1-point adjustment of HMT330/PTU300 using a calibrator - HM70 - HMT330 - PTU300

HM70 User Guide

Document code
Document type
User guide
This procedure is 1 of the alternative methods for completing the adjustment described in Calibrating and adjusting HMT330 series and PTU300 series transmitters.

When adjusting a transmitter in only 1 reference condition, make sure that the reference condition represents the measurement environment well.

If you use Vaisala Humidity Calibrator HMK15, use the adapter fitting (13.5 mm) on the measurement hole if you calibrate probes of HMT334, HMT335, HMT337, or HMT338 transmitter models.

To complete the adjustment:
  1. Remove the filter from the transmitter's probe and insert the probe into the reference condition.
  2. Press Adjust to continue adjusting.
  3. Select 1-point adjustment from the MI70 adjustment menu and press Select.
  4. Press Ready when the reading has stabilized in the reference condition (note that the stabilization may take 30 minutes or longer). You can follow the stabilization from the graphical display by pressing Graph.
  5. Enter the correct reference value with the arrow buttons and press OK.
  6. Confirm the adjustment by pressing Yes.
  7. The adjustment is done. Press Back and Exit to return to the basic display.
  8. Switch off MI70 and detach the calibration cable.