38 | SAMLEX AMERICA INC.
10. PROTECTIONS
The inverter has been provided with protections detailed below:
10.1 POWER SURGE / OVERLOAD / SHORT CIRCUIT SHUT DOWN
POWER SURGE CONDITION: When the AC output current tries to exceed around 200%
of the rated value, output current limiting is carried out instantly resulting in drop in the
AC output voltage (drop is proportional to the load impedance). Surge Power of around
200% will, thus, be provided for < 8 ms every half cycle. If this situation continues for 2
to 2.5 sec, Overload Condition is activated.
OVERLOAD CONDITION: In case of continuous overload of 110% to 115% for 2 to
2.5 sec, the output voltage will drop. If voltage drops to 80VAC or below, the AC output
will be shut down within 5 sec.
SHORT CIRCUIT CONDITION: The AC output is shut down if the AC output voltage is
80VAC or lower for around 5 sec.
For both conditions of overload and short circuit shut down, the Status LED (2, Fig
6.1) will turn ORANGE and buzzer alarm will sound. The unit will be latched in this
shutdown condition and will require manual reset. To reset, switch OFF the power ON/
OFF switch, wait for 3 minutes and then switch ON again. Before switching ON again,
remove the cause of overload / short circuit.
10.2 WARNING ALARM - LOW DC INPUT VOLTAGE
The voltage at the DC input terminals of the inverter will be lower than the voltage at
the battery terminals due to voltage drop in the battery cables and connectors. The drop
in the voltage at the DC input terminals of the inverter could be due to drop in battery
terminal voltage or due to abnormally high drop in the battery cables if the cables are not
thick enough (Please see details at Section 8.4.3 “Connection From the Batteries To the
DC Input Side of The Unit – Sizing of Cables and External Fuses”). If the voltage at the DC
input terminals drops to 10.5V or lower for PST-150-12 or to 21.0V or lower for PST-150-24,
the buzzer alarm will be sounded. The Status LED (2, Fig 6.1) will continue to be GREEN
and the AC output voltage would continue to be available. This warning buzzer alarm
indicates that the DC input voltage is low and that the inverter will be shut down after
sometime if the voltage at the inverter terminals further drops to 10 V or lower for PST-
150-12 or to 20V or lower for PST-150-24.
10.3 LOW DC INPUT VOLTAGE SHUT DOWN
If the voltage at the DC input terminals drops to 10V or lower for PST-150-12 or to 20V or
lower for PST-150-24, the AC output is shut down. Buzzer alarm is sounded and the Status
LED (2, Fig 6.1) will turn ORANGE.
The unit will reset automatically when the DC input voltage rises to 11.5V or higher for
PST-150-12 or to 23V or higher for PST-150-24.
SECTION 10 |
Protections
