GE HumiLab, Руководство оператора

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Appendix B — Humilab chilled mirror hygrometer
equilibration time. On the Humilab simply compare the upper
reading (if set to dew point) with the lower reading (tempera-
ture). They should agree.
3. If the platinum resistance thermometer in the dew point sen-
sor is faulty, return the sensor to GE General Eastern for fac-
tory servicing. (See Appendix E for return procedures.)
“P” remains lit on the front panel.
When “ P ” remains lit on the front panel, the instrument has not
recovered from a Pacer cycle.
• Check that the sensor and sensor cable are connected. If they
are not connected, connect them now. The instrument will
come out of Pacer mode after a short time.
• The sensor optical bridge may be out of balance. Perform the
optical balance procedure as described in Chapter 5.
No analog output, but the digital display operates.
Check the analog output scaling. See the scaling procedure in
“Scale outputs” on page 53.
No digital output from the RS-232C port.
The instrument may not have been scaled properly via the
RS-232C port. Repeat the procedure in the Scale Outputs section in
“Scale outputs” on page 53.
Have you established proper communications, correct COM port?
See Appendix C for information.
No cooling and/or heating.
The front panel dew point display should indicate if you are not
getting heating or cooling. When you turn on the sensor
HEAT
switch, the digital display should show an increase in temperature.
When you turn on the
COOL switch, it should show a decrease in
temperature.