
The Vaisala Humicap HMP155 humidity and temperature probe provides reliable humidity and temperature measurement. The HMP155 has a new generation Vaisala Humicap®180R sensor that has excellent stability and withstands harsh environments. The probe structure is solid and the sensor is protected with a sintered teflon filter, which gives maximum protection against liquid water, dust, and dirt.
Measuring humidity reliably is challenging in environments where humidity is near saturation. Measurements may be corrupted by fog, mist, rain, and heavy dew. A wet probe may not give an accurate measurement in the ambient air.
This is an environment to which Vaisala has designed a patented, warmed probe for reliable measuring. As the sensor head is warmed continuously, the humidity level inside it stays below the ambient level. Thus, it also reduces the risk of condensation forming on the probe.
The HMP155 is especially designed for use in meteorological applications, such as synoptic and hydrological weather stations, aviation, and road weather.
Technical Specifications
Relative Humidity | |
Measurement range | 0 - 100 %RH |
Accuracy (incl. non-linearity, hysteresis and repeatability) at +15 to +25 °C (+59 to +77 °F) -20 to+40 °C (-4 to 104 °F) -40 to -20 °C (-40 to -4 °F) +40 to +60 °C (+104 to +140 °F) -60 to -40 °C (-76 to -40 °F) Factory calibration uncertainty (+20 °C /+68 °F) | ±1 %RH (0 - 90 %RH) ±1.7 %RH (90 - 100 %RH) ±(1.0 + 0.008 x reading) %RH ±(1.2 + 0.012 x reading) %RH ±(1.2 + 0.012 x reading) %RH ±(1.4 + 0.032 x reading) %RH ±0.6 %RH (0 to 40 %RH)* ±1.0 %RH (40 ... 97 %RH)* |
Response time at +20 °C in still air with a sintered PTFE filter 63% 90% | 20 s 60 s |
Temperature | |
Measurement range | -80 °C to +60 °C (-112 °F to +140 °F) |
Accuracy with voltage output at -80 to +20 °C +20 to +60 °C passive (resistive) output according to IEC 751 1/3 Class B RS485 output -80 to +20 °C +20 to +60 °C | ±(0.226 - 0.0028 x temperature) °C ±(0.055 + 0.0057 x temperature) °C ±(0.1 + 0.00167 x |temperature|)°C ±(0.176 - 0.0028 x temperature) °C ±(0.07 + 0.0025 x temperature) °C |
Temperature sensor | Pt100 RTD Class F0.1 IEC 60751 |
Response time with additional temperature probe in 3 m/s air flow 63% 90% | 20 s 35 s |
General | |
Operating temperature range | -80 °C to +60 °C (-112 °F to +140 °F) |
Storage temperature range | -80 °C to +60 °C (-112 °F to +140 °F) |
Connection | 8-pin male M12 connector |
Connection cables | 3.5, 10, and 30 m |
Cable material | PUR |
Wire size | AWG26 |
Service cables | USB connection cable MI70 connection cable |
Additional T probe cable length | 2 m |
Housing material | PC |
Housing classification | IP66 |
Sensor protection | sintered PTFE optional membrane filter |
Weight (probe) | 86 g |
Dimensions | 267 mm L x 40 mm Ø |
Electromagnetic compatibility | Complies with the EMC standard EN61326-1, Electrical equipment for measurement control and laboratory use - EMC requirement for use in industrial locations |
Inputs and outputs | |
Operating voltage | 7 to 28 VDC Note: minimum operating voltage 12 V with 0 to 5 V output and 16 V with 0 to 10 V output, probe heating, chemical purge or XHEAT. |
Outputs | voltage output (0 - 1 V, 0 - 5 V, 0 - 10 V) resistive Pt100 (4-wire connection) RS485 |
Average current consumption (+15 VDC, load 100 kOhm) 0 to 1 V output 0 to 10 V output RS485 during chemical purge with warmed probe | 3 mA +0.5 mA 4 mA max 110 mA max. 150 mA |
Settling time at power-up voltage output RS485 | 2 s 3s |
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