Vaisala DM500 - Manual (Page 34)

User's Guide ______________________________________________________________________
32 __________________________________________________________________ M210205EN-D
External gas tubes
The heating of the external gas tubes shall be taken care by the user.
The external lines shall be heated before letting the sample gas flow in
the lines. This is to avoid condensation problems. To facilitate
external gas line heating control, the relay output on the back plate of
the DMP501 activates when heating is ON. In order to keep the gas
connections warm enough the external gas line should be heated
100ºC above ambient and the connections shall be insulated. The
maximum dewpoint measurable with the heated internal gas sampling
is 35 ºC above the ambient temperature.
NOTE
After switching on the heating option, allow the system to warm up at
least 30 minutes to ensure that no condensation occurs in the gas
tubes.
WARNING
When heater function is activated, don't touch with bare fingers the
hot cap of the sensor chamber. Please use gloves when detaching the
cap.
Optional External Temperature Sensor
The external temperature sensor option is needed for temperature or
relative humidity (%RH) measurements.
Temperature measurement range -40…+80 °C (-40…+176 °F)
Typical accuracy
±0.1 °C (±0.18 °F)
Sensor Pt100 PRT DIN IEC 751 class ¼ B
Cable length 2 m/5 m/10 m
cable length
2 /5 /10meters
Ш 1.3
ш6 Ш 5.5
64
93
Figure 11 Mechanical Dimensions (in mm) for Optional
Temperature Sensor