GANN 30001430, Руководство по эксплуатации

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Use of the active electrode RF-T 28
Hold the electrode in the air or fasten it at the desired measurement site and start the measuring
process. For particularly precise measurements, especially below the usual room temperature (abt.
20 °C) or if there are substantial temperature diff erences between the electrode or meter and their
surroundings, they should be exposed to the ambient atmosphere for approx. 10 - 15 minutes until
temperature equalization. The sensor adapts itself to the surrounding atmosphere even in the
switched-off condition.
Response time of the air humidity sensor
The response time of the sensor is very short so even gently moving air (generated by a slightly
opened door or a window being not tight) may affect the reading. This is why no absolute standstill
of the value displayed can be achieved unless the sensor is installed in an airtight box.
The response time of the sensor in gently moving air is as follows for ambient temperatures from
20 °C to 25 °C
for 90 % of the humidity difference, approx. 20 seconds,
for 95 % of the humidity difference, approx. 30 seconds.
The adjustment time in still air or at very low air movement can be reduced by moving or turning
the electrode (ventilating the sensor).
Filter cap for electrode RF-T 28
For measurements in dust laden air, at emission of harmful substances or at high air speed, a
sintered filter cap can be fitted after removal of the protection cap with venting slots. For protection
of the sintered filter, fix then the plastic cap again.
If the filter becomes dirty it can be washed in residue-free cleaning liquid and/or blown from inside
outwards with compressed air. With the sintered filter inserted, the response time will be
considerably prolonged.