Zamil MAC-240, Installation, Operation & Maintenance Manual

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6.2 TROUBLE SHOOTING GUIDE
FAULT DESCRIPTION PROBABLE CAUSE
a) Loosed wiring connections on relay
AR4-3B (NC) terminal to terminal A11
of MB board.
b) Clogged or crimped hose fixed at high/
low pressure outlet of air flow switch.
c) Defective AR4 relay.
d) Defective time delay switch (TDS)
VFD Fault
a) Open or loosed wiring connection of air
pressure sensor to terminal RH of MB
board.
b) Shorted or defective sensor
Open or loosed wiring connection of VFD’s
feed back signal to terminal ST1 of MB
board.
a) Open or loosed wiring connection of
supply air temperature sensor to ter-
minal Tout of MB board.
b) Shorted or defective sensor
a) Open or loosed wiring connection of
ambient air temperature sensor to
terminal TAE of MB board.
b) Shorted or defective sensor
a) Open or loosed wiring connection of
suction pressure transducer to termi-
nal S1 or S2 of MB board.
b) Shorted or defective sensor
a) Open or loosed wiring connection of
discharge pressure transducer to ter-
minal D1 or D2 of MB board.
b) Shorted or defective sensor.
a) Compressor circuit breaker is “OFF”
b) Breaker auxiliary contact wiring to A2
or A7 terminal of MB board is loose.
c) Compressor circuit breaker has
tripped.
a) High pressure switch opened
b) External Overload Relay Contact of
compressor opened
c) Cond. Fan motor thermal contact is
open.
CORRECTIVE MEASURE
- Check and Re-tighten wiring connec-
tion.
- Remove the clog or straighten the
hose.
- Replace Relay.
- Replace time delay switch.
Check VFD LCD display for error code
and refer VFD manual for possible cause
and corrective measure.
- Check and re-tighten connection.
- Replace sensor
Check and re-tighten connection.
- Check and re-tighten connection.
- Replace sensor
- Check and re-tighten connection.
- Replace sensor
- Check and re-tighten connection.
- Replace sensor
- Check and re-tighten connection.
- Replace sensor
- Switch breaker to “ON”
- Check and re-tighten connection.
- Check ampere setting of breaker and
adjust to proper setting.
- Compressor winding could be shorted
or grounded. Replace compressor.
- Check pressure switch setting and
adjust. Replace if defective.
- Check overload setting and adjust correctly.
- Check compressor contactor contact points for
carbon deposits. Clean or replace contactor.
- Thermal contact may close automatically when
cooled. Check condition of motor winding. Re-
place fan if winding is damaged.
SYMPTOM
Supply Fan
Motor Stopped
or Not Starting
Supply Fan
Motor Speed
not Modulating
Compressor
Stopped or
Not Starting
LCD DISPLAY
No Air Circulation
VFD Fault
ADP Tr Out of
Range
VFD Tr Out of
Range
LAT Tr Out of
Range
TAE Tr Out of
Range
SP Tr Out of
Range
DP Tr Out of
Range
# Breaker Fault
# High Pressure
Switch Fault