GE HumiLab, Руководство оператора

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Chapter 5 — Maintenance and Troubleshooting
Reference
measurement
maintenance
The following should be performed as required to maintain the
accuracy needed for your particular application:
• periodic mirror cleaning
• balancing the sensor optics
Details for these procedures are given below.
Problems not resolved by these procedures require the attention of
a person with more in-depth knowledge. The chilled mirror
hygrometer sensor (Model 1111H) generally requires the most
attention because it is the most intricate component of the
Humilab. Information addressing these problems is contained in
Appendix B.
Mirror maintenance
Some Humilab owners routinely perform a mirror cleaning before
each calibration run for best possible system operation. While this
is truly optimum, it is theoretically possible (and generally most
practical) to operate until the system tells you that the mirror needs
cleaning by lighting the letter
“S” (for Service) in the Status
window.
In normal operation, the green “ CONTROL STATUS ” indicator on the
left hand side of the front panel will be lit. The Control Status light
tells you that everything is normal with regard to the control loop
that determines the mirror dew layer.
If the Service indicator adjacent to it does light, momentarily acti-
vate the Pacer® switch. A letter “
P ” will appear in a window on the
front panel. If the Service light goes out after several minutes (at
the end of the Pacer cycle), continue normal operation. If the
Service light remains on after the end of the Pacer cycle, it is an
indication that the sensor mirror requires cleaning. A fine layer of
dust or other contaminant has gradually built up on the surface,
and it must be removed.
Cleaning the
sensor mirror
Periodically inspect and maintain the chilled mirror hygrometer
sensor (1111H) optics as described in the following paragraphs.
These procedures can be done at any time but are only necessary