m_hmp155a
Model HMP155A Temperature
and Relative Humidity Probe
Revision: 10/13
C o p y r i g h t © 1 9 9 0 - 2 0 1 3
C a m p b e l l S c i e n t i f i c , I n c .
Warranty
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accidents of nature, or shipping damage. This warranty is in lieu of all other
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performed by Campbell such as programming to customer specifications,
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EXPRESSLY DISCLAIMS AND EXCLUDES ANY IMPLIED
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Table of Contents
PDF viewers: These page numbers refer to the printed version of this document. Use the
PDF reader bookmarks tab for links to specific sections.
1. Introduction .................................................................1
2. Cautionary Statements...............................................1
3. Initial Inspection .........................................................1
3.1
Ships With............................................................................................2
4. Quickstart ....................................................................2
4.1
4.2
Step 1 — Mount the Probe...................................................................2
Step 2 — Use Short Cut Program Generator for Windows (SCWin)
to Program Datalogger and Generate Wiring Diagram ....................4
5. Overview......................................................................6
6. Specifications .............................................................8
6.1
6.2
Temperature Sensor ...........................................................................10
Relative Humidity Sensor ..................................................................10
7. Installation .................................................................11
7.1
7.2
7.3
7.4
Siting ..................................................................................................11
Assembly and Mounting ....................................................................11
Wiring ................................................................................................11
Programming......................................................................................13
7.4.1 CR1000 Program Using Single-Ended Measurement
Instructions Using SW12V on Datalogger ..............................15
7.4.2 CR10(X) Program Using Single-Ended Measurement
Instructions Using SW12V on Datalogger ..............................15
7.5
Long Lead Lengths ............................................................................16
7.5.1 CR1000 Program Using Differential Measurement
Instructions Using SW12V on Datalogger ..............................17
7.5.2 CR10(X) Program Using Differential Measurement
Instructions Using SW12V on Datalogger ..............................18
7.6
Absolute Humidity .............................................................................19
7.6.1 CR1000 Program that Computes Vapor Pressure and
Saturation Vapor Pressure .......................................................20
7.6.2 CR10(X) Program that Computes Vapor Pressure and
Saturation Vapor Pressure .......................................................20
i
Table of Contents
8. Sensor Maintenance .................................................21
8.1
Periodic Maintenance ........................................................................ 22
8.1.1 Cleaning ..................................................................................... 22
8.1.2 Changing the Probe Filter........................................................... 22
9. Troubleshooting........................................................23
10. References.................................................................24
Appendix
A. Interfacing with HMP155A RS485 Output .............A-1
A.1
A.2
RS485 Interface Options ................................................................. A-1
SDM-SIO1 Serial I/O Module Interface Option.............................. A-1
A.2.1 Program Example for SDM-SIO1 Module............................... A-2
A.3 MD485 Multidrop Interface Option ................................................ A-4
A.3.1 MD485 Multidrop Interface Configuration.............................. A-8
A.3.2 CR1000 Example Program for use with MD485 ..................... A-9
Figures
4-1.
4-2.
6-1.
6-2.
8-1.
HMP155A and 14-plate radiation shield on a tripod mast .................. 3
HMP155A and 14-plate radiation shield on a CM200-series
crossarm........................................................................................... 3
Probe dimensions ................................................................................ 8
Wiring of HMP155A 8-pin connector................................................. 9
Changing the filter............................................................................. 22
5-1.
7-1.
7-2.
7-3.
7-4.
7-5.
7-6.
7-7.
7-8.
8-1.
Recommended Lead Lengths .............................................................. 7
Connections for Single-Ended Measurements................................... 12
Connections for Differential Measurements...................................... 13
Power Connections using SW12V Power Switch ............................. 13
Parameters for Temperature .............................................................. 14
Parameters for Relative Humidity ..................................................... 14
Wiring for Single-ended Measurement Examples............................. 14
Wiring for Differential Measurement Examples ............................... 17
Wiring for Vapor Pressure Examples ................................................ 19
Chemical Tolerances of HMP155A .................................................. 23
Tables
ii
Model HMP155A Temperature and
Relative Humidity Probe
1.
Introduction
The HMP155A probe monitors relative humidity (RH) for the range of 0 to
100% RH and temperature for the range of ─80° to +60°C. It can provide
reliable measurements for a wide range of applications, as part of a weather
station system or as a single instrument. All Campbell Scientific dataloggers
are compatible.
Before using the HMP155A, please study
•
•
•
Section 2, Cautionary Statements
Section 3, Initial Inspection
Section 4, Quickstart
More details are available in the remaining sections.
2.
3.
Cautionary Statements
•
Care should be taken when opening the shipping package to not damage or
cut the cable jacket. If damage to the cable is suspected, consult a
Campbell Scientific applications engineer.
•
Although the HMP155A is rugged, it should be handled as a precision
scientific instrument.
•
Do not touch the sensor element.
•
The black outer jacket of the cable is Santoprene® rubber. This
compound was chosen for its resistance to temperature extremes, moisture,
and UV degradation. However, this jacket will support combustion in air.
It is rated as slow burning when tested according to U.L. 94 H.B. and will
pass FMVSS302. Local fire codes may preclude its use inside buildings.
Initial Inspection
•
Upon receipt of the HMP155A, inspect the packaging and contents for
damage. File damage claims with the shipping company.
•
The model number and cable length are printed on a label at the
connection end of the cable. Check this information against the shipping
documents to ensure the correct product and cable length are received.
•
Refer to the Ships With list to ensure that parts are included (see Section
3.1).
1
Model HMP155A Temperature and Relative Humidity Probe
3.1
Ships With
The HMP155A ships with:
(1) Adjustment Screwdriver from manufacturer
(1) Calibration Sheet
(1) Instruction Manual or ResourceDVD
4.
Quickstart
4.1
Step 1 — Mount the Probe
Review Section 7, Installation, for complete instructions. To install the
HMP155A, you will need:
•
2
41005-5 Radiation Shield
1.
Loosen the split-nut on the bottom plate of the 41005-5 14-plate radiation
shield.
2.
Remove the yellow protective cap on the HMP155A, and insert the sensor
into the shield.
3.
Tighten the hex plug such that it compresses against the body of the
HMP155A to hold it inside the radiation shield.
4.
Attach the radiation shield to the tripod mast, crossarm, or tower leg using
the supplied U-bolt. See FIGURE 4-1 and FIGURE 4-2 for examples of
shield mounting.
5.
Route the cable to the datalogger, and secure the cable to the mounting
structure using cable ties.
Model HMP155A Temperature and Relative Humidity Probe
14-Plate
Radiation Shield
Split Nut
U-bolt
FIGURE 4-1. HMP155A and 14-plate radiation shield on a tripod mast
CM200 Series Crossarm
FIGURE 4-2. HMP155A and 14-plate radiation shield on a
CM200-series crossarm
3
Model HMP155A Temperature and Relative Humidity Probe
4.2
Step 2 — Use Short Cut Program Generator for Windows
(SCWin) to Program Datalogger and Generate Wiring
Diagram
The simplest method for programming the datalogger to measure the
HMP155A is to use Campbell Scientific’s SCWin.
1.
Open Short Cut and click on New Program.
2. Select a datalogger and scan interval.
4
Model HMP155A Temperature and Relative Humidity Probe
3.
Select HMP155 Temperature and Relative Humidity Sensor and
choose either constant power or panel switched power (uses less current),
then click the right arrow to add it to the list of sensors to be measured.
4.
Define the name of the public variables. Variables default to AirTC and
RH that hold the air temperature and relative humidity measurements.
Select the desired units of measure. Units default to Deg C.
5
Model HMP155A Temperature and Relative Humidity Probe
5.
5.
Choose the outputs for the AirTC and RH and then select finish.
6.
Wire according to the wiring diagram generated by SCWin.
Overview
The HMP155A Temperature and Relative Humidity probe contains a Platinum
Resistance Temperature detector (PRT) and a Vaisala HUMICAP® 180
capacitive relative humidity sensor.
The HMP155A outputs a 0 to 1 Vdc signal for temperature and relative
humidity that can be measured by all models of Campbell Scientific
dataloggers with model HMP155ACBL1 cable. The HMP155A also has
6
Model HMP155A Temperature and Relative Humidity Probe
RS485 outputs for temperature and relative humidity that can be interfaced to
the CR800, CR1000, and CR3000 dataloggers with model HMP155ACBL2
cable and the SDM-SIO1 Serial I/O Module as described in Appendix A.
Enabling the RS485 outputs will result in higher current drain than listed in the
specifications.
The HMP155A can be powered continuously or the power may be switched to
conserve battery life. The HMP155A consumes less than 3 milliamperes
current at 12 volts. Approximately 2 seconds is required for the sensor to
warm up after power is switched on. At measurement rates slower than once
per 5 seconds, the overall power consumption (datalogger and sensors) may be
reduced by switching power to the HMP155A. Most current Campbell
Scientific dataloggers have a built-in switched 12 volts that can be used to
control power.
HMP155 sensors purchased directly from Vaisala with serial
numbers < E4430001 require approximately 5 seconds warm up
time.
NOTE
The CR9000, CR510, CR500, CR7, CR10, and 21X dataloggers do not have a
built-in switched 12 volts. Users with these dataloggers can power the sensor
continuously or purchase the model SW12V to switch power.
The -L option on the model HMP155A Temperature and Relative Humidity
probe (HMP155A-L) indicates that the cable length is user specified. TABLE
5-1 gives the recommended lead length for mounting the sensor at the top of
the tripod/tower with a 2 foot crossarm. Lead length can be 2 feet shorter when
the sensor is mounted to the tripod mast / tower leg without a crossarm.
TABLE 5-1. Recommended Lead Lengths
CM6
CM10
CM110
CM115
CM120
UT10
UT20
UT30
11’
14’
14’
19’
24’
14’
24’
37’
The probe’s cable can terminate in:
•
•
Pigtails that connect directly to a Campbell Scientific datalogger
(option –PT).
Connector that attaches to a prewired enclosure (option –PW). Refer
to www.campbellsci.com/prewired-enclosures for more information.
7
Model HMP155A Temperature and Relative Humidity Probe
6.
Specifications
Features:
•
•
•
Well-suited for long-term, unattended applications
Accurate and rugged
Compatible with all Campbell Scientific dataloggers (including the
CR200(X) series)
Compatibility
Dataloggers:
CR200(X) series
CR800 series
CR1000
CR3000
CR5000
CR9000(X)
CR7X
CR510
CR10(X)
CR23X
21X
Operating Environment
Operating temperature range
for humidity measurement:
─80° to +60°C (─112° to +140°F)
Storage temperature range:
─80° to +60°C (─112° to +140°F)
Electromagnetic compatibility:
Complies with EMC standard EN61326-1,
Electrical equipment for measurement
control and laboratory use - EMC
requirements for use in industrial locations
Dimensions in mm (inches)
279 [10.98]
266 [10.47]
20 [0.79]
Ø12 [0.47]
40 [1.57]
86 [3.39]
24 [0.94]
FIGURE 6-1. Probe dimensions
8
Model HMP155A Temperature and Relative Humidity Probe
8-Pin Connector
0507-044
FIGURE 6-2. Wiring of HMP155A 8-pin connector
*HMP155ACBL1 Cable provided by Campbell Scientific
1=VOUT1 (yellow, temp)
2=no connection
3=AGND (white)
4=VOUT2 (blue, RH)
5=no connection
6=no connection
7=VCC (red)
8=GND (black)
- =SHIELD (clear)
*Note: HMP155ACBL2 for RS485 is described in Appendix A.
Mechanics
Filter:
Sintered PTFE
Housing material:
PC
Housing classification:
IP66
Weight:
86 g (3 oz)
Inputs and Outputs
Voltage outputs:
0 to 1 V
Average current consumption:
<3 mA (analog output mode)
Operating voltage:
7 to 28 Vdc
Settling time at power-up:
2s
9
Model HMP155A Temperature and Relative Humidity Probe
6.1
Temperature Sensor
Measurement range:
─80° to +60°C (─112° to +140ºF)
Accuracy with voltage output
at -80° to +20°C:
at +20° to +60°C:
±(0.226 - 0.0028 x temperature) °C
±(0.055 + 0.0057 x temperature) °C
See graph below
0804-032
Temperature sensor:
Response time (63 %) for additional
temperature probe in 3 m/s air flow:
6.2
Pt 100 RTD 1/3 Class B IEC 751
63% <20 s
90% <35 s
Relative Humidity Sensor
Measurement range:
Accuracy (including non-linearity,
hysteresis and repeatability)
at +15° to 25°C (59 to 77°F):
at ─20° to +40°C (─4° to 104°F):
at ─40° to ─20°C (─40° to ─4°F):
at +40° to +60°C (104° to 140°F):
at ─60° to ─40°C (─76° to ─40°F):
0 to 100% RH
±1% RH (0 to 90% RH)
±1.7% RH (90 to 100% RH)
± (1.0 + 0.008 × reading) % RH
± (1.2 + 0.012 × reading) % RH
± (1.2 + 0.012 × reading) % RH
± (1.4 + 0.032 × reading) % RH
Factory calibration uncertainty (+20°C):
±0.6% RH (0 to 40% RH)
±1.0% RH (40 to 97% RH)
(Defined as ±2 standard deviation
limits. Small variations possible,
see also calibration certificate.)
Humidity sensor:
HUMICAP®180R
Response time for HUMICAP®180R(C)
at 20°C in still air with sintered PTFE filter: 63%
90%
10
20 s
60 s
Model HMP155A Temperature and Relative Humidity Probe
NOTE
7.
The black outer jacket of the cable is Santoprene® rubber. This
compound was chosen for its resistance to temperature extremes,
moisture, and UV degradation. However, this jacket will support
combustion in air. It is rated as slow burning when tested
according to U.L. 94 H.B. and will pass FMVSS302. Local fire
codes may preclude its use inside buildings.
Installation
7.1
Siting
Sensors should be located over an open level area at least 9 m (EPA) in
diameter. The surface should be covered by short grass, or where grass does
not grow, the natural earth surface. Sensors should be located at a distance of
at least four times the height of any nearby obstruction, and at least 30 m
(EPA) from large paved areas. Sensors should be protected from thermal
radiation, and adequately ventilated.
Standard measurement heights:
1.5 m (AASC)
1.25 – 2.0 m (WMO)
2.0 m (EPA)
See Section 10 for a list of references that discuss temperature and relative
humidity sensors.
7.2
Assembly and Mounting
Tools Required:
•
•
•
•
1/2” open end wrench
small screw driver provided with datalogger
UV resistant cable ties
small pair of diagonal-cutting pliers
The HMP155A must be housed inside a radiation shield when exposed to solar
radiation. The 41005-5 14-plate radiation shield has a U-bolt for attaching the
shield to tripod mast / tower leg (FIGURE 4-1 in Section 4, Quickstart), or
CM200 series crossarm (FIGURE 4-2 in Section 4, Quickstart). The radiation
shield ships with the U-bolt configured for attaching the shield to a vertical
pipe. Move the U-bolt to the other set of holes to attach the shield it to a
crossarm.
7.3
Wiring
Connections to Campbell Scientific dataloggers are given in TABLE 7-1
through TABLE 7-3. The probe can be measured by two single-ended or
differential analog input channels (recommended for lead lengths > 6.1 m (20
ft.), see Section 7.5). The CR200(X)-series dataloggers only have single-ended
channels.
11
Model HMP155A Temperature and Relative Humidity Probe
CAUTION
When measuring the HMP155A with single-ended
measurements, the white and black leads must both be
connected to AG on the CR10(X) and CR500/CR510 or to
on the CR1000, CR5000, and CR23X. Doing otherwise
will connect the datalogger’s analog and power ground
planes to each other, which in some cases can cause
offsets on low-level analog measurements. To avoid 3 mA
flowing into analog ground, switch the sensor on/off for its
own measurement.
TABLE 7-1. Connections for Single-Ended Measurements
Color
Wire Label
CR10X
CR1000,
CR3000,
CR800,
CR5000,
CR23X
Yellow
Temp Signal
Single-Ended
Input
Single-Ended
Input
Single-Ended
Input
Single-Ended
Input
Single-Ended
Input
Blue
RH Signal
Single-Ended
Input
Single-Ended
Input
Single-Ended
Input
Single-Ended
Input
Single-Ended
Input
White
Signal
Reference
AG
AG
Black
Signal
Ground
AG
AG
Clear
Shield
G
G
Red
Power
SW12V
SW12V
12V/SW12V*
SW Power
SW12V
CR10, CR510,
CR500
21X, CR7
CR200(X)
12V/SW12V*
If using
SW12V,
jumper from
SW12V
Control
to Control Port
*On these dataloggers switched power is only available with the SW12V peripheral.
12
Model HMP155A Temperature and Relative Humidity Probe
TABLE 7-2. Connections for Differential Measurements
CR10X
CR1000,
CR3000,
CR800,
CR5000,
CR23X
CR10,
CR510,
CR500
21X, CR7
Color
Wire Label or
Description
Yellow
Temp Signal
Differential
Input – H
Differential
Input – H
Differential
Input – H
Differential
Input – H
Jumper to White
Differential
Input – L
Differential
Input – L
Differential
Input – L
Differential
Input – L
Blue
RH Signal
Differential
Input – H
Differential
Input – H
Differential
Input – H
Differential
Input – H
White
Signal Reference
Differential
Input – L
Differential
Input – L
Differential
Input – L
Differential
Input – L
Black
Signal Ground
G
G
G
Clear
Shield
G
Red
Power SW12V
12V/SW12V
G
12V/SW12V
12V/SW12V*
12V/SW12V*
If using
SW12V,
jumper from
SW12V
Control
to Control Port
*On these dataloggers switched power is only available with the SW12V Power Switch (ordered separately).
TABLE 7-3. Power Connections using SW12V Power Switch
HMP155A
SW12V Peripheral
Datalogger
Color
Description
Terminal
Wire
Red
Power
SW12V
Red
12 V
Black
Power Ground
GND
Black
G*
Green
Control Port
*The black wire of the SW12V should be connected to the type of datalogger
ground channel recommended for the HMP155A black wire as listed in
TABLE 7-1 and TABLE 7-2.
7.4
Programming
This section is for users who write their own datalogger programs. A
datalogger program to measure this sensor can be created using Campbell
Scientific’s SCWin. You do not need to read this section to use SCWin.
13
Model HMP155A Temperature and Relative Humidity Probe
The temperature and relative humidity signals from the HMP155A can be
measured using a single-ended analog measurement or a differential analog
measurement.
Use a single-ended analog measurement when the HMP155A signal lead
length is less than 6.1 m (20 ft.) or if the probe will be turned on and off under
datalogger control between measurements. For lead lengths greater than 6.1 m
(20 ft.) or when the probe will be continuously powered, use a differential
analog measurement. For a discussion on errors caused by long lead lengths
see Section 7.5.
NOTE
HMP155 sensors purchased directly from Vaisala with serial
numbers < E4430001 require approximately 5 seconds warm up
time.
The HMP155A output scale is 0 to 1000 millivolts for the temperature range of
─80° to +60°C (─112 to +140°F) and for the relative humidity range of 0 to
100%. Multipliers and offsets for converting voltage to temperature and
relative humidity are listed in TABLE 7-4 and TABLE 7-5 respectively.
TABLE 7-4. Parameters for Temperature
Units
Multiplier
(degrees mV-1)
Offset
(degrees)
Celsius
0.14
─80
Fahrenheit
0.252
─112
TABLE 7-5. Parameters for Relative Humidity
Units
Multiplier
(% mV-1)
Offset
(%)
Percent
0.1
0
Fraction
0.001
0
TABLE 7-6. Wiring for Single-ended
Measurement Examples
14
Color
Description
CR1000
CR10(X)
Yellow
Temperature
SE 2 (1L)
SE 3 (2H)
Blue
Relative Humidity
SE 1 (1H)
SE 4 (2L)
White
Signal Reference
AG
Jumper from
SW12V Control
C1
Red
Power
SW12V
SW12 V
Black
Power Ground
AG
Clear
Shield
G
Model HMP155A Temperature and Relative Humidity Probe
7.4.1 CR1000 Program Using Single-Ended Measurement Instructions
Using SW12V on Datalogger
'CR1000 program to measure HMP155A with single-ended measurements
Public AirTC
Public RH
DataTable(Temp_RH,True,-1)
DataInterval(0,60,Min,0)
Average(1,AirTC,IEEE4,0)
Sample(1,RH,IEEE4)
EndTable
BeginProg
Scan(5,Sec,1,0)
'HMP155A Temperature & Relative Humidity Sensor measurements AirTC and RH:
PortSet (9,1)
Delay(0,2,Sec)
VoltSE(AirTC,1,mV2500,2,0,0,_60Hz,.14,-80)
VoltSE(RH,1,mV2500,1,0,0,_60Hz,0.1,0)
PortSet (9,0)
If RH>100 And RH<108 Then RH=100
CallTable(Temp_RH)
NextScan
EndProg
7.4.2 CR10(X) Program Using Single-Ended Measurement Instructions
Using SW12V on Datalogger
;Turn the HMP155A on.
;
01: Do (P86)
1: 41
Set Port 1 High
;Jumper wire from SW12V control to C1
;Green wire (C1) if using SW12V Power Switch
;For CR23X or CR5000 use 49 for SW12V internal
;control port
;Pause 2 seconds before making measurements so the
;probe can stabilize on true readings.
;
02: Excitation with Delay (P22)
1: 1
Ex Channel
2: 0
Delay W/Ex (units = 0.01 sec)
3: 500
Delay After Ex (units = 0.01 sec)
4: 0
mV Excitation
;Measure the HMP155A temperature.
;
03: Volt (SE) (P1)
1: 1
Reps
2: 5
2500 mV Slow Range
3:
4:
5:
6:
3
1
.14
-80
SE Channel
Loc [ T_C
Mult
Offset
;CR510, CR500 (2500mv); CR23X (1000 mV);
21X, CR7 (5000 mV)
;Yellow wire (SE 3), white or purple wire (AG)
]
;See TABLE 7-4 for alternative multipliers
;See TABLE 7-4 for alternative offsets
15
Model HMP155A Temperature and Relative Humidity Probe
;Measure the HMP155A relative humidity.
;
04: Volt (SE) (P1)
1: 1
Reps
2: 5
2500 mV Slow Range
3:
4:
5:
6:
4
2
.1
0
SE Channel
Loc [ RH_pct ]
Mult
Offset
;See TABLE 7-5 for alternative multipliers
;Turn the HMP155A off.
;
05: Do (P86)
1: 51
Set Port 1 Low
7.5
;CR510, CR500 (2500 mV); CR23X (1000 mV);
21X, CR7 (5000 mV)
;Blue wire (SE 4), white or purple wire (AG)
;Jumper wire from SW12V control to C1
;Orange wire (C1) if older wiring
;Green wire (C1) if using SW12V device
;For CR23X or CR5000 use 59 for SW12V internal
;control port
Long Lead Lengths
This section describes the error associated with measuring the HMP155A with
a single-ended measurement if the probe has a long cable. To avoid these
problems, Campbell Scientific recommends measuring the HMP155A using a
differential analog measurement (Instruction 2) when long lead lengths are
required. Generic datalogger connections for measuring the HMP155A using a
differential measurement are given in TABLE 7-2.
Understanding the details in this section is not required for the general
operation of the HMP155A with Campbell Scientific’s dataloggers.
The signal reference (white) and the power ground (black) are in common
inside the HMP155A. When the HMP155A temperature and relative humidity
are measured using a single-ended analog measurement, both the signal
reference and the power ground are connected to ground at the datalogger. The
signal reference and the power ground both serve as the return path for 12 V.
There will be a voltage drop along those leads because the wire itself has
resistance. The HMP155A draws approximately 4 mA when it is powered.
The wire used in the HMP155A (pn 9721) has resistance of 27.7 Ω/1000 feet.
Since the signal reference and the power ground are both connected to ground
at the datalogger, the effective resistance of those wires together is half of 27.7
Ω/1000 feet, or 13.9 Ω/1000 feet. Using Ohm’s law, the voltage drop (Vd),
along the signal reference/power ground, is given by Eq. (1).
Vd
= I ∗R
= 4 mA ∗ 13.9 Ω 1000 ft
(1)
= 55.6 mV 1000 ft
This voltage drop will raise the apparent temperature and relative humidity
because the difference between the signal and the signal reference lead, at the
datalogger, has increased by Vd. The approximate error in temperature and
16
Model HMP155A Temperature and Relative Humidity Probe
relative humidity is 0.56°C and 0.56% per 100 feet of cable length,
respectively.
TABLE 7-7. Wiring for
Differential Measurement Examples
Color
Description
CR1000
CR10(X)
Yellow
Temperature
2H
2H
Jumper to 1L
2L
2L
Blue
Relative Humidity
1H
1H
White
Signal Reference
1L
1L
Jumper from SW12V Control
C1
Red
Power
SW12 V
SW12 V
Black
Power Ground
G
G
Clear
Shield
G
7.5.1 CR1000 Program Using Differential Measurement Instructions Using
SW12V on Datalogger
'CR1000 program to measure HMP155A with differential measurements
Public AirTC
Public RH
DataTable(Temp_RH,True,-1)
DataInterval(0,60,Min,0)
Average(1,AirTC,IEEE4,0)
Sample(1,RH,IEEE4)
EndTable
BeginProg
Scan(5,Sec,1,0)
'HMP155A Temperature & Relative Humidity Sensor measurements AirTC and RH:
PortSet (9,1)
Delay(0,2,Sec)
VoltDiff (AirTC,1,mV2500,2,True,0,_60Hz,.14,-80)
VoltDiff (RH,1,mV2500,1,True,0,_60Hz,0.1,0)
PortSet (9,0)
If RH>100 And RH<108 Then RH=100
CallTable(Temp_RH)
NextScan
EndProg
17
Model HMP155A Temperature and Relative Humidity Probe
7.5.2 CR10(X) Program Using Differential Measurement Instructions
Using SW12V on Datalogger
;Turn the HMP155A on.
;
01: Do (P86)
1: 41
Set Port 1 High
;Jumper wire from SW12V control to C1
;Green wire (C1) if using SW12V device
;For CR23X or CR5000 use 49 for SW12V internal
;control port
;Pause 2 seconds before making measurements so the
;probe can stabilize on true readings.
;
02: Excitation with Delay (P22)
1: 1
Ex Channel
2: 0
Delay W/Ex (units = 0.01 sec)
3: 500
Delay After Ex (units = 0.01 sec)
4: 0
mV Excitation
;Measure the HMP155A temperature.
;
03: Volt (Diff) (P2)
1: 1
Reps
2: 5
2500 mV Slow Range
3:
4:
5:
6:
2
1
.14
-80
DIFF Channel
Loc [ T_C
]
Mult
Offset
;Measure the HMP155A relative humidity.
;
04: Volt (Diff) (P2)
1: 1
Reps
2: 5
2500 mV Slow Range
3:
4:
5:
6:
1
2
.1
0
DIFF Channel
Loc [ RH_pct ]
Mult
Offset
;Turn the HMP155A off.
;
05: Do (P86)
1: 51
Set Port 1 Low
18
;CR510, CR500 (2500mv); CR23X (1000 mV);
21X, CR7 (5000 mV)
;Yellow wire (2H), jumper (2L to 1L)
;See TABLE 7-4 for alternative multipliers
;See TABLE 7-4 for alternative offsets
;CR510, CR500 (2500mv); CR23X (1000 mV);
21X, CR7 (5000 mV)
;Blue wire (1H), white or purple wire (1L)
;See TABLE 7-5 for alternative multipliers
;Jumper wire from SW12V control to C1
;Green wire (C1) if using SW12V device
;For CR23X or CR5000 use 59 for SW12V internal
;control port
Model HMP155A Temperature and Relative Humidity Probe
7.6
Absolute Humidity
The HMP155A measures relative humidity. Relative humidity is defined by
the equation below:
RH =
e
∗ 100
es
(2)
where RH is the relative humidity, e is the vapor pressure in kPa , and es is the
saturation vapor pressure in kPa. The vapor pressure, e, is an absolute measure
of the amount of water vapor in the air and is related to the dewpoint
temperature. The saturation vapor pressure is the maximum amount of water
vapor that air can hold at a given air temperature. The relationship between
dewpoint and vapor pressure, and air temperature and saturation vapor pressure
are given by Goff and Gratch (1946), Lowe (1977), and Weiss (1977).
When the air temperature increases, so does the saturation vapor pressure.
Conversely, a decrease in air temperature causes a corresponding decrease in
saturation vapor pressure. It follows then from Eq. (2) that a change in air
temperature will change the relative humidity, without causing a change
absolute humidity.
For example, for an air temperature of 20°C and a vapor pressure of 1.17 kPa,
the saturation vapor pressure is 2.34 kPa and the relative humidity is 50%. If
the air temperature is increased by 5°C and no moisture is added or removed
from the air, the saturation vapor pressure increases to 3.17 kPa and the relative
humidity decreases to 36.9%. After the increase in air temperature, the air can
hold more water vapor. However, the actual amount of water vapor in the air
has not changed. Thus, the amount of water vapor in the air, relative to
saturation, has decreased.
Because of the inverse relationship between relative humidity and air
temperature, finding the mean relative humidity is meaningless. A more useful
quantity is the mean vapor pressure. The mean vapor pressure can be
computed online by the datalogger as shown in the following examples.
TABLE 7-8. Wiring for Vapor Pressure Examples
Color
Description
CR1000
CR10(X)
Yellow
Temperature
SE 2 (1L)
SE 3 (2H)
Blue
Relative Humidity
SE 1 (1H)
SE 4 (2L)
White
Signal Reference
AG
Jumper from
SW12V Control
C1
Red
Power
SW12V
SW12 V
Black
Power Ground
AG
Clear
Shield
G
19
Model HMP155A Temperature and Relative Humidity Probe
7.6.1 CR1000 Program that Computes Vapor Pressure and Saturation
Vapor Pressure
'CR1000 program that calculates Vapor Pressure
Public AirTC
Public RH
Public RH_Frac, e_Sat, e_kPa
DataTable(Temp_RH,True,-1)
DataInterval(0,60,Min,0)
Average(1,AirTC,IEEE4,0)
Sample(1,RH,IEEE4)
Sample(1,e_kPa,IEEE4)
EndTable
BeginProg
Scan(5,Sec,1,0)
'HMP155A Temperature & Relative Humidity Sensor measurements AirTC and RH:
PortSet (9,1)
Delay(0,2,Sec)
VoltSE(AirTC,1,mV2500,2,0,0,_60Hz,.14,-80)
VoltSE(RH,1,mV2500,1,0,0,_60Hz,0.1,0)
PortSet (9,0)
If RH>100 And RH<108 Then RH=100
'Calculate Vapor Pressure
'Convert RH percent to RH Fraction
RH_Frac = RH * 0.01
'Calculate Saturation Vapor Pressure
SatVP(e_Sat, AirTC)
'Compute Vapor Pressure, RH must be a fraction
e_kPa = e_Sat * RH_Frac
CallTable(Temp_RH)
NextScan
EndProg
7.6.2 CR10(X) Program that Computes Vapor Pressure and Saturation
Vapor Pressure
;Turn the HMP155A on.
;
01: Do (P86)
1: 41
Set Port 1 High
;Jumper wire from SW12V control to C1
;Green wire (C1) if using SW12V device
;For CR23X or CR5000 use 49 for SW12V internal
;control port
;Pause 5 seconds before making measurements so the
;probe can stabilize on true readings.
;
02: Excitation with Delay (P22)
1: 1
Ex Channel
2: 0
Delay W/Ex (units = 0.01 sec)
3: 500
Delay After Ex (units = 0.01 sec)
4: 0
mV Excitation
20
Model HMP155A Temperature and Relative Humidity Probe
;Measure the HMP155A temperature.
;
03: Volt (SE) (P1)
1: 1
Reps
2: 5
2500 mV Slow Range
3:
4:
5:
6:
3
1
.14
-80
SE Channel
Loc [ T_C
Mult
Offset
;CR510, CR500 (2500mv); CR23X (1000 mV);
21X, CR7 (5000 mV)
;Yellow wire (SE 3), white or purple wire (AG)
]
;Measure the HMP155A relative humidity.
;
04: Volt (SE) (P1)
1: 1
Reps
2: 5
2500 mV Slow Range
3:
4:
5:
6:
4
2
.001
0
;CR510, CR500 (2500mv); CR23X (1000 mV);
21X, CR7 (5000 mV)
;Blue wire (SE 4), white or purple wire (AG)
SE Channel
Loc [ RH_frac ]
Mult
Offset
;Turn the HMP155A off.
;
05: Do (P86)
1: 51
Set Port 1 Low
;Compute the saturation vapor pressure.
;The temperature must be in degrees Celsius.
;
06: Saturation Vapor Pressure (P56)
1: 1
Temperature Loc [ T_C
2: 3
Loc [ e_sat ]
;Jumper wire from SW12V control to C1
;Green wire (C1) if using SW12V device
;For CR23X or CR5000 use 59 for SW12V internal
;control port
]
;Compute the vapor pressure.
;Relative humidity must be a fraction.
;
07: Z=X*Y (P36)
1:
3 X Loc [ e_sat ]
2:
2 Y Loc [ RH_frac ]
3:
4 Z Loc [ e
]
8.
Sensor Maintenance
The HMP155A Probe requires minimal maintenance. Check monthly to make
sure the radiation shield is free from debris. The filter at the end of the sensor
should also be checked for contaminates.
21
Model HMP155A Temperature and Relative Humidity Probe
8.1
Periodic Maintenance
8.1.1 Cleaning
Clean the probe with a soft, lint-free cloth moistened with mild detergent.
8.1.2 Changing the Probe Filter
1.
Remove the filter from the probe.
2.
After removing the filter, check the O-ring and change it if necessary.
3.
Install a new filter on the probe.
New filters can be ordered from Campbell Scientific or Vaisala.
FIGURE 8-1. Changing the filter
The following numbers refer to FIGURE 8-1 above:
1=Filter
2=O-ring
3=HUMICAP® sensor
4 Pt100 temperature sensor
22
Model HMP155A Temperature and Relative Humidity Probe
When installed in close proximity to the ocean or other bodies of salt water, a
coating of salt (mostly NaCl) may build up on the radiation shield, sensor, filter
and even the chip. NaCl has an affinity for water. The humidity over a
saturated NaCl solution is 75%. A buildup of salt on the filter or chip will
delay or destroy the response to atmospheric humidity.
The filter can be rinsed gently in distilled water. If necessary, the chip can be
removed and rinsed as well. Do not scratch the chip while cleaning.
Long term exposure of the HUMICAP® relative humidity sensor to certain
chemicals and gases may affect the characteristics of the sensor and shorten its
life. TABLE 8-1 lists the maximum ambient concentrations, of some
chemicals, that the HUMICAP® can be exposed to.
TABLE 8-1. Chemical Tolerances of HMP155A
Chemical
Concentration (PPM)
Organic solvents
1000 to 10,000
Aggressive chemicals
(e.g., SO2, H2SO4, H2S,
HCl, Cl2, etc.)
1 to 10
Weak Acids
100 to 1000
Bases
10,000 to 100,000
Recalibrate the HMP155A annually. Obtain an RMA number before returning
the HMP155A to Campbell Scientific for recalibration.
9.
Troubleshooting
Symptom: -9999, NAN, ─80°C, or 0 % relative humidity
1.
Check that the sensor is wired to the correct input channels as specified by
the measurement instructions.
2.
Verify the range code is correct for the datalogger type.
3.
Verify the red power wire is correctly wired to the 12V, Switched 12V, or
SW12V Power Switch. The terminal the wire is connected to will depend
on the datalogger program.
Connect the red wire to a 12V terminal to constantly power the sensor for
troubleshooting purposes. With the red wire connected to12V, a
voltmeter can be used to check the output voltage for temperature and
relative humidity on the yellow and blue wires respectively (temperature
°C = mV * 0.14 – 80.0; relative humidity % = mV * 0.1).
Symptom: Incorrect temperature or relative humidity
1.
Verify the multiplier and offset parameters are correct for the desired units
(TABLE 7-4 and TABLE 7-5).
23
Model HMP155A Temperature and Relative Humidity Probe
10. References
AASC, 1985: The State Climatologist (1985) Publication of the American
Association of State Climatologists: Heights and Exposure Standards for
Sensors on Automated Weather Stations, v. 9, No. 4 October, 1985.
(www.stateclimate.org/publications/state-climatologist/NOAA-NCYSCBOOKS-SC77097/00000029.pdf)
EPA, 2008: Quality Assurance Handbook for Air Pollution Measurement
Systems, Vol. IV, Meteorological Measurements, Ver. 2.0, EPA-454/B-08002 (revised 2008). Office of Air Quality Planning and Standards,
Research Triangle Park, NC 27711.
Goff, J. A. and S. Gratch, 1946: Low-pressure properties of water from -160°
to 212°F, Trans. Amer. Soc. Heat. Vent. Eng., 51, 125-164.
Lowe, P. R., 1977: An approximating polynomial for the computation of
saturation vapor pressure, J. Appl. Meteor., 16, 100-103.
Meyer, S. J. and K. G. Hubbard, 1992: Nonfederal Automated Weather
Stations and Networks in the United States and Canada: A Preliminary
Survey, Bulletin Am. Meteor. Soc., 73, No. 4, 449-457.
Vaisala, Inc. (2008) HMP155A Humidity and Temperature Probe User Guide,
Helsinki, Finland. Text and figures used with permission of Vaisala, Inc.
Weiss, A., 1977: Algorithms for the calculation of moist air properties on a
hand calculator, Amer. Soc. Ag. Eng., 20, 1133-1136.
WMO, 2008. Guide to Meteorological Instruments and Methods of
Observation. World Meteorological Organization No. 8, 7th edition,
Geneva, Switzerland.
24
Appendix A. Interfacing with HMP155A
RS485 Output
A.1 RS485 Interface Options
The HMP155A outputs a 0 to 1 Vdc signal for temperature and relative
humidity that can be measured by all models of Campbell Scientific
dataloggers with model HMP155ACBL1 cable. The HMP155A also has
RS485 outputs for temperature and relative humidity that can be interfaced to
the CR800, CR1000, and CR3000 dataloggers with model HMP155ACBL2
cable and the SDM-SIO1 Serial I/O Module. Vaisala also sells a cable with
RS485 outputs which is documented in the example programs below.
The MD485 Multidrop Interface can also be used to interface the RS485
outputs to the CR800, CR1000, and CR3000 dataloggers. This option requires
a USB to RS485 cable (available from Vaisala) to change the default baud rate
of the RS485 output from the default of 4800 to a baud rate supported by the
MD485.
A.2 SDM-SIO1 Serial I/O Module Interface Option
The SDM-SIO1 module is used to interface the RS485 outputs of the
HMP155A to the datalogger. The SDM-SIO1 functions like a built-in serial
port to the datalogger. Data are buffered in the SDM-SIO1 and retrieved by the
datalogger using standard program instructions.
The SDM-SIO1 connects to the datalogger’s 12V, G, and SDM terminals (C1,
C2, C3). Sensor wiring to the SDM-SIO1 and the datalogger is documented in
the example program below.
A-1
Appendix A. Interfacing with HMP155A RS485 Output
A.2.1 Program Example for SDM-SIO1 Module
The following program sends the commands ‘SMODE RUN’ and ‘R’ to enable
the RS485 output. SerialInRecord and Mid instructions parse the serial string
and put the temperature and relative humidity values into public variables.
'CR1000 Series Datalogger
'Sensor Wiring:
'HMP155A with RS485 Output:
'
' HMP155A
HMP155A
' CSI
Vaisala
' *Cable
Cable
'
'
'
'
'
'
'
blue
yellow
black
red
white
shield (clear)
SDM-SIO1
pink
Y
brown
Z
red
blue
green
0V
black
grey, pink, brown - NOT used
CR1000
Connector Pin-Out
G
12V
6
2
8
7
3
not connected
Ground
' *HMP155ACBL2 cable, ordered separately
'Declare Public Variables
Public TempC, RH, NBytesReturned
Public SerialIndest As String * 26
Public String_1 As String
Public String_2 As String
Const SensorPort=32
Const CRLF=CHR(13)+CHR(10)
SequentialMode
'Define Data Tables
DataTable (Table1,1,-1)
DataInterval (0,15,Min,10)
Average (1,TempC,FP2,False)
Sample (1,RH,FP2)
EndTable
'Main Program (for sensor configured for default settings of 4800 baud, E,7,1)
BeginProg
SerialOpen (SensorPort,4800,58,0,53)
'Strings to start serial output
String_1 = "SMODE RUN"+CRLF
String_2 = "R"+CRLF
' buffer = 2*number of bytes + 1
' SDM-SI01 port 58 for half duplex,7,E,1
' set SMODE to "RUN"
' send "R" to start serial output
'Instructions to enable RS485 serial output
SerialOut (SensorPort,String_1,"RUN",3,100)
Delay (0,500,mSec)
SerialOut (SensorPort,String_2,"RH",3,100)
'send String_1, wait for 'RUN' response
'send String_2
Scan (5,Sec,0,0)
'Get serial string from sensor
SerialInRecord (SensorPort,SerialIndest,00,24,&H0D0A,NBytesReturned,00)
'Parse RH and temp from string
RH=Mid (SerialIndest,5,4)
SplitStr (RHArray(1),SerialIndest,"=",2,0)
A-2
'&H0D0A = CRLF
Appendix A. Interfacing with HMP155A RS485 Output
CallTable Table1
NextScan
EndProg
The public variables for temperature and relative humidity can be viewed in the
‘Numeric Display’ mode as shown below.
For troubleshooting purposes, the serial data buffer in the datalogger can be
viewed using the ‘W’ terminal command. This is done by connecting to the
datalogger from the ‘Connect’ button of Loggernet or PC400W. From the
Connect screen, select Tools|Terminal Emulator. Click the ‘Open Terminal’
button, and hit the enter key to get the ‘CR1000’ prompt. Type ‘W’ for the
‘Serial Comms Sniffer’. Enter 32 for for the SDM-SIO1, and ‘Y’ for ASCII.
Raw serial data received by the buffer is displayed on the screen as shown
below.
A-3
Appendix A. Interfacing with HMP155A RS485 Output
A.3 MD485 Multidrop Interface Option
The MD485 Multidrop Interface can be used to interface the RS485 outputs of
the HMP155A to the datalogger’s CS I/O port. Connect the MD485’s CS I/O
port to the datalogger’s CS I/O port with an SC12 cable. Sensor wiring to the
MD485 and the datalogger is documented in the example program below.
The HMP155A has a default RS485 baud rate of 4800, which must be changed
to 9600 to be compatible with the MD485. To change settings in the
HMP155A, Vaisala’s USB to RS485 cable is required to interface the
HMP155A sensor to a computer. Commands to change settings are sent to the
HMP155A using a terminal emulator such as Windows HyperTerm.
Vaisala’s USB to RS485 cable includes a CD with drivers that must be
installed on the computer before the cable can be used. Insert the CD into the
computer’s CD drive and follow the prompts.
A-4
Appendix A. Interfacing with HMP155A RS485 Output
Use the Device Manager in Windows to determine which COM port the
USB/RS485 cable was assigned:
A-5
Appendix A. Interfacing with HMP155A RS485 Output
Configure Windows HyperTerminal for the appropriate COM port (for
example, COM8 in the example above) for the default HMP155A RS485
settings of 4800 baud, 7, E, 1.
Using HyperTerminal, send the following commands to the HMP155A:
VERS[enter] to get a response from the sensor; for example, HMP155A 1.26
SERI[enter] to get the current RS485 settings; for example, 4800 E 7 1
SERI 9600 N 8 1[enter] to change the RS485 settings; response should be 9600
N81
R[enter] to put the sensor in the Run mode to output continuous measurements
Responses to the commands are shown in the screen capture below.
A-6
Appendix A. Interfacing with HMP155A RS485 Output
After the settings have been changed, change the baud rate in HyperTerminal
to 9600, and make sure the relative humidity and temperature string is being
displayed before connecting the sensor to the MD485.
A-7
Appendix A. Interfacing with HMP155A RS485 Output
A.3.1 MD485 Multidrop Interface Configuration
Using the Device Configuration Utility, configure the MD485 as shown below.
Connect the MD485’s CS I/O port to the datalogger’s CS I/O port using an
SC12 cable. Use the HMP155ACBL2 to connect the HMP155A sensor to the
MD485 and the datalogger (CR1000, CR800, or CR3000) as shown in the
following table. The table also shows wiring for cables purchased from
Vaisala.
HMP155A
CSI Cable
HMP155A
Vaisala
Cable
MD485
Blue
Pink
B
6
Yellow
Brown
A
2
Black
Red
G
8
Red
Blue
12V
7
White
Green
Ground
3
Shield (clear)
Black
Ground
Not
Connected
Grey, Pink,
Brown NOT used
A-8
CR1000
Connector
Pin-Out
Appendix A. Interfacing with HMP155A RS485 Output
A.3.2 CR1000 Example Program for use with MD485
The following program sends the commands ‘SMODE RUN’ and ‘R’ to enable
the RS485 output. SerialInRecord and Mid instructions parse the serial string
and put the temperature and relative humidity values into public variables.
'CR1000 Series Datalogger
'Change HMP155A default serial settings from 4800,E,7,1 To 9600,N,8,1:
' Sensor Wiring:
' *CSI cable
Vaisala cable
'
'
'
'
'
'
'
pink
B
brown
A
red
blue
green
Ground
Black
grey, pink, brown - NOT used
blue
yellow
black
red
white
shield (clear)
MD485
CR1000
Connector Pin-Out
G
12V
6
2
8
7
3
not connected
Ground
'MD485 settings:
' CS I/O AND RS-485
' SDC Address 7
' Transparent Communication
' RS485 baud 9600
' *HMP155ACBL2, ordered separately
'Connect CS I/O port of MD485 to CS I/O port on CR1000 with SC12 cable.
Public NBytesReturned As Long
Public SerialIndest As String * 26
Public RHArray(2) As String
Alias RHArray(1)=RH
Alias RHArray(2)=TempC
Public String_1 As String
Public String_2 As String
Const SensorPort=32
Const CRLF=CHR(13)+CHR(10)
SequentialMode
'Define Data Tables
DataTable (Table1,1,-1)
DataInterval (0,15,Min,10)
Average (1,TempC,FP2,False)
Sample (1,RH,FP2)
EndTable
'Main Program (for sensor configured for default settings of 4800 baud, E,7,1)
BeginProg
SerialOpen (SensorPort,4800,58,0,53) ' buffer = 2*number of bytes + 1
' SDM-SI01 port 58 for half duplex,7,E,1
'Strings to start serial output
String_1 = "SMODE RUN"+CRLF ' set SMODE to "RUN"
String_2 = "R"+CRLF ' send "R" to start serial output
'Instructions to enable RS485 serial output
SerialOut (SensorPort,String_1,"RUN",3,100) 'send String_1, wait for 'RUN' response
Delay (0,500,mSec)
SerialOut (SensorPort,String_2,"RH",3,100) 'send String_2
Scan (5,Sec,0,0)
'Get serial string from sensor
SerialInRecord (SensorPort,SerialIndest,00,24,&H0D0A,NBytesReturned,00) '&H0D0A = CRLF
A-9
Appendix A. Interfacing with HMP155A RS485 Output
'Parse RH and temp from string
SplitStr (RHArray(1),SerialIndest,"=",2,0)
CallTable Table1
NextScan
EndProg
The public variables for temperature and relative humidity can be viewed in the
‘Numeric Display’ mode as shown below.
For troubleshooting purposes, the serial data buffer in the datalogger can be
viewed using the ‘W’ terminal command. This is done by connecting to the
datalogger from the ‘Connect’ button of Loggernet or PC400W. From the
Connect screen, select Tools|Terminal Emulator. Click the ‘Open Terminal’
button, and hit the enter key to get the ‘CR1000’ prompt. Type ‘W’ for the
‘Serial Comms Sniffer’. Select ‘4’ for ‘ComSDC7’, and ‘Y’ for ASCII. Raw
serial data received by the buffer is displayed on the screen as shown below.
A-10
Appendix A. Interfacing with HMP155A RS485 Output
A-11
Appendix A. Interfacing with HMP155A RS485 Output
A-12
Campbell Scientific Companies
Campbell Scientific, Inc. (CSI)
815 West 1800 North
Logan, Utah 84321
UNITED STATES
www.campbellsci.com • [email protected]
Campbell Scientific Africa Pty. Ltd. (CSAf)
PO Box 2450
Somerset West 7129
SOUTH AFRICA
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PO Box 8108
Garbutt Post Shop QLD 4814
AUSTRALIA
www.campbellsci.com.au • [email protected]
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Rua Apinagés, nbr. 2018 ─ Perdizes
CEP: 01258-00 ─ São Paulo ─ SP
BRASIL
www.campbellsci.com.br • [email protected]
Campbell Scientific Canada Corp. (CSC)
11564 - 149th Street NW
Edmonton, Alberta T5M 1W7
CANADA
www.campbellsci.ca • [email protected]
Campbell Scientific Centro Caribe S.A. (CSCC)
300 N Cementerio, Edificio Breller
Santo Domingo, Heredia 40305
COSTA RICA
www.campbellsci.cc • [email protected]
Campbell Scientific Ltd. (CSL)
Campbell Park
80 Hathern Road
Shepshed, Loughborough LE12 9GX
UNITED KINGDOM
www.campbellsci.co.uk • [email protected]
Campbell Scientific Ltd. (CSL France)
3 Avenue de la Division Leclerc
92160 ANTONY
FRANCE
www.campbellsci.fr • [email protected]
Campbell Scientific Ltd. (CSL Germany)
Fahrenheitstraße 13
28359 Bremen
GERMANY
www.campbellsci.de • [email protected]
Campbell Scientific Spain, S. L. (CSL Spain)
Avda. Pompeu Fabra 7-9, local 1
08024 Barcelona
SPAIN
www.campbellsci.es • [email protected]
Please visit www.campbellsci.com to obtain contact information for your local US or international representative.
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