Operating instructions

TM 11574A-OI
2-60
(f) Return -- Yellow LED: Energized when the return air probe is used for control. When this
LED is illuminated, the temperature displayed in the AIRTEMPERATURE display is the
reading at the return air probe.
(g) Alarm -- Red LED: Energized when there is an active or an inactive shutdown alarm in
the alarm queue.
Figure 2-25. Display Module.
LEGEND
KEY FUNCTION
1. Code Select Accesses function codes.
2. Pre-Trip Displays the pre-trip selection menu. Discontinues
pre-trip in progress.
3. Alarm List Displays alarm list and clears the alarm queue.
4. Manual Defrost/Interval Displays selected defrost mode. Depressing and
holding the Defrost interval key for five seconds will
initiate defrost using the same logic as if the
optional manual defrost switch was toggled on.
5. Enter Confirms a selection or saves a selection to the
controller.
6. Arrow Up Change or scroll a selection upward Pre-trip
advance or test interruption.
7. Arrow Down Change or scroll a selection downward. Pre-trip
repeat backward.
8. Return/Supply Displays non-controlling probe temperature
(momentary display).
9. Degrees C/Degrees F Displays alternate English/Metric scale (momentary
display). When set to degrees Fahrenheit,
pressure is displayed in psig and vacuum in “/hg.
“P” appears after the value to indicate psig and “i”
appears for inches of mercury. When set to
degrees Celsius, pressure readings are in bars “b”
appears after the value to indicate bars.
10. Battery Power Initiate battery backup mode to allow set point and
function code selection if AC power is not
connected.
11. ALT. Mode This key is pressed to switch the functions from the
temperature software to the DataCORDER
Software. The remaining keys function the same
as described above except the readings or
changes are made to the DataCORDER
programming.