Humidity Dew point meter.

635-1 Hygrometer Air Humidity Temperature Dew Point.
testo 635-1, humidity/temperature measuring instrument, with battery.
The instrument for measuring air moisture, material equilibrium moisture and pressure dewpoint in compressed air systems. Up to 3 temperature or humidity probes can be displayed; data transmission is radio-controlled, i.e. wireless. Measurement data can be transmitted by infrared to the printer.

635-1 Hygrometer

Model  Description 
0560 6351  635-1 Compact Pro Thermohygrometer
0563 6352  635-2 Compact Pro Hygrometer w/memory and software

It is also possible, during cyclical printing, to print measurement data once every minute, for example.
Model 635 immediately displays the dewpoint difference between ambient air and the wall surface when
analyzing moisture on walls and ceilings. There are precision probes up to -60°C tpd available to inspect
pressure dewpoint in compressed air systems. The humidity sensor developed by Testo has proven itself world-wide and has outstanding features in terms of precision, long-term stability, temperature resistance and robustness.

Storage temperature  -30 to +70 °C 
Operating temperature  -20 to +50 °C 
Probe type Typ T (Cu-CuNi)   
Meas. range  -200 to +400 °C 
Accuracy  ±0.3 °C (-60 to +60 °C)
±0.5% of mv (remaining range) 
Resolution  0.1 °C 
Probe type Type K   
Meas. Range  -200 to +1370 °C  
Accuracy  ±0.3 °C (-60 to +60 °C)
±0.5% of mv (remaining range) 
Resolution  0.1 °C 
Probe Type NTC    
Meas. Range  -40 to +150 °C 
Accuracy  ±0.2 °C (-25 to +74.9 °C)
±0.4 °C (-40 to -25.1 °C)
±0.4 °C (+75 to +99.9 °C)
±0.5% of mv (remaining range) C 
Resolution   0.1 °C 
Probe type Absolute pressure probe   
Meas. Range  0 to +2000 hPa 
Resolution  0.1 hPa 
Probe type humid. sensor, cap.   
Meas. Range  0 to +100 %RH 
Resolution  0.1 %RH