Changing Sensor - HMM100

HMM100 User Guide
Document code
M211024EN
Revision
E
Language
English
Product
HMM100
Document type
User guide
You can replace the HUMICAP sensor in the HMM100 module with another sensor in the HUMICAP family. Compatibility of the replacement sensor depends on the SW version of the HMM100 module:
  • With modules running SW version 1.3.0 or later, the sensor can be replaced with either HUMICAP 180R or HUMICAP 180V.
  • With HMM100 modules running an older SW version, you can replace the sensor only with the same type of sensor as the original.

To check the SW version of the module, issue the VERS serial command. See Show Firmware Version.

You can identify different sensor types by the code printed on the sensor.

Sensor Type Identifying Code Example Notes
HUMICAP 180R R
HUMICAP 180V C
HUMICAP R2 R2

The HUMICAP R2 sensor (delivered with HMM100 modules in 2018) is no longer available as a replacement option. Use HUMICAP 180R as the replacement sensor for HMM100 modules originally delivered with the HUMICAP R2 sensor.
Replacing the sensor is repair maintenance, and it is not necessary in normal operation. If the accuracy of the module does not seem to be within specification, it is more likely that the module is in need of calibration and adjustment, and not sensor replacement. See Calibration.
  1. Remove the filter from the probe by turning it counter-clockwise.
  2. Remove the damaged sensor and insert a new one. Handle the new sensor by the plastic socket. DO NOT TOUCH THE SENSOR PLATE.
  3. Perform a calibration and adjustment using the CRH command as instructed in Humidity Calibration (CRH).
  4. Attach a new filter on the probe. When using the stainless steel filter, take care to tighten the filter properly (recommended force 5 Nm).
    Figure 1. Changing the Sensor
    1
    HUMICAP sensor
    2
    Pt1000 sensor (do not touch)