GMP251 Carbon Dioxide Probe
For %-level measurements
Features
• Measurement range 0 … 20 %CO2
• Intelligent, standalone probe with analog and digital outputs
• Compatible with Indigo transmitters and Insight PC software
• Wide operating temperature range (−40 … +60 °C)
• IP65-classified housing
• Integrated temperature measurement for CO2 compensation purposes
• Compensations also for pressure, oxygen, and humidity
• Sensor head heated to prevent condensation
Vaisala CARBOCAPâ Carbon Dioxide Probe GMP251 is a new intelligent probe for measuring carbon dioxide. This robust, standalone measurement device is designed for use in demanding applications, such as life science incubators, where stable, reliable, and accurate performance is required.
Benefits
•Superior long-term stability
•Reliable and accurate
•Calibration certificate included
GMP251 is based on Vaisala’s patented, latest-generation CARBOCAP technology that enables exceptional stability. A new type of infrared (IR) light source is used instead of the traditional incandescent light bulb, which extends the lifetime of GMP251.
GMP251 incorporates an internal temperature sensor for compensation of the CO2 measurement according to ambient temperature. The effects of pressure and background gas can also be compensated for. The measurement range is 0 ... 20 %CO2 and the sensor performance is optimized at 5 %CO2 measurement.
The operating temperature range of the probe is wide (−40 … +60 °C
(−40 ... +140 °F)), and the probe housing is classified as IP65. Condensation is prevented as the internal sensor head is heated. GMP251 is resistant to dust and most chemicals, such as H2O2 and alcohol-based cleaning agents.
Ease of use
GMP251 is a compact probe with easy and fast plug-in, plug-out installation. The surface of the probe is smooth, which makes it easy to clean. The probe provides several output options, including analog current and voltage outputs and digital RS-485 output with Modbusâ protocol.
GMP251 can be connected to Indigo series transmitters for an extended range of output and configuration options. See www.vaisala.com/indigo.
For easy-to-use access to field calibration, device analytics, and configuration functionality, the probe can be connected to Vaisala Insight PC software. See www.vaisala.com/insight.
Applications
GMP251 is ideal for life science incubators, cold storages, fruit and vegetable transportation, and for all demanding applications where stable and accurate %-level CO2 measurements are needed.
A flow-through adapter with gas ports is available as an accessory, enabling tubing for easy and flexible remote measurement with a separate pump. A multiplexer can also be added for sampling gas from several locations. 1)
1)Third-party pump and multiplexer not provided by Vaisala.
Technical data
Measurement performance
Measurement range |
0 ... 20 %CO2 |
Accuracy 1) |
|
At 5 %CO2 |
±0.1 %CO2 |
At 0 ... 8 %CO2 |
±0.2 %CO2 |
At 8 ... 20 %CO2 |
±0.4 %CO2 |
Calibration uncertainty |
|
At 5 %CO2 |
±0.07 %CO2 |
At 20 %CO2 |
±0.27 %CO2 |
Long-term stability |
|
|
|
At 0 ... 8 %CO2 |
±0.3 %CO2/year |
At 8 ... 12 %CO2 |
±0.5 %CO2/year |
at 12 ... 20 %CO2 |
±1.0 %CO2/year |
Temperature dependence |
|
|
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With compensation at 5 %CO2, |
< ±0.05 %CO2 |
0 ... +50 °C (+32 ... +122 °F) |
|
With compensation, |
±0.045 % of reading/°C |
0 … 20 %CO2,−40 … +60 °C |
|
(−40 ... +140 °F) |
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|
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without temperature compensation at |
-0.25 % of reading/°C |
5 %CO2 (typical) |
|
Pressure dependence |
|
|
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With compensation at 5 %CO2 |
±0.05 %CO2 |
700 ... 1100 hPa |
|
With compensation, 0 … 20 %CO2 |
±0.015 % of reading/hPa |
500 ... 1200 hPa |
|
|
|
Without compensation (typical) |
+0.15 % of reading/hPa |
Humidity dependence |
|
|
|
With compensation, 0 … 20 %CO2, |
±0.7 % of reading (at +25 °C (+77 °F)) |
0 … 100 %RH |
|
Without compensation (typical) |
+0.05 % of reading / %RH |
|
|
O2 dependence |
|
With compensation, 0 … 20 %CO2, |
±0.6 % of reading (at +25 °C (+77 °F)) |
0 ... 90 %O2 |
|
Without compensation (typical) |
-0.08 % of reading / %O2 |
Start-up, warm-up, and response time |
|
|
|
Start-up time at +25 °C (+77 °F) |
< 10 s |
Warm-up time for full spec. |
< 4 min |
|
|
Response time (T90): |
|
With standard filter |
< 1 min |
|
|
Flow-through option with > 0.1 l/min |
< 1 min |
With spray shield |
< 2 min |
Flow rate dependence (for flow-through option)
Flow rate dependence: |
|
|
|
< 1 l/min flow |
No effect |
1 … 10 l/min flow |
< 0.6 % of reading/ l/min |
1)At 25 °C (77 °F) and 1013 hPa (incl. repeatability and non-linearity).
Compliance
Compliance marks |
CE, RCM, WEEE |
|
|
EMC compatibility |
IEC / EN / BS EN 61326 1, basic |
|
electromagnetic environment |
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|
Operating environment
Operating temperature of CO2 measurement
Storage temperature
Humidity
Condensation prevention
Chemical tolerance (temporary exposure during cleaning)
Pressure
−40 ... +60 °C (−40 ... +140 °F) 1)
−40 ... +70 °C (−40 ... +158 °F)
0 ... 100 %RH, non-condensing
Sensor head heating, when power on
•H2O2 (2000 ppm, noncondensing)
•Alcohol-based cleaning agents (for example ethanol and IPA)
•Acetone
•Acetic acid
Compensated |
500 ... 1100 hPa |
|
|
Operating |
< 1.5 bar |
Gas flow (for flow-through option) |
|
|
|
Operating range |
< 10 l/min |
Recommended range |
0.1 … 0.8 l/min |
1)Occasional short-term exposure to up to +90 °C (+194 °F) allowed, provided that the probe is fully installed inside the measured condition and power is switched on. Accuracy specification not applicable if used in temperatures above +60 °C (+140 °F).
Mechanical specifications
Weight, probe |
45 g (1.59 oz) |
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Materials |
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Probe housing |
PBT polymer |
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Filter |
PTFE membrane, PBT polymer grid |
Connector |
Nickel plated brass, M12 / 5-pin |
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IP rating, probe body |
IP65 |
Connector |
M12 5-pin male |
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Dimensions |
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Probe diameter |
25 mm (0.98 in) |
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Probe length |
96 mm (3.78 in) |
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|
96 mm, Ø 25 mm
Filter
M12 male connector
12 mm 75 mm 9 mm
GMP251 dimensions