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<< Click to Display Table of Contents >> Navigation: Humidity & Temperature Devices > Transmitter > HF4 > Maintenance > Periodic calibration check |
Both the Pt 100 RTD temperature sensor and associated electronics are very stable and should not require any calibration after the initial factory adjustment.
Long term stability of the ROTRONIC Hygromer IN-1 humidity sensor is typically better than 1 %RH per year. For maximum accuracy, calibration of the HF4 should be verified every 6 to 12 months. Applications where the HF4 is exposed to significant pollution may require more frequent verifications.
The optional keypad of the HF4 allows a 1-point adjustment of temperature or humidity against a reference. A 1-point adjustment has the effect of adding the same offset to all measured values. A multipoint adjustment is not possible from the keypad and requires using either a PC with the HygroSoft software installed or another instrument such as the HP23 hand-held calibrator.
•When the parameter to be adjusted is stable, press the MENU key to show the internal menu on the display
•Use the (-) key to select either H-Adjust or T-Adjust and press the ENTER key
•Make sure that the text line beginning with RefValue is highlighted and press the ENTER key
•Use the (+) or (-) key to change the reference value as desired
•Use the (-) key to highlight the Adjust text line and press the ENTER key
•The HF4 confirms the adjustment with the message “Adjust OK”
•Press the MENU key twice to exit the menu and return the HF4 to normal operation
Notes:
•The calibration point is automatically deleted from the probe memory after an adjustment
•Because the HF4 has no real time clock, the date of the adjustment is not written to the HF4. If retaining the adjustment date is important, use the HW4 software to adjust the HF4.
If so desired, transmission of the HF4 output signals can be validated by using the simulator function. The HygroSoft software is required to enable and configure this function. When this function is enabled the HF4 generates fixed digital and analog signals as specified by the user.