TROUBLESHOOTING GUIDE
SYMPTOM
On switching on, LED (2) does
not light. Buzzer is off. There
is no AC voltage.
Buzzer alarm is sounded
when load is switched on.
Voltage at DC input terminals
reads between 10 and 10.5 V
for PST-30S-12A or between
20 & 21 V for PST-30S-24A.
LED (2) is green.
AC output voltage is
available.
Buzzer alarm is sounded when
load is switched on. Voltage
at the DC input terminals
reads below 10 V for PST-30S-
12A or 20 V for PST-30S-24A.
LED (2) turns orange.
There is no AC output.
There is no AC output.
LED (2) turns orange.
Buzzer is on.
POSSIBLE CAUSE
There is no voltage at the DC
input terminals.
Polarity of the input voltage
has been reversed that has
blown the internal DC side fuse.
DC input voltage is less than
10.5 V for PST-30S-12A or less
than 21 V for PST-30S-24A.
Shut-down due to low input
DC voltage (Less than 10 V for
PST-30S-12A or 20 V for PST-
30S-24A).
Shut-down due to high input
DC voltage
(> 16.5 V for PST-30S-12A or 33
V for PST-30S-24A. ).
REMEDY
1. Check the continuity of the
battery input circuit.
2. Check that the battery fuse
is intact. Replace if blown.
3. Check that all connections
in the battery input circuit are
tight.
Correct the polarity of the
input connections and replace
the internal fuse (
Note:
Reverse polarity may cause
permanent damage).
If the unit does not work after
replacing the fuse, the unit has
been permanently damaged.
Call Technical Support.
1. Check that the battery is
fully charged. Recharge, if low.
2. Check that the battery
cables are thick enough to
carry the required current
over the required length. Use
thicker cables, if required.
3. Tighten connections of the
battery input circuit.
1. Check that the battery is
fully charged. Recharge, if low.
2. Check that the battery
cables are thick enough to
carry the required current
over the required length. Use
thicker cables, if required.
3. Tighten connections of the
battery input circuit
1. Check that the voltage at
the DC input terminals is less
than 16.5 V for PST-30S-12A or
33 V for PST-30S-24A.
2. Ensure that the maximum
charging voltage of the
battery charger / alternator
/ solar charge controller is
below 16.5 V for PST-30S-12A
or 33 V for PST-30S-24A.
3. Ensure that an un-regulated
solar panel is not used to
charge a battery. Under cold
ambient temperatures, the
output of the solar panel
may exceed 18 V for a 12 V
battery system or 36V for a
24V battery system. Ensure
that a charge controller is used
between the solar panel and
the battery
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