Teledyne MX300-I Service Instructions

Portable Oxygen Monitor
OPERATING & SERVICE INSTRUCTIONS FOR
MX300-I
PORTABLE OXYGEN MONITOR
P/N M75707
REV 1
ECO # 04-0088
0086
TYPE B EQUIPMENT:
Equipment providing a particular degree
of protection against electric shock,
particularly regarding—
• Allowable LEAKAGE CURRENT
• Reliability of the protective earth
connection (if present).
Teledyne Analytical Instruments
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MX300-I
Copyright © 2002 Teledyne Analytical Instruments
All Rights Reserved
No part of this manual may be reproduced, transmitted, transcribed, stored in a
retrieval system, or translated into any other language or computer language in whole
or in part, in any form or by any means, whether it be electronic, mechanical, optical,
manual, or otherwise, without prior written consent of Teledyne Instruments,
Analytical Instruments, 16830 Chestnut Street, City of Industry, CA 91749-1580
FCC Statement
This equipment generates and uses radio frequency energy, and if not installed and
used in strict accordance with the manufacturer's instruction manual, may cause
interference to radio and TV communications. It has been type-tested and certified to
comply with the limits for a Class A, and exceeds limits for a Class B, computing
device pursuant to Subpart J of FCC Rules, which are designed to provide reasonable
protection against such interference when installed in a commercial and residential
environment. Operation of this equipment in a residential area may cause interference,
in which case the user, at his own expense, will be required to take whatever measures
may be required to correct the interference.
Note: The above statement is required by the FCC for any device
that incorporates microprocessors.
Warranty
Teledyne warrants that the goods are free from defects of material and of construction
for a period of 2 years from the date of shipment from Teledyne. The Class R-17MED
Micro-Fuel Cell is warranted for two years from the date of shipment from Teledyne.
The liability of Teledyne if any, shall be limited solely to the replacement and repair of
the goods and shall not include shipping costs or other incidental damages as defined in
Section 2-715 of the U.S. Uniform Commercial Code.
This warranty is null and void if any goods are subjected to misuse, negligence,
accident, or repairs other than those performed by Teledyne or an authorized service
center.
CAUTION:
FEDERAL LAW RESTRICTS THIS DEVICE TO SALE
BY OR ON THE ORDER OF A PHYSICIAN.
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Portable Oxygen Monitor
About This Manual
The MX300-I Operator's Manual provides both introductory and
detailed information for configuring and operating these instruments.
The manual takes you from the time you unpack the instrument until you
complete the first gas analysis. The bulk of the manual contains
operating procedures and information. There are also cautions,
warnings, and guidelines to ensure that your monitor operates normally
and to its full potential. A troubleshooting section is available to assist
you with common problems and a complete product specifications and
spare parts list is included as an appendix.
•
Chapter 1:
An introduction to the monitor and its
components, features and applications.
•
Chapter 2:
Step-by-step set-up procedures and
information.
•
Chapter 3:
A guide for daily operational maintenance and
troubleshooting.
•
Appendix:
Specifications and available spare part options
for the monitor, and detailed application
considerations to aid in troubleshooting, etc.
How To Use This Manual
This manual is designed to walk you through the initial set-up of
the MX300-I Portable Oxygen Monitor. After you have used it to
initially install your monitor, it becomes a quick reference guide to help
you with specific questions or operating problems.
Before you turning on the instrument, you are advised to read the
safety information on the next few pages and the information found in
Chapters 1 and 2. These chapters acquaint the user with the instruments
use and operation before placing it into operation.
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MX300-I
Safety Messages
Your safety and the safety of others are very important. Please
carefully read the following safety messages.
Safety message are indented to alert the user of potential hazards.
Each safety message is associated with a safety alert symbol. These
symbols are found in the manual and on the instrument. The definition
of these symbols is described below:
CAUTION: Refer to the instructions for details on the
specific danger. These caution symbols warn of specific
procedures, which if not followed could cause bodily Injury,
and/or damage the instrument.
WARNING: This symbol is use to alert the operator of a
condition that could cause bodily harm.
NOTE: Additional information and comments regarding a
specific component or procedure are highlighted in the form
of a note.
CAUTION:
THE MONITOR SHOULD ONLY BE USED FOR THE
PURPOSE AND IN THE MANNER DESCRIBED IN
THIS MANUAL.
IF YOU USE THE ANALYZER IN A MANNER OTHER
THAN THAT FOR WHICH IT WAS INTENDED,
UNPREDICTABLE BEHAVIOR COULD RESULT
POSSIBLY ACCOMPANIED WITH HAZARDOUS
CONSEQUENCES.
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Portable Oxygen Monitor
Table of Contents
Safety Messages .......................................................................... iv
List of Figures................................................................................ v
List of Figures.............................................................................. vii
List of Tables .............................................................................. viii
Introduction ................................................................................... 9
1.1 Applicable Standards
10
1.2 Features
11
1.3 Options
11
1.4 Applications
12
1.5 Theory of Operation
12
1.5.1 Sensor
13
1.5.2 Signal Processing
13
Operation ..................................................................................... 15
2.1 Setup
15
2.1.1 Sensor Installation or Replacement
16
2.1.2 Mounting
18
2.1.2.1 V-Mount Adapter Installation
18
2.1.2.2 Universal Mounting Clamp Installation
18
2.1.3 Battery Installation
19
2.1.3 Calibration
20
2.1.4 Alarms
22
2.1.5 Output 0-1 VDC or RS232
23
2.2 Use
25
2.2.1 Procedure
25
2.3 Gas Sampling
26
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MX300-I
2.3.1 Humidity
26
2.3.2 Temperature
27
2.3.3 Pressure
27
2.3.4 Discrepancy in Readings
28
2.3.5 Anesthetic Gases
28
2.3.5.1 Gases That Induce Reading Error
28
2.3.5.2 Care After Use in Nitrous Oxide
29
2.3.6 Cleaning
2.4 Do’s and Don’ts
30
30
Service Manual ............................................................................ 33
3.1 General Service Information
33
3.2 Overall Maintenance
33
3.3 Battery Maintenance
33
3.4 Sensor Maintenance
34
3.5 Calibration
34
3.6 Alarms
35
3.7 Gas Sampling
35
3.7.1 Humidity
35
3.7.2 Temperature
35
3.7.3 Pressure
36
3.7.4 Discrepancy in Readings
36
3.8 Troubleshooting
37
3.9 Watchdog
40
3.10 Other Problems with the Instrument
41
3.11 Return Authorization for Service
42
Appendix...................................................................................... 43
A.1 Specifications
43
A.2 Spare Parts List
44
A.3 Optional Accessories
44
Index............................................................................................. 47
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Portable Oxygen Monitor
List of Figures
Figure 1-1: MX300-I Front View ...................................................... 9
Figure 2-1: Installing the R17MED Sensor .................................... 16
Figure 2-2: Sensor Cable Connection to Monitor ......................... 17
Figure 2-3: Mounting the Sensor in the Tee Adapter..................... 17
Figure 2-4: V-Mount Adapter Installation ....................................... 18
Figure 2-5: Brass Insert for Universal Mounting Clamp ................. 18
Figure 2-6: Installing Batteries....................................................... 19
Figure 2-9: 0-1 VDC or RS 232 Digital Output Port ....................... 24
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MX300-I
List of Tables
Table 2-1: Oxygen Reading Error in a Mixture of Anesthetic Gas. 29
Table 3-1 Troubleshooting ............................................................ 37
Table 3-2 Error Codes................................................................... 40
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Portable Oxygen Monitor
Introduction
Introduction
Teledyne Analytical Instruments MX300-I Oxygen Monitor with
alarms here after referred to as MX300-I is a portable instrument that
provides fast and accurate oxygen monitoring and incorporates an
audio/visual alarm capability. These instruments are designed to monitor
up to 100% oxygen concentration in medical gas mixtures. Because they
are microprocessor-based, the MX300-I instruments have a unique
combination of features that make them very easy to use. The operator
interface is accomplished through a series of buttons located
conveniently on the front face of the instrument. The MX300-I front
face interface is shown in Figure 1-1.
Figure 1-1: MX300-I Front View
The LCD display consists of up to 3.5 characters plus a decimal
point indicator capable of displaying up to 105%. (See Section 1.3
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Introduction
MX300-I
Options for alternate display configuration). An integral battery life
indicator is displayed “on demand” with the MX300-I.
The instrument is powered by three AA alkaline batteries and is
designed to operate for 2000 hours in non-alarm state.
Oxygen analysis is linear across the single range of 0-100% using
Teledyne’s class R17MED oxygen sensor. A unique sensor failure
alarm is incorporated which warns the user if the sensor signal is lost or
low. When this occurs, the √ SENSOR display flashes. The alarm buzzer
can be silenced by pressing the ALARM SILENCE key. If the alarm
condition is not corrected within 115 seconds the alarm buzzer will
reactivate.
The MX300-I unit incorporates a dual concentration alarm with
individual user-defined set points. The set points are displayed on the
lower portion of the LCD display with the low alarm set point appearing
at the lower left and the high alarm appearing on the lower right of the
display. The alarm circuitry provides both an audible and visual alarm.
1.1 Applicable Standards
The MX300-I units are built to meet or exceed regulatory and
industry standards for use as a medical device. The instruments are
designed, built and tested with the following applicable standards:
ASTM F 1462: Specifications for Oxygen Analyzers
ASTM F 1463: Specifications for Alarm Signals
ISO 7767:
Oxygen Monitors for Monitoring patient
Breathing Mixtures
ISO 9703-1:
Anesthesia and Respiratory Care Alarm Signals
Part 1
ISO 9703-2:
Anesthesia and Respiratory Care Alarm Signals
Part 2
EN/IEC 60601-1-2: Medical Electrical Equipment—Part 1 General
Requirements for Safety. Electromagnetic
Compatibility Requirements and Test
MIL-STD-810E: Environmental Test Methods
EN/IEC 60601-1: Medical Electrical Equipment-General
Requirements for Safety
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Portable Oxygen Monitor
Introduction
1.2 Features
The MX300-I is a compact, versatile instrument capable of rapidly
measuring the oxygen content of an atmosphere or environment
accurately to ±2% over the range 0-100% oxygen. The following
features are standard on the MX300-I instruments:
•
Large easy to read 3 1/2 digit LCD display (see options)
•
Automatic LCD back lighting upon key press
•
Microprocessor controlled
•
Up/Down front panel controls
•
Sensor fail/disconnect alarm indicator (audible and visual)
•
Alarm silence button
•
2000 operating hours from 3 AA alkaline batteries
•
Battery status indicator
•
Stand for upright tabletop deployment
•
Hardware for pole clamping and V block support
•
Rugged high impact ABS construction
•
Splash resistant case.
•
Long life (36 months in air) class R17MED sensor
•
0-1 VDC digital output (optional RS-232)
•
FDA approved and cleared for CSA/CE marking
•
2 User defined set point controlled concentration alarms
•
Battery test function
1.3 Options
The following instrument options are available for the MX300-I
units:
•
A-Option—3-digit LCD display instead of 3 1/2 digit
•
B-Option—RS 232 digital output instead of 0-1VDC
Note: Contact the factory for retrofitting an existing instrument
for 3-digit LCD display. For RS-232 reconfiguration, see
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Introduction
MX300-I
Section 2.1.5.
In addition to the above instrument configuration options, the
following optional equipment is available for your instrument:
•
Universal Pole Mounting Clamp (P/N CP 2343)
•
V-Mount Pole Clamp (P/N CP 2344)
•
V-Mount Wall Adapter P/N B 647)
•
0-1 VDC Interface Cable (P/NB-75554)
•
RS 232 Interface Cable (P/N B-75555)
1.4 Applications
The MX300-I Portable oxygen analyzer is intended to continuously
measure and display the concentration of oxygen in a gas mixtures used
in medical applications such as Anesthesia, Respiratory therapy and is
intended for adult, pediatric and Neonatal populations.
The instruments may be used in verifying oxygen concentrations in
gas mixtures used in:
•
Anesthesia
•
Respiratory Therapy
•
Neonatal Care
1.5 Theory of Operation
The MX300-I monitor can be divided into two major functional
groups:
•
R17MED Oxygen Sensor
•
Signal Processing
The analyzer uses Teledyne Analytical Instruments Patented
R17MED oxygen sensor. The millovolt output signal from the sensor is
fed into the electronic signal processor, where it is used to calculate the
oxygen gas concentration and display it on the LCD screen. The data
from the sensor is compared to the alarm values set by the user, and
activates the audible and visual alarms if the oxygen level exceeds those
values. A unique sensor fail/disconnect alarm is incorporated in the
MX300-I to warn the user of a sensor problem. The√ SENSOR indicator
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Portable Oxygen Monitor
Introduction
is illuminated on the LCD and the audible and visual alarms are
activated whenever a fault is detected.
1.5.1 Sensor
The MX300-I uses the Teledyne Class R17MED disposable oxygen
sensor. The sensor is made up of a sensing cathode and anode (fuel)
immersed in electrolyte and packaged in a small plastic container.
Oxygen entering the sensor reacts with the anode and a proportional
current is collected at the sensing cathode, which is sent to the
electronics where it is converted into a digital signal and displayed on
the LCD Screen.
Attached to the R17MED sensor is a removable plastic diverter.
This diverter is used to facilitate the transport of gas mixtures through
the sensor. The diverter, packaged separately when shipped, is necessary
when the tee adapter is used to sample gas flowing through a tube.
The diverter is not necessary and should not be used when the
sensor is placed directly in a chamber, or when the sensor is used in
confined volume monitoring, such as incubators and inhalation tents.
CAUTION:
THE R17MED SENSOR CONTIANS A CAUSTIC
ELECTROLYTE AND LEAD. DO NOT TRY TO OPEN
THE SENSOR ASSEMBLY. CHECK THE SENSOR
REGULARLY FOR LEAKS. IF THE SENSOR IS
LEAKING, REPLACE IT. DO NOT TRY TO REPAIR IT.
CONTACT TELEDYNE FOR THE MATERIAL SAFETY
DATA SHEET RELATED TO HANDLING AND
DISPOSAL.
CAUTION:
REMOVE AND SAVE THE DIVERTER WHEN THE
SENSOR IS USED IN CONFINED VOLUME
APPLICATIONS.
1.5.2 Signal Processing
The electrical voltage developed in the sensor is sent to the electronics.
Processing includes amplification, conversion to digits, and comparison to
alarm set points if appropriate. Using a microprocessor allows for easier
setting of alarms, automatic calibration, and self-diagnosis.
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Introduction
MX300-I
The oxygen level is calculated and then displayed on the liquid
crystal display (LCD) on the front panel.
In the MX300-I monitor, user-programmed high and low alarm set
points are stored in random access memory (RAM), which resides within
the microprocessor. The oxygen level calculated by the microprocessor is
compared to these set points, and an alarm activated, if necessary.
The audio alarm is used for both the concentration alarms and the
sensor disconnects alarm. The user can manually bypass the
concentration alarm for a set amount of time. Pressing the ALARM
SILENCE key () will provide an audible alarm override for 115
seconds. After that, if the alarm condition still prevails, the audible
alarm will resume. The ALARM SILENCE key () can also be used
to interrupt the sensor disconnects audible alarm.
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Portable Oxygen Monitor
Operation
Operation
Note: Upon receipt, INSPECT THE ENTIRE UNIT FOR
DAMAGE. Check the unit and all included accessories for
broken or loose parts. If damaged, DO NOT USE. Notify
the shipper, and consult Teledyne Analytical Instruments.
Note: This equipment is internally powered using 3 AA batteries.
CAUTION:
THE MX300-I, OXYGEN SENSOR AND ASSOCIATED
HARDWARE ARE NON-STERILE DEVICES. DO NOT
AUTOCLAVE THE INSTRUMENT OR SENSOR, AS
THIS WILL DAMAGE THE EQUIPMENT.
2.1 Setup
The MX300-I Portable Oxygen Monitor is suitable for use in many
medical applications. The unit is equipped with a stand and can be used
on a tabletop or wall mounted using mounting bracket. An optional pole
mount clamp is also available.
To set up and use your MX300-I monitor:
1. Install the sensor.
2. Install the batteries.
3. Calibrate the unit.
4. Set the alarms.
The control keys are designed for easy operation. A LOCK/UNLOCK
key has been supplied to prevent accidental changes to critical settings. This
eliminates unwanted changes in calibration or alarm settings from accidental
touching or bumping of the keys. To further reduce the possibly of incorrect
adjustments at least two keys must be pressed in order to modify a critical
calibration or alarm set point value.
Note: The ALARM SILENCE () and BATT TEST key continue
to operate normally when the lock feature is activated.
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Operation
MX300-I
2.1.1 Sensor Installation or Replacement
Note: The R17MED oxygen sensor must be installed before the
oxygen analyzer/monitor can be operated
1. Remove the new sensor from its protective bag. Inspect the
sensor for damage or electrolyte leakage. If the sensor is
damaged, obtain a replacement. Do not use the defective
sensor as it may damage the unit.
WARNING:
THE SENSOR ELECTROLYTE IS CAUSTIC. DO NOT
LET IT COME IN CONTACT WITH SKIN. IF IT DOES,
FLUSH AFFECTED AREA WITH WATER. DO NOT
ATTEMPT TO OPEN OR REPAIR THE SENSOR.
WARNING:
THE SENSOR ALSO CONTAINS LEAD. LEAKING OR
EXHAUSTED SENSORS SHOULD BE HANDLED AND
DISPOSED OF IN ACCORDANCE WITH LOCAL
REGULATIONS. CONTACT TELEDYNE FOR THE
MATERIAL SAFETY DATA SHEET
2. Plug one end of the coiled cable into the jack receptacle on the
back end of the R17MED sensor and secure in place with the
capture nut located at the base of the connector. See Figure 2-1.
Figure 2-1: Installing the R17MED Sensor
3. Plug the other end of the coiled cable into the receptacle located on
the right side of the unit and secure it in place using the capture nut.
See Figure 2-2.
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Portable Oxygen Monitor
Operation
Figure 2-2: Sensor Cable Connection to Monitor
Note: When the MX300-I instrument is used for diffusion
sampling (i.e., incubators, tents, etc.), the plastic flow
diverter must be removed from the R17MED sensor. If the
sensor is used in breathing circuits, etc, the diverter must
be used as shown in Figure 2-3.
Figure 2-3: Mounting the Sensor in the Tee Adapter
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Operation
MX300-I
2.1.2 Mounting
The MX300-I can be mounted in several ways depending on the
optional equipment ordered at the time of purchase. See Section 1.3.
2.1.2.1 V-MOUNT ADAPTER INSTALLATION
The V-Mount Adapter consists of a matching plastic plate with
integral V-grooves that attach to the rear of the instrument.
To install V-Mount Adapter remove battery compartment door by
prying up the hinged latch at the bottom of the cover, then slide the
adapter plate into grooves provided in rear case. Replace the battery
compartment door and secure door latch. See Figure 2-4.
Note: The door latch is a tight fit onto the battery cover. Use a
coin to gently pry up the latch.
Figure 2-4: V-Mount Adapter Installation
2.1.2.2 UNIVERSAL MOUNTING CLAMP INSTALLATION
The Universal Mounting Clamp is supplied with a 1/4-20 screw for
securing the clamp to the rear of the instrument. A threaded brass insert is
installed on the back of the instrument for this purpose. See Figure 2-5.
Figure 2-5: Brass Insert for Universal Mounting Clamp
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Portable Oxygen Monitor
Operation
2.1.3 Battery Installation
Note: Three “AA” alkaline batteries must be installed in the unit
before the monitor will operate. The unit must be
recalibrated whenever new batteries are installed and
the HI and LOW alarm set points must be reset to the
desired values
To install the batteries:
1. Turn the unit off (if it is on).
2. Hold the instrument face down in the palm of your hand. Use
a coin to pry up the latch that secures the battery
compartment door. Remove the battery compartment door.
CAUTION:
IMPROPER INSTALLATION OF THE BATTERIES
MAY RESULT IN DAMAGE TO THE UNIT AND
BATTERIES.
Note: Use alkaline batteries only. Other battery types will
produce erroneous battery test readings.
3. Install 3 “AA” alkaline batteries into the holder as shown in
Figure 2-6. Each battery has its own slot. To insure proper
polarity, place the bottom (flat) or negative end of the battery
in the end of the holder marked “–”. Place the top (button) or
positive end of the battery in the end of the holder marked
“+”. Do this for each battery.
Figure 2-6: Installing Batteries
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Operation
MX300-I
4. Re-install the battery compartment door. When the unit is
first turned on the display will momentarily display all LCD
segments. During this period diagnostic tests are being
conducted to insure the circuits are functioning correctly.
The unit will activate the audible and visual alarms for about
1 second. The LCD will flash continuously indicating the
unit is in the unlocked position ready for calibration.
Note: When batteries are first installed or power is lost for any
reason the instrument defaults to the calibration mode. All
keys except the CAL and ON/Off (I/O) keys are inoperable
until a successful calibration is achieved.
5. To test the batteries. Press the BATT TEST key once. The
battery display, located below the oxygen readout display,
should show a bar graph of the remaining life to the batteries.
In the case of fresh batteries, it should illuminate all 5
segments from the left to the right end of the bar.
2.1.3 Calibration
The MX300-I should be calibrated before each use and every 8
hours to maintain accuracy.
Whenever new batteries are installed or removed for
any reason, the oxygen monitor defaults to the calibration
mode with the LCD display flashing 00.0. Only the CAL
and ON/OFF (I/O) keys are functional at this point. The
alarm set points will also need to be reset after calibration
is completed.
Note: For first time and for routine maintenance
calibrations, make sure the sensor and sensor
cable are installed correctly before attempting
to calibrate the instrument
To calibrate the instrument (See Figure 2-7):
1. Turn the unit on by pressing the ON/OFF (I/O)
key.
Figure 2-7: Calibration Sequence
2. Check the batteries by pressing the BAT key.
3. If the LCD is not flashing, press the LOCK/UNLOCK key to
unlock the keys. LCD will flash indicating changes can be
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Portable Oxygen Monitor
Operation
made to the settings. If the batteries have just been installed
the LCD will flash 00.0
4. As with most oxygen analyzer(s) the highest level of
accuracy is achieved when calibration is conducted using
100% oxygen. After installing the flow diverter as noted in
Section 2.1.1, insert the sensor into the plastic tee and
connect to a supply of pure dry oxygen flowing at 1-2 liters
per minute.
Note: An accessory calibration assembly (P/N C53790) is
available from Teledyne for use with the R17MED sensor
5. Wait about 20 seconds to insure the sample line is completely
purged with the calibration gas. Press the CAL key. The
LCD will count down from 9 to 0. During this time the
microprocessor is measuring the sensor output to determine
the gas concentration and selects the calibration range i.e.
100% or 20.9%. When the calibration is complete the LCD
will display the gas value. Press the LOCK/UNLOCK key to
save the calibration data.
Note: The MX300-I can only be calibrated using 100% oxygen or
room air 20.9%. Improper calibration or use of other gas
concentrations will activate the √ SENSOR indicator. To
repeat the calibration press the LOCK/UNLOCK key and
press the CAL key.
6. Remove the sensor from the oxygen supply and confirm the
LCD reads less than 22% in room air. It is not necessary for
it to read exactly 20.9%.
7. It is important to perform the calibration carefully and
thoroughly, using calibration gases that are free from
contaminates. Wait for a stable reading before locking in
calibration point. The accuracy of the instrument is only as
good as the procedure used to calibrate it.
Note: A single point air calibration is not recommended unless
the sensor can be exposed to a known source of fresh
outdoor air. Hospital room air is often enriched with
excess oxygen, which will introduce errors into the
calibration. Air calibration should only be used for
monitoring oxygen levels between 21% and 40% and
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Operation
MX300-I
should never be used where a high degree of accuracy
is needed.
Note: Never calibrate the unit in humidified gas, as water vapor
makes the oxygen concentration appear lower than it really
is. See Appendix: Humidity.
CAUTION:
DO NOT ADJUST THE CALIBRATION SETTINGS IN
AIR AFTER THE 100% CALIBRATION, AS THIS WILL
CANCEL THE MORE ACCURATE 100%
CALIBRATION. THE 100% CALIBRATION MAY BE
REPEATED AS MANY TIMES AS DESIRED.
8. Adjust alarm set points to desired level according to the
procedures in Section 2.1.4.
9. Press the LOCK/UNLOCK key to hold settings. The unit is
now ready for use.
2.1.4 Alarms
Note: Before attempting to change the alarms it is necessary to
unlock the control keys by pressing the LOCK/UNLOCK
key. When pressed the display will start flashing.
To set the alarms on the MX300-I monitor (see Figure 2-8):
1. To set the HI alarm: Press the HI ALARM SET
key once. Press the UP and DOWN arrow key
until the desired value is displayed in the lower
right corner of the display.
Note: The HI and LO alarms may be defeated by
setting the HI alarm limit one step above
100%. The display will blink ALARM OFF
continually in this mode.
2. To set the LO alarm, press the LO ALARM SET
key once. Press the UP and DOWN arrow key to
select a value. A built-in safety feature will not
allow you to select a LO alarm value less than
18%.
Figure 2-8: Setting the Alarms
Note: The MX300-I Portable Oxygen Monitor is
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Portable Oxygen Monitor
Operation
designed to prevent crossing of HI/LO alarm settings. If you
attempt to set the LO alarm higher than the HI alarm, it will
push the HI alarm setting up as you continue to rise the LO
alarm set point. This also applies when attempting to set the
HI alarm lower than the LO alarm.
3. To test the alarms, unlock the controls by pressing the
LOCK/UNLOCK key and then press ALARM TEST key. The
Lo alarm followed by the HI alarm will blink and the audible
visual alarm will are activated for about 1 second.
4. To silence the alarm buzzer for 115 seconds press the alarm
silence key () (flashing red indicator light).
5. To disable the alarms set the high alarm set point above 100%.
Note: When the alarm is in the OFF condition (set point above
100%) the ALARM OFF status message blinks slowly on
the LCD below the oxygen readout.
2.1.5 Output 0-1 VDC or RS232
The MX300-I provides signal outputs for use with recorders and
computers. The instruments are supplied standard with a 0-1 VDC
output. An optional 0-1 VDC Interface Cable (P/N B-75554) is
available from Teledyne for this purpose.
To connect the analyzer to an analog recording device:
1. Insert one end of the interface cable into the output port on
the side of the instrument. See Figure 2-9.
2. Insert the other end into the analog recorder device. Make
sure the device is equipped to handle a 0-1 VDC signal.
When properly calibrated, the output signal generated by the
analyzer is linear and proportional to the oxygen concentration.
If you requested Option-B (RS 232 digital output) at the time of
purchase, a digital RS 232 signal is output from the output port shown in
Figure 2-8. Use the optional RS 232 Interface Cable (P/N B-75555)
available from Teledyne for connection to a standard RS 232 port on a
computer or other suitably equipped digital device.
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Operation
MX300-I
Figure 2-9: 0-1 VDC or RS 232 Digital Output Port
If your instrument is set for analog (0-1 VDC) output, you can
reconfigure it to use the digital output by changing a jumper on the
internal PC board.
To activate the digital output:
1. Remove the batteries and remove the five screws that hold the
case together.
2. Remove the rear case section leaving the PCB in the front half of
the case.
3. Remove jumper at position JP3 and reinstall it at position JP7.
4. Replace the rear cover and secure in place with five screws.
Install the batteries and recalibrate per Section 2.1.3.
CAUTION:
RECORDER/RS232 OUTPUT SIGNAL SHOULD ONLY
BE CONNECTED TO AN EN60601-1/IEC60606-1
APPROVED DEVICE.
To reconfigure the analyzer from a digital (RS 232) output to
analog (0-1 VDC) output, use the same procedure except in step 3
remove the jumper from JP7 and replace it at JP3.
Teledyne Analytical Instruments
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Portable Oxygen Monitor
Operation
2.2 Use
2.2.1 Procedure
Note: Prior to use, always test the batteries and alarms (if
applicable). Also check calibration, the sensor for leaks
and damage, and the alarm settings.
The AX/MX300-I instruments can be used to measure a gas
mixture for oxygen in two basic modes:
•
In the inhalation side of breathing circuit ahead of
antibacterial filters, humidifiers and medicating devices.
•
In confined volumes such as incubators or tents.
When monitoring for oxygen in breathing circuits, the flow diverter
must be used. The diverter should be screwed onto the threaded front
end of the R17MED sensor. A tee adapter (plastic, P/N A268, or metal,
P/N A283) should be placed into the circuit, and the above sensor
assembly plugged into the tee adapter. See Figure 2-1.
CAUTION:
CHECK THE BREATHING CIRCUIT FOR LEAKS. BE
CERTAIN THAT THE CIRCUIT DOWNSTREAM OF
THE SENSOR DOES NOT PRODUCE ANY
BACKPRESSURE OR RESTRICTION TO FLOW.
ERRORS IN READINGS WILL RESULT IF THIS IS
NOT FOLLOWED.
THE OXYGEN SENSOR IS A NON-STERILE DEVICE
AND SHOULD BE USED IN CONJUCTION WITH AN
ANTIBACTERIAL FILTER. ALWAYS INSTALL THE
SENSOR ON THE INSPIRED LINE AHEAD OF
FILTERS, HUMIDIFIERS AND MEDICATING DEVICES.
NEVER EXPOSE THE SENSOR TO PATIENT’S
EXHALED BREATH OR SECRETIONS UNLESS YOU
INTEND TO DISPOSE OF THE SENSOR AND FLOW
ADAPTER AFTER USE.
When monitoring for oxygen in confined volumes such as
incubators, hoods, etc., the flow diverter must be removed from the
Teledyne Analytical Instruments
25
Operation
MX300-I
R17MED sensor so that it does not interfere with the rapid exchange of
gases to and from the sensing surface of the sensor.
CAUTION:
FAILURE TO REMOVE THE DIVERTER IN THESE
APPLICATION AREAS WILL RESULT IN A MARKED
LOWERING OF THE RESPONSE TIME OF THE
SENSOR.
The R17MED sensor can be placed or hung inside incubators, tents,
etc. When it is necessary to thread the cable through a small hole in
order to gain access to the inside of a chamber, the cable should be
disconnected at the sensor, threaded through the hole, and reconnected
inside the chamber.
The LOCK/UNLOCK key can be used to lock out any accidental
interference to the front panel keys. The LOCK/UNLOCK key acts as a
toggle, pressing LOCK/UNLOCK once renders inactive all keys except
the ALARM SILENCE () and BATT TEST keys. Pressing
LOCK/UNLOCK a second time unlocks the keypad.
2.3 Gas Sampling
2.3.1 Humidity
Humidity does not directly affect the accuracy of the sensor's
measurement. However, when a nebulizer or other device is used to
increase moisture levels in gas mixtures, the moisture actually dilutes
the mixture. This dilution effect decreases the oxygen concentration.
For example, if an 80% oxygen gas mixture is humidified to
saturation at room temperature, the resulting gas mixture will contain
only 77.5% oxygen. Your portable oxygen monitor accurately measures
decreases in the oxygen concentration due to the dilution effects of
moisture added to gas mixtures.
As with all oxygen sensors, excessive condensation on the sensing
surface of the R17MED will block the diffusion of oxygen to the sensor,
rendering it inoperative. We recommend installing the sensor on the dry
side of the breathing circuit at all times.
Teledyne Analytical Instruments
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Portable Oxygen Monitor
Operation
2.3.2 Temperature
The R17MED oxygen sensor adjusts for ambient temperature
changes in the range of 0–40°C (32–106°F). Since the thermistor that
compensates for these changes is located in the rear of the sensor
assembly, it is important that gas mixtures, flowing over the front of the
sensor, be at room temperature. Reading errors may occur if hot gases
from a heated humidifier are directed past a sensor teed into a breathing
circuit.
A small thermal tracking error may be encountered in application
areas where the entire sensor assembly is placed in the gas mixture to be
analyzed (e.g., incubators). Holding the sensor in your hand for more
than a few minutes can also affect the temperature tracking which
appears as a slow drift on the LCD. No adjustments should be made
during this period since this error will be eliminated when both the
thermistor and sensing electrode have had sufficient time to come to
thermal equilibrium. This can take up to 2 hours.
2.3.3 Pressure
Virtually all gas sensors and monitors measure the partial pressure, not
the percentage, of the gas that they sense. The only time that these
instruments can accurately read percentages is when the total pressure does
not vary over time between calibrations and use. This is way it is important to
calibrate the MX300-I oxygen sensor at regular intervals. It is recommended
that the unit be calibrated prior to each use or every 8 hours.
When the sensor is connected to a ventilator circuit, the alternating
“breathing” pressure cycles generated by the ventilator will be sensed as
an increase in the oxygen percentage (especially if the sensor is fast
enough to sense the changes, as is the R17MED). In reality, the
percentage of oxygen is not changing; it is the total pressure that is
increasing producing a corresponding increase in the partial pressure of
oxygen. A one hundred centimeter of water pressure pulse will produce
a 0.11 atmosphere, or an 11% increase in the total and therefore partial
pressure of oxygen. Assuming that the sensor is fast enough to track this
pressure pulse, an un-pressurized reading of 50% oxygen will increase
to 55.3% if the sensor is subjected to a pressure cycle of 100cm H2O.
The reading will rise proportionally less for smaller pressures.
Teledyne Analytical Instruments
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Operation
MX300-I
2.3.4 Discrepancy in Readings
The MX300-I instrument should be used to measure the oxygen
concentration exiting another oxygen mixing device or life support
system (i.e., a blender, incubator or anesthesia machine). The
information obtained from the MX300-I should never be used to adjust a
life-support system, but should only be used as an indication that the life
support system or device may require service and/or calibration.
When a discrepancy in oxygen readings is detected, the oxygen
analyzers readings should be verified by checking the MX300-I battery
condition and calibration using 100% Oxygen. If the monitor can be
calibrated, the unit can be assumed to be in good working order and
capable of providing readings to specification. If, after reinstalling the
unit, the discrepancy in oxygen readings persists, the problem is most
likely elsewhere (i.e., flow blockage, primary device error, etc.). Further
investigation should be made until the discrepancy in readings is
resolved. The troubleshooting section of this manual may provide
additional assistance in locating the problem.
Note: The MSDS on this material is available upon request
through the Teledyne Environmental, Health and Safety
Coordinator. Contact at (626) 934-1592
2.3.5 Anesthetic Gases
2.3.5.1 GASES THAT INDUCE READING ERROR
When using the R17MED sensor in the presence of anesthetic gases
such as Halothane, the oxygen reading may fall (see Table below). The
magnitude of this error will depend upon the level of oxygen and the
duration of exposure.
The anesthetic agents listed in the following table (Halothane,
Enflurane, Isoflurane, Sevoflurane, and Desflurane) were vaporized into
a stream of 30% oxygen / 70% nitrous oxide, and the resulting drops in
oxygen level after an exposure of approximately two hours were noted.
Exposures in excess of two hours may produce slightly greater
errors. The errors listed are typical for all oxygen sensors such as the
R17MED. Exposing the sensor to air or gases that do not contain
anesthetic agents for a period of time equal to or greater than the exposure
interval will eliminate the reading error in most cases.
Teledyne Analytical Instruments
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Portable Oxygen Monitor
Operation
Table 2-1: Oxygen Reading Error in a Mixture of Anesthetic Gas
Gas or Vapor Level
(Balance: Mixture of 30% O2 / 70% N2O, except where noted)
Gas or Vapor
Test Level
Oxygen Reading
Error
Helium
50%, balance O2
0%
Nitrous Oxide
80%, balance O2
0%
Carbon Dioxide
10%, balance O2
0%
Halothane
4%
< 1.5% O2 *
Enflurane
5%
< 1.5% O2 *
Isoflurane
5%
< 1.5% O2 *
Sevoflurane
5%
< 1.5% O2 *
Desflurane
15%
< 1.5% O2 *
* Errors are approximate and may vary based on exposure times and
concentrations.
These performances meet or exceed the requirements of ISO 7767:
1997 (E).
CAUTION:
THE MX300-I SHOULD NOT BE USED IN THE
PRESENCE OF FLAMMABLE ANESTHETICS SUCH
AS DIETHYL ETHER OR CYCLOPROPANE.
CAUTION:
THE MX300-I, OXYGEN SENSOR AND ASSOCIATED
HARDWARE ARE NON-STERILE DEVICES. DO NOT
AUTOCLAVE THE INSTRUMENT OR SENSOR, AS
THIS WILL DAMAGE THE EQUIPMENT.
2.3.5.2 CARE AFTER USE IN NITROUS OXIDE
CAUTION:
THE R17MED SENSOR SHOULD NOT BE LEFT IN
NITROUS OXIDE MIXTURES ANY LONGER THAN
ABSOLUTELY NECESSARY.
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Operation
MX300-I
After exposure to nitrous oxide mixtures, the sensor should be left
in 100% oxygen overnight (e.g., left in a breathing circuit that has been
flushed with pure oxygen). If this is not practical, when using the Tee,
remove the plastic flow diverter and leave the sensor in room air. If the
oxygen reading continues to drop after each use in nitrous oxide the
sensor should be removed from service. If the sensor can no longer be
calibrated or if there is any sign of electrolyte leakage, the sensor should
be disposed of in accordance with local regulations and the Material
Safety Data Sheet (MSDS). Contact Teledyne for the Material Safety
Data Sheet.
2.3.6 Cleaning
The MX300-I and R17MED sensor are non-sterile devices.
The oxygen analyzer, oxygen sensor, and sensor interconnection
cable may be cleaned by wiping the surfaces with isopropyl alcohol or a
mild cleaning solution.
Before placing instrument in operation make sure all surfaces are
dry and unit is properly calibrated.
When cleaning, do not allow liquids or moisture to enter the
instrument or sensor internal cavities. Do not allow the cleaning solution
to come in contact with the electrical connections. Do not immerse the
instrument, oxygen sensor or sensor interconnection cable in water or
any other liquid.
Do not expose the instrument, oxygen sensor and interconnection
cable to steam, ethylene oxide, or radiation sterilization.
2.4 Do’s and Don’ts
– DO –
•
Read all of the directions before using for the first time.
•
Calibrate every 8 hours or before every use.
•
Visually inspect the sensor for leakage before each use.
•
Calibrate using 100% oxygen and check in air.
•
Check the HI and LO alarm settings prior to each use.
Teledyne Analytical Instruments
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Portable Oxygen Monitor
Operation
•
Test batteries regularly and replace when battery indicator
shows low battery (no bars remaining)
•
Make sure keys are locked by using the LOCK/UNLOCK
key feature.
•
Keep the unit, sensor and connections dry, or on the dry side
of the breathing circuit.
•
Recalibrate after replacing the batteries.
•
Recalibrate after replacing the sensor.
•
Use properly installed alkaline batteries only.
•
Make sure the R17MED sensor is properly attached.
•
Remove the plastic flow diverter only when using the tee adapter.
•
Remove and save the plastic flow diverter when using the
sensor in non-flowing applications (incubators, tents, etc.)
•
Perform an alarm test before each use (press the ALARM
TEST key).
•
Clean the case with isopropyl alcohol or mild detergent only.
– DON’T –
•
Use this monitor if you suspect any malfunction.
•
Use the instrument in the presence of flammable gases.
•
Use anything but alkaline batteries.
•
Autoclave or freeze the sensor or instrument.
•
Open or try to repair a leaking or broken sensor.
•
Immerse the unit or sensor in any liquid.
•
Pass hot or cold gas mixtures over the sensor.
•
Adjust the reading in air after 100% calibration
•
Expose the unit to devices that produce high levels of radio,
short wave, microwave, x-ray, or high frequency
interference.
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Operation
MX300-I
•
Use cleaning agents or liquids in the cable receptacles or
around the battery compartment.
•
Place the unit itself in a water vapor-saturated environment.
•
Expose the LCD to excessive sunlight.
•
Expose the unit to a condensing water environment such as a
mist tent.
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Portable Oxygen Monitor
Service Manual
Service Manual
3.1 General Service Information
The Teledyne Model MX300-I Portable Oxygen Monitor is
designed to be robust yet compact in size. In order to achieve maximum
reliability in a microprocessor-based instrument, a single PC board is
used which relies exclusively on surface mount technology. Without
access to specialized probes and test equipment, troubleshooting and
repair of circuit board components are not feasible. A factory
replacement of the entire PC board is more cost effective than a field
repair of an individual component
With the exception of replacing the sensor or batteries there are no
user-serviceable components inside the unit. There are no
potentiometers or other adjustments to be made within this instrument. If
a problem arises with either of these models that cannot be corrected by
recalibration, changing the batteries or replacing the sensor as described
in the users manuals, contact your locale Representative or Teledyne for
assistance. When returning the unit to the factory for repair or
replacement. See Section 3.11 for instructions on obtaining a Return
Merchandise Authorization (RMA) number before sending a unit back
to Teledyne for repair.
3.2 Overall Maintenance
The MX300-I requires very little maintenance, other than
calibration, checking and changing the batteries and sensor, and cleaning
the plastic housing. Occasional cleaning of the plastic surface can be
done with isopropyl alcohol. Should any part of the instrument
malfunction or fail to perform, the unit should be removed from service.
There are no user-serviceable components within the instrument.
3.3 Battery Maintenance
DO: Test batteries regularly. (replace immediately when all 5 bars
are missing).
DO: Always use alkaline batteries.
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Service Manual
MX300-I
DO: Recalibrate after replacing batteries.
The MX300-I instrument incorporates a battery test feature that
provides the approximate amount of useful life remaining on the set of
batteries. Excessive alarm activation will wear down the battery faster
than usual.
The minimum detectable change in battery voltage corresponds to
an increment of about 50 hours, meaning that the battery voltage reading
may not change for several hours at a time.
If the monitor is not used for a period of 30 days or more, the
batteries should be removed prior to storage.
3.4 Sensor Maintenance
DO: check the sensor for damage or leaks before use.
DO: recalibrate after replacing the sensor.
DON’T: immerse the R17MED sensor in liquid.
DON’T autoclave the R17MED sensor.
DON’T: open or try to repair the sensor.
Before every use, the sensor, cable and connections should be
checked. Check the sensor for leaks and condensation. Check the cable
for splitting or cracked insulation. Make sure the connections are tight
and dry.
In the event that the sensor has been damaged. Contact your locale
Representative or Teledyne to receive a copy of the Material Safety Data
Sheet.
3.5 Calibration
Incorrect readings can often traced to improper calibration. The
MX300-I should be calibrated before each use and every 8 hours to
maintain accuracy. It must be calibrated whenever new batteries are
installed. Calibration using methods other than described below can lead
to improper operation and are discouraged.
Whenever new batteries are installed or removed for any reason,
the oxygen monitor defaults to the calibration mode with the LCD
display flashing 00.0. Only the CAL and ON/OFF (I/O) keys are
Teledyne Analytical Instruments
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Portable Oxygen Monitor
Service Manual
functional at this point. After calibration is completed, the alarm set
points will need to be reset.
To calibrate the instrument refer back to Section 2.1.3.
3.6 Alarms
To set the alarms on the MX300-I monitor, refer to Section 2.1.4.
3.7 Gas Sampling
3.7.1 Humidity
Humidity does not directly affect the accuracy of the sensor's
measurement. However, when a nebulizer or other device is used to
increase moisture levels in gas mixtures, the moisture actually dilutes
the mixture. This dilution effect decreases the oxygen concentration.
For example, if an 80% oxygen gas mixture is humidified to
saturation at room temperature, the resulting gas mixture will contain
only 77.5% oxygen. Your portable oxygen monitor accurately measures
decreases in the oxygen concentration due to the dilution effects of
moisture added to gas mixtures.
As with all oxygen sensors, excessive condensation on the sensing
surface of the R17MED will block the diffusion of oxygen to the sensor,
rendering it inoperative. We recommend installing the sensor on the dry
side of the breathing circuit at all times.
3.7.2 Temperature
The R17MED oxygen sensor adjusts for ambient temperature
changes in the range of 0–40°C (32–106°F). Since the thermistor that
compensates for these changes is located in the rear of the sensor
assembly, it is important that gas mixtures, flowing over the front of the
sensor, be at room temperature. Reading errors may occur if hot gases
from a heated humidifier are directed past a sensor teed into a breathing
circuit.
A small thermal tracking error may be encountered in application
areas where the entire sensor assembly is placed in the gas mixture to be
analyzed (e.g., incubators). Holding the sensor in your hand for more
than a few minutes can also affect the temperature tracking which
appears as a slow drift on the LCD. No adjustments should be made
Teledyne Analytical Instruments
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Service Manual
MX300-I
during this period since this error will be eliminated when both the
thermistor and sensing electrode have had sufficient time to come to
thermal equilibrium. This can take up to 2 hours.
3.7.3 Pressure
Virtually all gas sensors and monitors measure the partial pressure,
not the percentage, of the gas that they sense. The only time that these
instruments can accurately read percentages is when the total pressure
does not vary over time between calibrations and use. For this reason it
is important to calibrate the MX300-I oxygen sensor at regular intervals.
It is recommended that the unit be calibrated prior to each use or every 8
hours.
When the sensor is connected to a ventilator circuit, the alternating
“breathing” pressure cycles generated by the ventilator will be sensed as
an increase in the oxygen percentage (especially if the sensor is fast
enough to sense the changes, as is the R17MED). In reality, the
percentage of oxygen is not changing; it is the total pressure that is
increasing. Producing a corresponding increase in the partial pressure of
oxygen. A hundred centimeter of water pressure pulse will produce a
0.11 atmosphere, or an 11% increase in the total and therefore partial
pressure of oxygen. Assuming that the sensor is fast enough to track this
pressure pulse, an un-pressurized reading of 50% oxygen will increase
to 55.3% if the sensor is subjected to a pressure cycle of 100cm H2O.
The reading will rise proportionally less for smaller pressures.
3.7.4 Discrepancy in Readings
The MX300-I instrument should be used to measure the oxygen
concentration exiting another oxygen mixing device or life support
system (i.e., a blender, incubator or anesthesia machine). The
information obtained from the MX300-I should never be used to adjust a
life-support system, but should only be used as an indication that the life
support system or device may require service and/or calibration.
When a discrepancy in oxygen readings is detected, the oxygen
analyzers readings should be verified by checking the MX300-I battery
condition and calibration using 100% Oxygen. If the monitor can be
calibrated, the unit can be assumed to be in good working order and
capable of providing readings to specification. If, after reinstalling the
unit, the discrepancy in oxygen readings persists, the problem is most
likely elsewhere (i.e., flow blockage, primary device error, etc.). Further
Teledyne Analytical Instruments
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Portable Oxygen Monitor
Service Manual
investigation should be made until the discrepancy in readings is
resolved. The troubleshooting section of this manual may provide
additional assistance in locating the problem.
Note: The MSDS on this material is located in the Appendix. It is
also available upon request through the Teledyne
Environmental, Health and Safety Coordinator. Contact at
(626) 934-1592
3.8 Troubleshooting
The MX300-I oxygen monitor provides a variety of built-in safety
features that prevents its use when a fault is detected. When a unit displays
the message √ SENSOR and sounds the audible and visual alarm
continuously, it is an indication of a faulty connection between the sensor and
the unit or an expired or faulty sensor. To determine where the difficulty lies,
refer to the following guidelines in Table 3-1.
Table 3-1 Troubleshooting
Symptom
Why
What To Do
New sensor responds
slow or drifts.
If the sensor is new
and was just
removed from its
sealed bag it may
need to run for
several hours.
A) Wait 1–2 hours and
recalibrate.
Sensor will not read
below 22 % after
calibration in 100% O2.
Calibration in 100%
was invalid or the
room air is
contaminated with
excess oxygen.
A) Recalibrate using dry gas
making sure the reading
stabilizes before making
any adjustments.
B) Make sure that at least 6"
(30 cm.) of tubing is
attached to the exhaust
side of the tee adapter to
prevent back filling. O2 flow
rate should not exceed 5
l/min.
C) Oxygen concentration at the
sensor is significantly higher
than 21%. Take the
instrument to a wellventilated area and check
Teledyne Analytical Instruments
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Service Manual
MX300-I
Symptom
Why
What To Do
the reading again.
E) Try calibrating with a known
good sensor; if this fails, see
symptom "Reading drifts
over 2–3%..."
The sensor does not
react to changes in
oxygen concentration,
or the readings are
unstable and drifting.
Water is condensing
on the sensing
surface.
Electrical interference
is disrupting the
electronics
A) Remove the sensor from tee
adapter and unscrew the
plastic flow diverter. Using
absorbent tissue or cotton
swab, gently wipe off sensing
surface inside threaded
portion of sensor assembly.
B) Relocate unit away from
sources of electrical noise
such as cauterizing equipment
and two-way radios.
The display is flashing
√ SENSOR
The unit has detected
a fault in the signal
from the sensor.
Sensor has expired.
The sensor has been
exposed to a gas
containing little or no
oxygen.
A) Check sensor cable
connections and make sure
they are completely
inserted into the mating
connector and the capture
nut is firmly in place.
B) Expose the sensor in 100%
O2 and check calibration.
C) The sensor output has
fallen to a level where it is
no longer usable. Replace
sensor.
The oxygen reading
fluctuates or appears to
be incorrect.
Like all O2 sensors,
the R17MED detects
the changes in the
partial pressure of
O2.
A) During calibration, make
sure there is no restrictions
on exhaust side of sensor. If
the reading changes with
flow, the sensor is
pressurized or there may be
a leak in the system.
B) If a high degree of accuracy
is desired, or the
concentration of O2 is in
excess of 40%, calibration
with 100% is recommended.
C) If humidified gas is used to
Teledyne Analytical Instruments
38
Portable Oxygen Monitor
Symptom
Service Manual
Why
What To Do
ventilate the patient, water
vapor actually dilutes the
gas. See Appendix:
Humidity, Temperature.
D) If a blender is used, check
its calibration. See
Appendix: Discrepancy in
Readings.
The unit has stopped
working and the LCD is
displaying
alphanumeric figures.
The MX300-I
instruments are
equipped with an
electronic "watch dog,"
which monitors the
circuitry within the unit
for potential faults and
renders the unit
inoperable until the
condition is corrected.
(See Watch dog
section below)
Several conditions
can activate the
"watch dog."
Dropping the unit,
poor battery
connections, and
radio frequency
interference are the
most common
causes. See the
watch dog section for
additional information
A) Disconnect the batteries and
inspect the contacts for
corrosion. Reconnect the
batteries. If the unit functions
properly, calibrate the unit
and reset the alarm values.
B) Try a new set of batteries.
C) Increase the distance
between the unit and any
source of radio frequency
interference. The sensor
cable is a prime source of
pickup as it can act like an
antenna. Relocate the
sensor cable and if possible
change its coiled length to
“de-tune” its antenna effect.
Placing the cable in a
different position may also
help.
Alarm sounds/flashes
continuously.
A) Readings are
outside alarm
limits.
A) Adjust high and low alarm
setting to be above and
below O2 value being
displayed.
No display.
A) Batteries expired.
A) Check/replace batteries.
B) Bad battery
connection.
B) Check battery connections.
The LOCK/UNLOCK
key is activated which
is preventing key
operation
A) Press LOCK/UNLOCK key
once. LCD will flash
indicating keys are active.
Keys inoperable/cannot
turn unit off
C) Calibrate.
Teledyne Analytical Instruments
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Service Manual
MX300-I
Symptom
Cannot adjust
calibration or alarm
settings
Why
What To Do
Critical settings require
two keys be pressed in
a specific order.
A) If display is not flashing
press lock key once to
activate keys. Press desired
function followed by the Up
and Down key.
LOCK/UNLOCK key is
active
Note: In the event that none of these procedures produce desired
results, remove the batteries and return the unit to Teledyne for
repair.
3.9 Watchdog
The MX300-I is equipped with a watchdog circuit that continuously
monitors the electronics for proper operation. If the watchdog detects a
failure, one of the following codes will appear on the LCD.
The error codes can appear on the LCD when batteries are first
installed, during normal operation or if the unit is subjected to extreme
shock. In some cases an additional digit is used in the error code to
supply additional information. For example, the error code 6 and 7 are
followed by another digit listed as (N) in Table 3.2. The error code 65
would indicate that a key is stuck and this key is the Silence key.
In addition to supplying visual error codes, the audio device will
beep a number of times to indicate the general error in case the display is
not functional.
NOTE: To reset the watchdog error code. Remove one battery for
5 seconds and replace. If the error persists contact your
local representative or Teledyne for assistance.
Table 3-2 Error Codes
Error Code
Audio Beeps
Error
Indeterminate
2
The watchdog timer has timed out indicating a
serious software error
30
3
Analog output is different from the expected value.
May indicate a shorted or over-loaded analog
output or a failure of the analog to digital converter
or digital to analog converter circuit.
Teledyne Analytical Instruments
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Portable Oxygen Monitor
Service Manual
50
5
The ADC circuit failed during POST.
6 (5)
6
A stuck key has been detected. The second digit
example (5) on the display shows which key is
stuck:
(There is no
indication of
which key is
stuck)
0 - Low Alarm
1 - Batt
2 - Cal
3 - Up
4 - Down
5 - Silence
6 - High Alarm
7 - Alarm Test
8 - Key Lock
7(2)
7
(There is no
indication of
the type of
DAC failure)
A failure has occurred during the automatic
calibration of the digital to analog converter (DAC)
circuit. The second digit example (2) shows the
type of digital to analog failure.
0 - Measurement
1 - High Test
2 - Low Test
3 - Offset Cal
4 - Gain Cal
3.10 Other Problems with the Instrument
Most other problems arise from either mechanical damage from the
instrument falling from a bench or table, or electronic component
failure. In these units, repair or troubleshooting the PCB or individual
component on the board is not feasible. It requires specialized test
equipment and probes not generally available to the public. Under most
circumstances a replacement of the entire PC Board is recommended.
The instrument must be returned to the factory for PCB installation.
Occasionally, depending on the environment of use, keys can
become stuck or function erratically due to contamination. Use a mild
Teledyne Analytical Instruments
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Service Manual
MX300-I
non-abrasive cleaner solution to periodically clean the keypad and
screen. An aerosol jet spray of the type commonly used to clean
computer keyboards can be used to dislodge dirt and accumulations
from the keypad.
The Error Code Table (Table 3-2) includes a description of certain fault
codes which are diagnostic of some common (usually electronic) problem
with the instrument. Some of these codes refer to specific components on the
PCB that are problematic or have failed. These codes are useful in reporting
a problem with your instrument to Teledyne Customer Service. If an error
code is indicated on your monitor record the number and report it to the
Customer Service Department at the address below.
3.11 Return Authorization for Service
For any service beyond sensor and battery replacement, the
instrument must be returned to the factory. A return merchandise
authorization (RMA) number must be obtained from Teledyne
Analytical Instruments prior to returning an instrument for service. You
can request a RMA number via email by contacting us at:
[email protected]
You can also contact us at the address below.
Customer Service Department
TELEDYNE Analytical Instruments
16830 Chestnut Street
City of Industry, CA 91749-1580 USA
Phone (626) 934-1500, Fax (626) 961-2538
Or via the web at: www.teledyne-ai.com
Teledyne Analytical Instruments
42
Portable Oxygen Monitor
Appendix
Appendix
A.1 Specifications
Range: 0-100% oxygen
Accuracy: +2% of full scale (at constant temperature
and pressure)
Response Time: 90% in less than 8 seconds at 25 °C
Battery Life: Approximately 2000 hr. continuous use in
a non-alarm condition
System Power: 3 AA alkaline batteries.
Sensor Type: Class R17MED
Expected Life: 36 months in air. (10 months when
continuously exposed to 100% oxygen)
Dimensions: 2.5" W × 1.25" D × 4.5" H (66 mm x 33mm × 111.5 mm)
Sensor Cable: Retracted: 2 ft / Extended: 10 ft.
Storage Temp. 10-30 °C (continuous), 5-50 °C
(Intermittent)
Operating Temp: 0-40 °C
Alarm ranges: HI alarm: 19 to 100 Percent
LO alarm: 18 to 99 %
Alarm accuracy: Alarm thresholds are digitally stored and
alarm affectivity is digitally compared
against the value calculated by the
microprocessor. Hence, the accuracy of the
alarms is the same as the accuracy of the unit
as specified above.
Teledyne Analytical Instruments
43
Appendix
MX300-I
A.2 Spare Parts List
QTY
1
PART NO
C43690-R17MED
3
1
1
1
1
1
1
1
1
B99
B69934
A268
B-74543
D-74459
C-74461
B-74462
B-74463
B-74466
DESCRIPTION
Micro-Fuel Cell R17MED with
flow diverter P/N A50057
“AA” size alkaline battery
Cable assembly
Tee adapter (22 mm)
Front panel assembly
Back panel
Battery door
Battery door lock
Mounting clip
Base assembly
A.3 Optional Accessories
1
1
1
1
1
1
1
1
A50057
CP2345
CP2344
B647
A51589
A51588
C53790
A284
1
1
1
1
A274
A283
B-75554
B-75555
R17MED flow diverter
Universal Pole Mounting Clamp
“V” mount Pole Clamp
“V” mount Wall Adapter
Sensor adapter cap, female (22 mm)
Sensor adapter cap, male (22 mm)
Calibration assembly
Universal adapter set for pediatric
circuits (15mm)
Tee adapter, autoclavable
Tee adapter, metal
0-1 VDC Interface Cable
RS 232 Interface Cable
Schematics are available on request.
____________________
A minimum charge is applicable to spare parts orders.
Teledyne Analytical Instruments
44
Portable Oxygen Monitor
Appendix
Note: Orders for replacement parts should include the part
number (if available) and the model and serial number of
the instrument for which the parts are intended.
Orders should be sent to:
TELEDYNE Analytical Instruments
16830 Chestnut Street
City of Industry, CA 91749-1580
Phone (626) 934-1500, Fax (626) 961-2538
Web: www.teledyne-ai.com
or your local representative.
Teledyne Analytical Instruments
45
Appendix
MX300-I
BLANK
Teledyne Analytical Instruments
46
Portable Oxygen Monitor
Index
Index
accessories, 44
accuracy, 43
address, 42, 45
alarm
setpoints, 22
alarm
setpoints, 22
alarm setpoints, 10, 14
alarm settings
crossover of, 23
ALARM SILENCE button, 10, 14, 15
ALARM TEST button, 23, 31
amplification, 13
analog output, 23
analysis range, 10, 43
anesthetic gas, 28
anode, 13
audio alarm, 14
BATT TEST button, 15, 20
batteries, 10, 19
battery compartment, 19
battery installation, 19
battery status indicator, 10
battery test, 34
breathing circuits, 25
cable, 16
calibration, 20, 21, 34
calibration interval, 27, 36
cathode, 13
CHECK SENSOR button, 10, 12, 37
concentration alarms, 10
confined volumes, 25
copyright, ii
current output. See output
diffusion sampling, 17
digital output, 24
dilution effects, 26, 35
display, 9
diverter, 13, 17, 25, 30
drift, 27, 35
electrolyte, 13
error, 28, 29
error code, 40
FCC, ii
features, 11
front panel, 9
front panel MX300-I, 9
galvanic cell, 13
HI alarm, 43
defeating, 22
humidity, 26, 35
intended use warning, iv
interface, 9
jumper, 24
linear, 10, 23
LO alarm, 43
LOCK/UNLOCK button, 15
maintenance, 33
moisture, 26, 35
mounting bracket, 15
nebulizer, 26, 35
nitrous oxide, 29
optional accessories. See accessories
output, 12
output port, 24
oxygen sensor, 12
partial pressure, 27, 36
power, 15
power requirements, 10, 43
R17MED, 10, 12, 25, 29, 34
RAM, 14
reading discrepancy, 27, 36
reading error, 27, 28, 35
rear panel, 18
reconfiguring output, 24
resetting alarms, 10
response, 43
restriction on selling. See sale
restriction
safety information, iv
sale restriction, ii
sensor, 10, 12
sensor cable, 43
sensor failure alarm, 10
sensor life, 43
sensor maintenance, 34
Teledyne Analytical Instruments
47
Index
MX300-I
sensor mounting, 17
set up, 15
setpoints. See alarm setpoints
signal output, 23
signal processing, 13
signal processor, 12
spare parts listing, 44
specifications, 43
stand, 15
standards, 10
storage, 34
tables listing, viii
tee adapter, 25
Teledyne address, 42, 45
temperature, 26, 35
temperature tracking, 27, 35
thermal equilibrium, 27, 36
thermal tracking error, 27, 35
thermistor, 26, 35
troubleshooting, 37
type B equipment, i
ventilator, 27, 36
warranty, ii
watchdog circuit, 40
water vapor, 22
website address, 42, 45
Teledyne Analytical Instruments
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