Page
46
Appendix B — Humilab chilled mirror hygrometer
• A dew point sensor (GE General Eastern Model 1111H)
• A Temperature Sensor (GE General Eastern Model T-100E)
• Interconnecting cables (part of the Humilab)
Front panel operation and displays
The front panel was discussed in Chapter 2 from a daily operations
standpoint. This section repeats some of this information (for quick
reference), but also supplies additional information.
Figure 7 on page 17 shows the front panel layout. The panel
contains digital dew point and control status displays and three
operating switches:
SENSOR
,
BALANCE
and
DISPLAY
. The lettered
sections below correspond to the labels in page 17.
A
DEW POINT
display — The
DEW POINT
display shows the dew or frost point in
Celsius or Fahrenheit units.
B,C
CONTROL/STATUS
display — The
CONTROL/STATUS
display includes a green
control light and a seven-segment display. The control lights comes on when
the system detects both a stable dew or frost layer and a stable dew point
temperature. The seven-segment display indicates as follows:
P
Programmable Automatic Contaminant Error Reduction
(PACER®) mode or Automatic Balance (
AUTO
) mode is in
operation.
S
Service — The system optics require service, cleaning, or
adjustment.
(bars)
Indicates the approximate amount of condensation on the
sensor mirror. (Only seen in
HEAT
or
COOL
mode.)
D
DISPLAY
Switch — This is a three-way switch that selects:
NEXT
A momentary position used when viewing or changing
OPERATION
Normal operation.
SELECT
A momentary position used when viewing or changing dis-
played unit, output unit and scaling or alarm units and limits.
E
BALANCE
switch — This is a three-way switch that selects:
AUTO
The Pacer/Auto cycle occurs at a pre-selected interval.
