User guide

E-M-HP22-V2_13

Rotronic AG

Bassersdorf, Switzerland

Document code Unit

HygroPalm HP22-A hand-held indicator:

User Guide

Instruction Manual

Document Type

Page

12 of 16

Document title

• As an alternative, cable AC2001 is used to connect the HP22 to a probe input of the HP23 hand-held

calibrator. For service purposes, the HP23 offers essentially the same functionality as the HW4 software.

5.3 Location of the service connector (mini USB type)

WARNING: the service connector is a UART

interface with a mini-USB connector type. Do not

connect the service connector directly to the USB

port of a PC or hub.

The service connector (UART interface) can be

accessed without opening the enclosure after

removing the protective red round cover.

5.4 Periodic calibration check of the probe

Both the Pt 100 RTD temperature sensor used in the probe and associated electronics are very stable

and should not require any calibration after the initial factory adjustment. Long term stability of the

ROTRONIC Hygromer humidity sensor is typically better than 1 %RH per year. For maximum accuracy,

calibration of the probe should be verified every 6 to 12 months. Applications where the probe is

exposed to significant pollution may require more frequent verifications.

a) Procedure for adjusting the probe from the HP22 keypad

Temperature adjustment

The keypad of the HP22 allows only a 1-point adjustment of temperature. The effect of a 1-point

temperature adjustment is to add the same offset to all measured values.

• When temperature is stable, press the MENU key to show the internal menu on the display

• Use the (-) key to select Temperature 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 to match the temperature reference

• Use the (-) key to highlight the Adjust text line and press the ENTER key

• The HP22 confirms the adjustment with the message “Adjust OK”

• Press the MENU key twice to exit the menu and return the HP22 to normal operation

Notes:

o Any temperature adjustment should be done prior to adjusting humidity

o The calibration point is automatically deleted from the probe memory after an adjustment

o Because the HP22 has no real time clock, the date of the adjustment is not written to the probe. If

retaining the adjustment date is important, use the HW4 software to adjust the probe.