples which
contain volatile metal
complexes, and large
injections of coke-forming
hydrocarbons.
Contamination in one of the
detector gases.
Check the difference in the
Check inline supply traps
output signal between ozone and replace.
On and Off.
Change detector gases.
Leak in the oxidizer lines.
SCD and NCD User Manual
Adjust flow rates.
Check for leaks in the
detector and repair any
leaks. See “Leaks” on
page 98.
93
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Troubleshooting
Table 11
Troubleshooting Detector Issues
Problem
Possible cause
Diagnosis
Leak in the hydrogen supply
lines.
Corrective action
Check for leaks in the
detector and repair any
leaks. See “Leaks” on
page 98.
Tailing peaks with
non-equimolar response
Severe contamination of
detector gases.
High background signal
Check inline supply traps
compared against ozone Off. and replace.
Change detector gases.
Tailing peaks
Poor column connection.
Verify column position at
inlet and outlet. Look for
discoloration of column at
detector fitting which
indicates column in
combustion zone.
Reinstall column. See
“Attach a Column to the
Detector” on page 70.
Cracked tubes.
Confirm pressure and
vacuum ranges. Inspect
columns and ferrules.
Replace the ceramic tube.
See “Replace the Inner
Ceramic Tube (SCD)” on
page 73 or “Replace the
Quartz Tube (NCD)” on
page 76.
Detector thermal shutdown
Thermocouple open.
Contact Agilent for service.
Burner pressure excessively
high.
Cracked quartz or outer
ceramic tube.
Leaking or disconnected
1/16-inch stainless steel
hydrogen or oxidizer line.
Replace the ceramic tube.
See “Replace the Inner
Ceramic Tube (SCD)” on
page 73 or “Replace the
Quartz Tube (NCD)” on
page 76.
Check connection. Check
line for leaks. Contact
Agilent for service if the line
is cracked.
Leak in burner.
Check for leaks in the
detector and repair any
leaks. See “Leaks” on
page 98.
Cracked inner ceramic tube.
See “Replace the Inner
Ceramic Tube (SCD)” on
page 73.
Burner pressure lower than
expected and poor response
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Troubleshooting
Table 12
Troubleshooting Pump Issues
Problem
Possible Cause
Diagnosis
Corrective Action
Vacuum pump problems
Pump does not start
Pump switch off or power
cord disconnected.
Turn On pump power switch.
Check pump power cord.
Fuses blow on startup
Emulsified oil.
Inspect oil for integrity.
Change pump oil, and plug
unit into wall to run for
10–15 minutes.
Contact Agilent to replace
blown fuses.
Water in pump
Cracked coalescing filter.
Milky yellow oil in the pump
window.
Change coalescing filter and
pump oil.
Reaction cell pressure high
Ozone destruction trap
clogged.
Remove ozone destruction
trap from the vacuum line
and re-check expected
pressure readings.
Change chemical trap.
Burner disconnected from
reaction cell.
Check connections.
Vacuum pump defective.
Replace vacuum pump.
Pump loses oil gurgle sound Ballast open.
Oil level drops.
Reset ballast. See
pump-specific sections.
High level of oil in
coalescing filter
No visible movement of oil
in the return line.
Change filter and clear
restrictor.
SCD and NCD User Manual
Plugged oil return restrictor.
95
6
Troubleshooting
Status Indicator LED
Use the detector status LED to quickly determine the status and
readiness of the detector. The LED changes color depending on
the current state of the detector.
• Green: Indicates that power is available for the heaters,
chiller (NCD), vacuum pump, and ozone generator. Note that
the GC supplies power to the detector electronics
independently of the power controlled by the switch on the
front of the detector.
• Yellow: Indicates that the detector is not ready for operation.
Power is on and available, but not all parameters have
reached operating setpoints. A warning or other message
may exist. Check the GC display.
• Red: Indicates a fault or other serious condition. A fault or
other message may exist. Check the GC display. The detector
cannot be used until the fault condition is resolved.
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6
Detector Messages
Check the GC status display for detector messages. The GC will
display and status and error messages that occur during
operation, as well as log detector maintenance and error
messages in the GC log files. See the GC operating manuals for
details.
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6
Troubleshooting
Leaks
Ozone leaks
WA RNING
Ozone is a hazardous gas and a strong oxidant. Exposure to ozone
should be minimized by using the instrument in a well-ventilated
area and by venting the exhaust of the vacuum pump to a fume
hood. The ozone generator should be turned off when the
instrument is not in use.
If you suspect an ozone leak, shut down the detector. Do not
open the detector mainframe. Contact Agilent for service.
Hydrogen leaks
WA RNING
Do not measure hydrogen together with air or oxygen. This can
create explosive mixtures that may be ignited by the high burner
temperature. To avoid this hazard: 1. Cool the burner before you
begin. 2. Always measure gases separately.
Check all external connections for leaks. See “Checking for
hydrogen and oxidizer leaks” on page 99. Check the supply
connections to the detector mainframe and between the
detector mainframe and the burner assembly. If you suspect a
leak inside the detector mainframe, contact Agilent for service.
Do not open the detector mainframe.
Oxidizer leaks
WA RNING
Oxygen rich environments can promote combustion and even
result in spontaneous combustion under conditions of high
pressure and exposure to contamination. Use only oxygen rated
components and ensure that components are oxygen clean prior
to use with pure oxygen.
Check the oxidizer supply connections to the detector
mainframe and between the detector mainframe and the burner
assembly. See “Checking for hydrogen and oxidizer leaks” on
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Troubleshooting
page 99. If you suspect a leak inside the detector mainframe,
contact Agilent for service. Do not open the detector
mainframe.
Checking for hydrogen and oxidizer leaks
To check for a leak in the hydrogen or oxidizer flow paths, do
the following:
1 Check all external fittings for leaks. Correct any leaks
(tighten or remake connections as appropriate).
2 If you still suspect a leak, establish the typical flow checkout
conditions (see Table 14 on page 110 for SCD or Table 15 on
page 115 for NCD).
3 Maintain these conditions for several minutes. If the detector
cannot maintain these flow rates, contact Agilent for service.
4 If the detector was able to maintain the flow rates, turn off
all gas flows using the GC keyboard or the control software.
5 Monitor the pressure readings on the GC display. (Press
[Front Det] or [Back Det] or [MS/Aux Det].) With the vacuum
pump running, the reaction cell pressure should fall to
approximately 0 (zero). The burner pressure should fall to a
value considerably lower than the typical operating pressure.
This process will take time due to the internal configuration
of the burner assembly. If the burner pressure remains high
or at normal pressures, contact Agilent for service.
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6
Troubleshooting
Power Problems
When troubleshooting power problems on an SCD or NCD,
remember that the power supplied to the detector electronics
and flow modules comes from the GC and is controlled by the
GC power switch. The power supplied to the SCD/NCD heaters,
NCD chiller, vacuum pump, and ozone generator comes from
the detector mainframe and is controlled by the detector power
switch.
No power
If the detector does not appear to have power—if the vacuum
pump does not run and the heaters will not turn on—check the
following:
• Check that the power switch is on.
• Check that the power cord is properly connected.
• Check the building power supply.
If the cord if connected properly, and the building circuit for the
detector is operating normally, contact Agilent.
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Troubleshooting
Ozone Generation Problems
Before troubleshooting the ozone generator, first verify that the
other components of the system operate normally. For example,
check for leaks in the detector external connections, check for
leaks in the inlet and inlet column fitting, check that the
vacuum pump operates normally, check that the inlet and ALS
are operating normally, and so on.
Troubleshoot ozone generation as follows:
1 On the GC display, note the detector output signal.
2 Leave the vacuum pump on and ozone supply gas flowing.
3 Turn off the ozone generator.
4 Observe the detector output signal.
5 Turn on the ozone generator and check the detector output
signal again.
A properly operating detector will typically display a difference
in background signal between ozone supply gas voltage on and
off. If no change is observed, contact Agilent service.
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6
Troubleshooting
Coking
Contamination from some sample matrices can reduce
sensitivity. For example, crude oils containing volatile metal
complexes may contaminate the ceramic tubes. In addition,
incomplete combustion of certain hydrocarbon-containing
compounds leaves behind coke deposits on the ceramic tubes.
Coke deposits may be removed from the burner by reducing the
hydrogen flow rate.
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Troubleshooting
Hydrogen Poisoning
Hydrogen poisoning of the SCD ceramic tubes can occur when
the relative oxidizer flow is very much lower than the hydrogen
flow. Whether this state occurs due to inappropriate method
setpoints or due to a problem with the oxidizer flow, this
condition results in extremely reduced or no response. If you
suspect hydrogen poisoning:
• Check for and resolve any flow shutdown.
• Check for restrictions in the oxidizer supply line to the
burner assembly.
• Load the checkout method or other method that uses more
balanced relative flow rates.
If the response does not recover, replace the inner ceramic tube.
If response still does not recover, replace the outer ceramic
tube. The ceramic tubes cannot be reconditioned.
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6
Troubleshooting
Contaminated Gases
Agilent recommends the use of clean gases that meet the
requirements in the Site Preparation Guide. In addition,
Agilent highly recommends the use of high quality traps to
eliminate as much possible contamination as possible. The use
of clean gases is essential for optimal performance. Otherwise,
sulfur and other contaminants from gases may accumulate in
the column and bleed out over time, desensitizing the ceramic
tubes and causing elevated baselines.
Moisture in the ozone generator supply line can lead to the
formation of acids that can damage or destroy the ozone
generator and other detector components. Agilent highly
recommends the use of a high-quality moisture trap, such as the
Gas Clean Filter System with a moisture trap, for the ozone
supply gas. See “Consumables and Replacement Parts” on
page 65.
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Agilent 8355 SCD and 8255 NCD
User Manual
7
Performance Verification
About Chromatographic Checkout 106
Prepare for Chromatographic Checkout 107
Check SCD Performance 109
Check NCD Performance 114
This chapter describes how to verify that the detector is
operating normally.
Agilent Technologies
105
7
Performance Verification
About Chromatographic Checkout
The tests described in this section provide basic confirmation
that the GC and detector can perform comparably to factory
condition. However, as detectors and the other parts of the GC
age, detector performance can change. The results presented
here represent typical outputs for typical operating conditions
and are not specifications.
The tests assume the following:
• Use of an automatic liquid sampler. If not available, use a
suitable manual syringe instead of the syringe listed.
• Use of a 10-μL syringe in most cases. However, a 5-μL syringe
is an acceptable substitute.
• Use of the septa and other hardware (liners, adapters, and so
forth) described. If you substitute other hardware,
performance can vary.
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Performance Verification
Prepare for Chromatographic Checkout
Because of the differences in chromatographic performance
associated with different consumables, Agilent strongly
recommends using the parts listed here for all checkout tests.
Agilent also recommends installing new consumable parts
whenever the quality of the installed ones is not known. For
example, installing a new liner and septum ensures that they
will not contribute any contamination to the results.
When the GC is delivered from the factory, these consumable
parts are new and do not need replacement.
NOTE
For a new GC, check the installed inlet liner. The liner shipped in the inlet
may not be the liner recommended for checkout.
1 Check the indicators/dates on the gas supply traps. Replace
expended traps.
2 Install new consumable parts for the inlet and prepare the
correct injector syringe (and needle, as needed).
Table 13
Recommended parts for checkout by inlet type
Recommended part for checkout
Part number
Split splitless inlet
Syringe, 10-µL
5181-1267
Liner O-ring
5188-5365
Septum
5183-4757
Liner
5190-2295
Gold plated inlet seal, with washer
5188-5367
Multimode inlet
Syringe, 10-µL
5181-1267
Liner O-ring
5188-5365
Septum
5183-4757
Liner
5190-2295
Cool On-column inlet
SCD and NCD User Manual
Septum
5183-4758
Septum nut
19245-80521
107
7
Performance Verification
Table 13
Recommended parts for checkout by inlet type (continued)
Recommended part for checkout
Part number
Syringe, 5-µL on-column
5182-0836
0.32-mm needle for 5-µL syringe
5182-0831
7693A ALS: Needle support insert, COC
G4513-40529
7683B ALS: Needle support assembly for
0.25/0.32 mm injections
G2913-60977
Insert, fused silica, 0.32-mm id
19245-20525
Prepare sample vials
Performance verification requires a 1 uL injection. The
checkout standards for SCD and NCD come with 3 ampuoles.
WA RNING
When handling checkout standards, always follow the handling
precautions recommended with its packaging.
1 Open the sample box.
2 Snap the top off of one checkout sample ampoule.
3 Transfer the contents to a 2-mL ALS sample vial and cap the
vial.
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Performance Verification
Check SCD Performance
1 Gather the following:
• Evaluation column, DB-1 30 m × 0.32 mm × 1.0 μm (part
number 123-1033)
• SCD performance evaluation (checkout) sample
(5190-7003): 0.7 ± 0.002 mg/L diethyl disulfide and
1.0 ± 0.003 mg/L tert-butyldisulfide in isooctane.
• Chromatographic-grade isooctane
• 4-mL solvent and waste bottles or equivalent for
autoinjector
• 2-mL sample vials or equivalent for sample
• Inlet and injector hardware (See “Prepare for
Chromatographic Checkout” on page 107.)
2 Verify the following:
• Chromatographic-grade gases plumbed and configured:
helium as carrier gas, air as oxidizer, and oxygen as ozone
supply gas.
• Ozone supply gas moisture trap and other traps are in
date.
• Empty waste vials loaded in sample turret.
• 4-mL solvent vial with diffusion cap filled with isooctane
and inserted in Solvent A injector position.
• 4-mL solvent vial with diffusion cap filled with isooctane
and inserted in Solvent B injector position.
3 Replace consumable parts (liner, septum, traps, syringe, and
so forth) as needed for the checkout. See “Prepare for
Chromatographic Checkout” on page 107.
4 Install the evaluation column. (See the procedure for in the
GC Maintaining Your GC manual.)
• Bake out the evaluation column for at least 30 minutes at
180 °C. (See the procedure for in the GC Maintaining
Your GC manual.)
• Configure the column.
5 Check the detector baseline output. The output should be
below 150 pA and relatively stable, assuming a
well-stabilized system with the column oven at 50 °C.
However, a new burner (or a burner with a new ceramic
tube) can have a very high baseline after first ignition. In this
case, the baseline should gradually decrease, depending on
SCD and NCD User Manual
109
7
Performance Verification
burner cleanliness. Noise will also greatly decrease over time.
For a well-stabilized system, noise measured by Agilent
OpenLAB CDS should be approximately 5 display units or
less.
Checkout can continue before the baseline becomes
completely stable.
6 Create or load a method with the parameter values listed in
Table 14.
Table 14
SCD Checkout conditions
Column and sample
Type
DB-1, 30 m × 0.32 mm × 1 µm
(123-1033)
Sample
SCD checkout 5190-7003
Column flow
3.5 mL/min helium
Column mode
Constant flow
Split/splitless inlet
Temperature
250 °C
Mode
Splitless
Purge flow
80 mL/min
Purge time
0.7 min
Septum purge
3 mL/min
Gas saver
Off
Multimode inlet
Mode
Splitless
Inlet temperature
250 °C
Purge time
0.7 min
Purge flow
80 mL/min
Septum purge
3 mL/min
Gas saver
Off
Cool on-column inlet
Temperature
Oven Track
Septum purge
15 mL/min
Detector
Base temperature
110
280°C
SCD and NCD User Manual
Performance Verification
Table 14
7
SCD Checkout conditions (continued)
Burner temperature
800 °C
Upper H2 flow
38 mL/min
Lower H2 flow
8 mL/min
Oxidizer flow
50 mL/min, Air
O3 Generator
On
O3 Generator flow
On
Vacuum pump
On
FID-SCD Tandem settings
FID temp
350 °C
FID hydrogen flow
35 mL/min
FID air flow
500 mL/min
FID N2 makeup flow
20 mL/min
SCD oxidizer flow
0
SCD upper H2 flow
40 mL/min
Lower H2 flow
Not applicable for FID-SCD
Oven
Initial temp
50 °C
Initial time
3.0 min
Rate 1
25 °C/min
Ramp 1 temp
160 °C
Ramp 1 hold time
2 min
Post run temp
50 °C
ALS settings (if installed)
SCD and NCD User Manual
Sample washes
2
Sample pumps
6
Sample wash volume
8 µL (maximum)
Injection volume
1 µL
Syringe size
10 µL
Solvent A pre washes
0
Solvent A post washes
3
Solvent A wash volume
8 µL (maximum)
Solvent B pre washes
0
111
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Performance Verification
Table 14
SCD Checkout conditions (continued)
Solvent B post washes
3
Solvent B wash volume
8 µL (maximum)
Injection mode (7693A)
Normal
Airgap Volume (7693A)
0
Viscosity delay
0
Solvent Wash Draw Speed (7693A)
150
Solvent Wash Dispense Speed
(7693A)
1500
Sample Wash Draw Speed (7693A)
150
Sample Wash Dispense Speed
(7693A)
1500
Inject Dispense Speed (7693A)
3000
Plunger speed (7683)
Fast, for all inlets except COC.
PreInjection dwell
0
PostInjection dwell
0
Manual injection
Injection volume
1 µL
Data system
Data rate
5 Hz (Front detector, SCD)
7 If using a data system, prepare the data system to perform
one run using the loaded checkout method. Make sure that
the data system will output a chromatogram. If not using a
data system, create a one sample sequence using the GC
keypad.
8 Start the run. If performing an injection using an
autosampler, start the run using the data system or press
[Start] on the GC. If performing a manual injection (with or
without a data system):
a Press [Prep Run] to prepare the inlet for splitless injection.
b When the GC becomes ready, inject 1 μL of the checkout
sample and press [Start] on the GC.
112
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Performance Verification
7
The following chromatogram shows typical results for a new
detector with new consumable parts installed. Note that the
response for a tandem FID-SCD installation will be
approximately 1/10 of the response shown in this example
due to the reduced amount of sample that reaches the SCD.
2000
7 .8 0 6
tert-butyldisulÀde
2500
diethyl disulÀde
6 .1 0 1
SCD1 A, Front Signal (C:\CHEM32\2\DATA\XCD-DATA-FEB2015\SCD\EXAMPLE.D)
1500
1000
500
0
2.5
SCD and NCD User Manual
5
7.5
10
min
113
7
Performance Verification
Check NCD Performance
1 Gather the following:
• Evaluation column, HP-5 30 m × 0.32 mm × 0.25 μm (part
number 19091J-413)
• NCD performance evaluation (checkout) sample
(5190-7002): 3-methylindole 10.0 ± 0.1 mg/L,
9-methylcarbazole 14.1 ± 0.1 mg/L, and nitrobenzene
9.51 ± 0.05 mg/L in isooctane.
• Chromatographic-grade isooctane
• 4-mL solvent and waste bottles or equivalent for
autoinjector
• 2-mL sample vials or equivalent for sample
• Inlet and injector hardware (See “Prepare for
Chromatographic Checkout” on page 107.)
2 Verify the following:
• Chromatographic-grade gases plumbed and configured:
helium as carrier gas, oxygen as oxidizer and ozone supply
gas.
• Ozone supply gas moisture trap and other traps are in
date.
• Empty waste vials loaded in sample turret.
• 4-mL solvent vial with diffusion cap filled with isooctane
and inserted in Solvent A injector position.
• 4-mL solvent vial with diffusion cap filled with isooctane
and inserted in Solvent B injector position.
3 Replace consumable parts (liner, septum, traps, syringe, and
so forth) as needed for the checkout. See “Prepare for
Chromatographic Checkout” on page 107.
4 Install the evaluation column. (See the procedure for in the
GC Maintaining Your GC manual.)
• Bake out the evaluation column for at least 30 minutes at
270 °C. (See the procedure for in the GC Maintaining
Your GC manual.)
• Configure the column.
5 Check the detector baseline output. The output should be
below 150 pA and relatively stable, assuming a
well-stabilized system with the column oven at 50 °C. (A
negative baseline can be acceptable.).
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7
Performance Verification
However, a new burner (or a burner with a new quartz tube)
can have a very high baseline after first ignition. In this case,
the baseline should gradually decrease, depending on burner
cleanliness. Noise will also greatly decrease over time. For a
well-stabilized system, noise measured by Agilent OpenLAB
CDS should be approximately 4 display units or less.
Checkout can continue before the baseline becomes
completely stable.
6 Create or load a method with the parameter values listed in
Table 15.
Table 15
NCD Checkout conditions
Column and sample
Type
HP-5, 30 m × 0.32 mm × 0.25 µm
(19091J-413)
Sample
NCD checkout 5190-7002
Column flow
2.2 mL/min
Column mode
Constant flow
Split/splitless inlet
Temperature
250 °C
Mode
Splitless
Purge flow
80 mL/min
Purge time
0.8 min
Septum purge
3 mL/min
Gas saver
Off
Multimode inlet
Mode
Splitless
Inlet temperature
250 °C
Initial time
0 min
Purge time
0.8 min
Purge flow
80 mL/min
Septum purge
3 mL/min
Gas saver
Off
Cool on-column inlet
Temperature
SCD and NCD User Manual
Oven Track
115
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Performance Verification
Table 15
NCD Checkout conditions (continued)
Septum purge
15 mL/min
Detector
Base temperature
280°C
Burner temperature
900 °C
Chiller temperature
On
H2 flow
3 mL/min
Oxidizer flow
8 mL/min, Oxygen
O3 Generator
On
O3 Generator flow
On
Vacuum pump
On
Oven
Initial temp
50 °C
Initial time
3.0 min
Rate 1
25 °C/min
Ramp 1 temp
250 °C
Ramp 1 hold time
2 min
Post run temp
50 °C
ALS settings (if installed)
116
Sample washes
2
Sample pumps
6
Sample wash volume
8 µL (maximum)
Injection volume
1 µL
Syringe size
10 µL
Solvent A pre washes
0
Solvent A post washes
3
Solvent A wash volume
8 µL (maximum)
Solvent B pre washes
0
Solvent B post washes
3
Solvent B wash volume
8 µL (maximum)
Injection mode (7693A)
Normal
Airgap Volume (7693A)
0
Viscosity delay
0
SCD and NCD User Manual
7
Performance Verification
Table 15
NCD Checkout conditions (continued)
Solvent Wash Draw Speed (7693A)
150
Solvent Wash Dispense Speed
(7693A)
1500
Sample Wash Draw Speed (7693A)
150
Sample Wash Dispense Speed
(7693A)
1500
Inject Dispense Speed (7693A)
3000
Plunger speed (7683)
Fast, for all inlets except COC.
PreInjection dwell
0
PostInjection dwell
0
Manual injection
Injection volume
1 µL
Data system
Data rate
5 Hz (Front detector, NCD)
7 If using a data system, prepare the data system to perform
one run using the loaded checkout method. Make sure that
the data system will output a chromatogram. If not using a
data system, create a one sample sequence using the GC
keypad.
8 Start the run. If performing an injection using an
autosampler, start the run using the data system or press
[Start] on the GC.If performing a manual injection (with or
without a data system):
a Press [Prep Run] to prepare the inlet for splitless injection.
b When the GC becomes ready, inject 1 μL of the checkout
sample and press [Start] on the GC.
SCD and NCD User Manual
117
Agilent Technologies
The following chromatogram shows typical results for a new
detector with new consumable parts installed.
9-methylcarbazole
9.947
7.800
5.859
4000
3-methylindole
nitrobenzene
NCD1 A, Front Signal (C:\CHEM32\2\DATA\XCD-DATA-FEB2015\NCD\EXAMPLE.D)
3000
2000
1000
0
0
2
4
6
8
Agilent Technologies, Inc.
Printed in USA
December 2015
10
min
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