Zamil MAC-240, Installation, Operation & Maintenance Manual

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6. ALARMS AND TROUBLESHOOTING GUIDE
6.1 DESCRIPTION OF ALARMS (FAULT)
This section describes the various alarms that can be shown in the LCD display of the user interface board in the main
control panel. The alarms are handled only if the controller is in “ON” status. Once the alarm condition has been reset the
error message disappears automatically or, in some particular cases, will remain until the ESC button is pressed. Please
refer to the trouble shooting guide for the nature and remedy for each alarm condition.
The description of each alarms are as follows:
a) NO AIR CIRCULATION – This fault is brought about by a “no air flowing” condition sensed by the air flow switch
sensor after a delay timing of 75 seconds, when a signal is already present for the supply fan motor to run. With this
condition, the supply fan motor will be switched “OFF” and LED indicator “NO AIR FLOW” on the panel is lighted. After
the fault condition is corrected, re-set by pressing the re-set button on the panel.
b) LOW AIR FLOW – This alarm serves as a message that the sensed CFM is 10% less than CFM set point. Usually
this may appear during start-up and compressors may not start immediately. Once the CFM has reached the target
set point, the compressors will then start.
c) LAT TR OUT OF RANGE – This fault is caused by an “open” or “shorted” temperature sensor (leaving air temperature
sensor). Compressors are stopped or will not be able to operate. Re-sets automatically after the condition is cor-
rected.
d) TAE TR OUT OF RANGE – This fault is caused by an “open” or “shorted” temperature sensor (ambient air tempera-
ture sensor). Compressors are stopped or will not be able to operate. Re-sets automatically after the condition is
corrected.
e) ADP TR OUT OF RANGE – This fault is caused by an “open” or “shorted” air differential pressure sensor. Supply fan
motor and compressors are switched OFF or will not be able to operate. Re-sets automatically after the condition is
corrected.
f) VFD TR OUT OF RANGE – This fault will appear if the VFD’s feedback signal to ST1 terminal in the microprocessor
board is in “shorted” or “open” condition. This is only a warning and supply fan motor may operate but speed will not
be modulating. Re-sets automatically after the condition is corrected.
g) # SP TR OUT OF RANGE - This fault is caused by an “open” or “shorted” suction pressure transducer. Compressors
are stopped or will not be able to operate. Number shown with the fault corresponds to the particular system where the
fault occurred. Re-sets automatically after the condition is corrected.
h) # DP TR OUT OF RANGE - This fault is caused by an “open” or “shorted” discharge pressure transducer. Compres-
sors are stopped or will not be able to operate. Number shown with the fault corresponds to the particular system
where the fault occurred. Re-sets automatically after the condition is corrected.
i) LOW FUEL – This alarm serves as warning when the fuel level goes down to 30%. The equipment still continues to
operate and the beacon lamp on top of the unit is lighted.
Note:
If this warning is not attended and the fuel level goes further down to 10% level, then the generator engine will shut down.
j) # BREAKER FAULT – This fault appears when the compressor circuit breaker is in switched “OFF” condition or has
tripped. The number mentioned with the displayed fault signifies the compressor number where the fault is. Compres-
sor operation is stopped and the “ESC” button on user interface board is to be pressed to re-set after correction has
been done.
k) # HIGH PRES SWT FAULT – This fault will appear if any of the following safety contacts open:
•
High Pressure Switch
•
External Overload Relay of Compressor
•
Thermal Protection Contact of Condenser Fan
The system (particular to the system number where the fault appeared) is stopped and the “ESC” button on user
interface board is to be pressed to re-set after correction has been done.
l) # SUCTION PRES LOW – If the suction pressure goes down to the pre-set level and timing for low suction pressure
alarm (25 psi for 90sec), then this fault description will appear on the LCD display. The compressor operation of the
system where the fault appeared (described by number with the fault description) will be stopped. Re-setting is
through the “ESC” button after the fault condition is corrected.
m) # DISCHARGE PRES HIGH - If the discharge pressure reaches the pre-set level for high discharge pressure alarm
(400 psi), then this fault description will appear on the LCD display. The compressor operation of the system where
the fault appeared (described by number with the fault description) will be stopped. Re-setting is through the “ESC”
button after the fault condition is corrected.