Circuit Board Division
800.261.3602
9
Revised 02/21
GSCM-mini-P Automatic Starting for Battery Charging
The GSCM-mini-P can monitor either the generator battery voltage or a battery bank voltage and automatically start/stop the
generator based on battery voltage. This is accomplished by connecting the battery voltage to the battery sense input (terminal
4). The GSCM-mini 60Hz monitors a battery voltage range of 0 to 60VDC and automatically determines the start and stop set
point based on battery voltage (12, 24, or 48VDC). Below 16VDC - uses 12V thresholds, between 16 to 32V -uses 24V thresholds,
above 32V - uses 48V thresholds. This mode is disabled if the voltage on terminal 4 is less than 6V, (no connection).
1.
The GSCM-mini-P monitors the battery sense input and when the battery voltage drops below the start threshold the
Start LED begins blinking every second. When the battery voltage has remained below the start threshold for 5
continuous minutes the auto start sequence begins. If the battery voltage rises above the start threshold during the 5
minute period the 5 minute timing cycle starts over. (Temporary battery voltage fluctuations such as instantaneous
inverter loads will not start the GSCM). The start LED blinks every 3 seconds while the GSCM-mini is running the
generator in auto-start mode.
2.
The GSCM-mini-P starts the generator as described in each of the three generator type sections.
3.
The GSCM-mini-P shuts down the generator (as described in Sections 1, 2, or 3) whenever the battery voltage exceeds
the stop threshold for 10 minutes. The Start LED blinks (every second) during this 10 minute period. The GSCM-mini
will exit the 10 minute period and shutdown the generator if the battery voltage exceeds the stop threshold by +1.0V
for a 12V system, 2V for 24V system and 4V for a 48V system. The generator remains off until the battery voltage drops
below the start threshold voltage.
4.
The GSCM-mini-P will shut down the generator when it has run in auto-start battery charging mode for 6 hours and has
not charge the battery above the shutdown threshold. The GSCM-mini-P then returns to ready mode looking for a start
command. If the battery voltage drops below the Auto start threshold within 30 minutes of a max run time shut down
the GSCM-mini-P will enter a max run time fault condition and lock out the start sequence and requires a power down
reset. The generator Hz LED will blink 3 quick blinks every 5 seconds and the fault LED is on continuously.
5.
If the user wishes to manual-start the generator from a separate pressure switch, level switch, thermostat or inverter
start contact, etc., the battery voltage is fed through the switch (pressure switch etc.) contact to Manual start terminal
5. Closing the contact will cause the GSCM-mini to start the generator. Some inverters provide a switch 12VDC signal
to start the generator. This switched voltage can be connected directly to the manual start terminal 5 and ground
terminal 7.
GSCM-mini-P Generator Emergency Shutdown
The GSCM-mini-P Generator Start Stop module is NOT AN EMERGENCY SHUTDOWN DEVICE! If the manual start signal is
removed the generator will go through a normal shutdown which may take up to 15 seconds to completely shut down the
generator.
A RECOMMENDED EMERGENCY SHUTDOWN SOLUTION is to install a separate “Kill” switch and label it as such. The
recommended wiring is shown on page-2 of these instructions and also in Application 1. Disconnecting the power to the GSCM-
mini module will force the relays to open. This will shut down generators that require a maintained run signal from K1 relay.
However this also prevents the K2 relay from closing to shut down those generators requiring a momentary stop signal. Using
a double pole “Kill” switch and wiring the second pole in parallel with the K2 relay terminals will force the generator to stop in
an emergency situation such as a fuel spill. (See note 1 on wiring diagram, page 2, for Ignition/crank emergency shutdown
option).
