To calibrate your HMP60 or HMP110 series probe, you need a known stable humidity or temperature reference, and a way to read the output of the probe (Vaisala Insight software, analog output, serial output, the MI70 indicator, or the HM40 meter). As a humidity reference you can use, for example, the Vaisala Humidity Calibrator HMK15.
The probe can be connected to a PC with Vaisala USB cable 219690, and to the MI70 indicator with connection cable 219980. The HM40 meter does not need a specific connection cable.
|The probe cannot be used with the MI70 handheld indicator or the HM40 meter when the probe is in analog mode. To use the probe with MI70 or HM40, enable a serial mode (for example, STOP) in Vaisala Insight software. Use Insight also to return the probe to analog mode.
Connect the MI70 connection cable, the HM40 meter, or the USB cable to the HMP60/HMP110 probe.
- With MI70: Connect the other end of the connection cable to the MI70 indicator.
- With Insight: Leave the other end of the USB cable unconnected at this point. You can connect it to the PC after the stabilization period (4).
- Remove the filter from the probe and place the probe in the reference environment. For example, you can use a NaCl salt chamber (75 %RH) as the humidity reference.
Wait for 20 ... 40 minutes for the reading to stabilize. Do not touch the probe or breathe in its direction during this time.
- If you are using the MI70 indicator or the HM40 meter, you can follow the stabilization using the graph functionality.
- If you are using the USB cable, do not keep the cable connected to the PC during the stabilization period for best calibration accuracy.
After the stabilization period:
- With MI70/HM40: Switch MI70/HM40 off and on to start a blank graph.
- With Insight: Connect the USB cable to the PC and start the Insight application.
- Wait for 1 minute and make sure the graph showing the measurement reading is stable.
- Check the measurement reading, and compare it with the reading shown by the humidity or temperature reference.