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Vaisala HMI41, HMP46 Indicator and High Temperature Probe

Indicator and High Temperature Probe
HMI41, HMP46

The Vaisala HUMICAP® Humidity
Indicator HMI41 fitted with the Vaisala HUMICAP® Humidity and Temperature Probe HMP46 can be used for spot checking humidity and temperature in ducts or chambers. Typical applications are plant maintenance, installation and inspection of air conditioning systems, production and storage areas and production processes. In addition, it is suitable for field checking Vaisala's humidity transmitters. 

Withstands high temperatures
The HMP46 operates in full humidity range of 0 ... 100 %RH. The temperature range is from-40 to +100 °C (-40 ... +212 °F). For short periods of time, the probe can withstand temperatures up to+180 °C (+356 °F). The HMP46 probe is solid and rugged. Its stainless steel probe is made to withstand rough handling in mechanically demanding applications. The probe’s long shaft can also reach otherwise unreachable places.

Versatile and easy to use
In addition to displaying the humidity and temperature readings, the HMI41 indicator calculates dew point and wet bulb temperature, absolute humidity and mixing ratio. 

The indicator has an easy-to-read two line liquid crystal display. The display units (metric or non-metric) are easily selected. 

These features, plus fast response time, high measurement accuracy and excellent stability, as well as the wide temperature range of the probe, make the HMI41/HMP46 combination an ideal choice for the most demanding applications.

High performance sensor
The HMP46 probe incorporates Vaisala HUMICAP® Sensor. This sensor has high accuracy, excellent long-term stability and negligible hysteresis. In addition, the sensor is insensitive to dust, particulate dirt and most chemicals.

▪ RH measurement range 0 ... 100 %RH
▪ Temperature measurement range -40 ...  +100 °C  (-40 ... +212 °F), for short periods up to +180 °C  (+356 °F)
▪ Calculates dew point, wet bulb temperature, absolute humidity and mixing ratio
▪ Versatile and easy-to-use
▪ Incorporates Vaisala HUMICAP® Sensor
▪ Excellent stability
▪ Data collection with serial line
▪ NIST traceable (certificate included)
▪ Optional carrying case and calibration cable
▪ Available as a complete calibration kit HMK41

HMI41 indicator
Calculated variables dew point temperature, absolute humidity, wet bulb temperature, mixing ratio
Resolution 0.1 %RH; 0.1 °C/°F
Power supply 4 batteries, type AA (LR 6)
Battery operation time (alkaline batteries) 72 h continuous use
Auto-off function
Operating temperature -20 ... +60 °C (-4 ... +140 °F)
Storage temperature -40 ... +70 °C (-40 ... +158 °F)
Display two line LCD
Housing material ABS plastic
Housing classification IP53 (with connectors blocked)
Weight (incl. batteries) 300 g
Maximum measurement error of indicator at +20 °C
humidity ±0.1 %RH
temperature ±0.1 °C (±0.18 °F)
HMP46 probe
Measurement range 0 ... 100 %RH, non-condensing
Accuracy (incl. nonlinearity, hysteresis and repeatability) at +20 °C
Maximum achievable accuracy when calibrated against high quality, certified humidity standards 0 ... 90 %RH : ±1 %RH
90 ... 100 %RH : ±2 %RH
When calibrated against salt solutions (ASTM E104-85) 0 ... 90 %RH : ±2 %RH
90 ... 100 %RH : ±3 %RH
Typical long-term stability better than 1 %RH per year
Response time (90%)
at +20 °C in still air w/sintered filter
15 s
Humidity sensor HUMICAP® 180
Continuous measurement 40 ... +100 °C (-40 ... +212 °F)
Short-term measurement -40 ... +180 °C (-40 ... +356 °F)
Accuracy at +20 °C (+68 °F) ±0.2 °C (±0.36 °F)
Temperature sensor Pt 100 IEC 751 1/3 class B
Typical ranges of calculated variables dew point temperature : -20 ... +100 °C (-4 ... +100 °F)
absolute humidity : 0 ... 600 g/m3
wet bulb temperature : 0 ... 100 °C (32 ... 212 °F)
mixing ratio : 0 ... 600 g/kg d.a.
The accuracies of these calculated variables are limited by the accuracies of the measured variables on which they are based, namely RH and T. The RH and T accuracies are stated under HMP46 probe.
Cable length 1500 mm; extended spiral cable
Operating temperature range
for electronics
-20 ... +60 °C (-4 ... +140 °F)
Housing material Electronics housing ABS plastic
Probe stainless steel
Housing classification
IP65 (NEMA 4)
Sensor protection IP65 (NEMA 4)
Sensor protection sintered filter, part no. 0195
option membrane filter, part no. 10159HM (max +80 °C / +176 °F) plastic grid, part no. 6221 (max +80 °C / +176 °F)
Weight 450 g
Electromagnetic compatibility Complies with EMC standard
EN61326-1, Portable Equipment

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