Fluke 971 [5/5] Change 4

Manual Supplement 971 Users

4 3/19

Change #4, 396, 684

On page 7, following the Cleaning section

add:

Humidity Sensor Reconditioning

If unit is found to be out of specification for

humidity, the sensor could be contaminated by

chemical vapors or offset due to long exposure

in a dry environment. This condition is typical

of polymer type humidity sensors. If

contaminated, the sensor will need to be

baked, and rehydrated.

Bake: >50 °C at <5 % RH for 24 hours

Hydration: 20 °C to 30 °C @ 75 % RH for

48 hours

If offset is only due to a long exposure in a dry

environment, sensor will only need to be

rehydrated.

Hydration: 20 °C to 30 °C @ 75 % RH for

48 hours