Door Open - LabRepCo GM-ULT-1786 Owner's Manual

HIGH AMBIENT TEMP – Activates when the ambient temp probe reading is above 36 C.
LOW BATTERY – Activates when the result of a battery test returns a reading of less than
11.0 VDC.
H S SYSTEM FAILURE – Activates when the high stage heat exchanger probe is unable to
reach at least -33 C after running the high stage compressor for 30 minutes.
L S SYSTEM FAILURE – Activates when the high stage heat exchanger probe reaches a
reading of -55 C or below.
AIR FLOW PROBLEM – Activates when a calculation shows that the difference between
the ambient temperature and the condenser temperature probes is greater than 10 C.
LOW LINE VOLTAGE – Activates when the incoming AC power voltage is below 90 VAC
on a 115 V unit or 180 VAC on a 230 V unit for more than 1 minute.
HIGH LINE VOLTAGE – Activates when the incoming AC power voltage is above 135 VAC
on a 115 V unit or 265 VAC on a 230 V unit for more than 1 minute.
PROBE FAILURE (Control, Heat Exchanger, Condenser, Ambient, Sample) – Activates
when either of the following conditions is detected on this probe: A resistance value over
250 ohms, indicating an open sensor, or a reading below 20 ohms, indicating a shorted
sensor. The same criteria will apply to the remaining probe failure alarms.
PROBE UNPLUGGED (Control, Heat Exchanger, Condenser, Ambient and Sample) –
Each probe has a two-pin logic control as part of its connector, which will be used to detect
that the sensor is properly connected. This alarm shows that the system detected this
probe is not connected. This same description applies to all probes.
FAILED BATTERY TEST – Activates when the result of a battery test returns a reading of
bad battery
.
INITIALIZING
If the display board is unable to initialize properly, the message center will not display any
valid information. This will serve as the indication of a display board initialization
problem. If the main board fails to initialize properly, it will not be able to communicate
with the display board and the display board will report a communication problem, as
described elsewhere.

Door Open

A door open message is displayed in the message center whenever the door is opened. If
the door remains open for more than 1 minute, an audible alarm will sound, subject to
normal silence and ring back functions. If the door remains open continuously for 30
minutes, the remote alarm contacts will activate.
Part number 21729, Rev 4
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