Quantech QWC3050T-200T, Installation Operation & Maintenance

Page: 119 / 186

SECTION 7 – UNIT CONTROLS
FORM QWC3-NM1
ISSUE DATE:11/20/2020
QUANTECH
119
7
U N I T F A U L T :
1 1 5 V A C U N D E R V O L T A G E
The Under Voltage Safety assures that the system is
not operated at voltages where malfunction of the mi-
croprocessor could result in system damage. When the
115VAC to the micro panel drops below a certain level,
a unit fault is initiated to safely shut down the unit. Re-
start is allowed after the unit is fully powered again and
the anti-recycle timers have finished counting down.
U N I T F A U L T :
H I G H M T R C U R R
When the CURRENT FEEDBACK ONE PER UNIT
option is selected under the OPTIONS key, the unit will
shut down when the voltage exceeds the programmed
trip voltage for 5 seconds.
The trip voltage is programmed at the factory accord-
ing to compressor or unit RLA.
Restart will occur after the anti-recycle timer times out.
Unit Warning
The following messages are not unit safeties and will
not be logged to the history buffer. They are
unit warn-
ings
and will not auto-restart. Operator intervention is
required to allow a restart of the chiller.
! ! L O W B A T T E R Y ! !
C H E C K P R O G / S E T P / O P T N
The Low Battery Warning can only occur at unit pow-
er-up. On micro panel power-up, the RTC battery is
checked. If a low battery is found, all programmed
setpoints, program values, options, time, schedule, and
history buffers will be lost. These values will all be re-
set to their default values which may not be the desired
operating values. Once a faulty battery is detected, the
unit will be prevented from running until the PRO-
GRAM key is pressed. Once PROGRAM is pressed
the anti-recycle timers will be set to the programmed
anti-recycle time to allow the operator time to check
setpoints, and if necessary, reprogram programmable
values and options.
If a low battery is detected, it should be replaced as
soon as possible. The programmed values will all be
lost and the unit will be prevented from running on the
next power interruption. The RTC/battery (031-00955-
000) is located at U17 on the microboard.
I N C O R R E C T
U N I T T Y P E
This indicates the condensing unit jumper is installed
on J11-12. This jumper must be removed to operate the
chiller.