ASC+ System Auto Split Charge & Engine Start Protect
User Guide and Installation Instructions
Document No 13362 Issue 04
Page 12 of 21
System operation
The system has two individual functions; ESP (Engine Start Protect) and ASC Auto Split
charge.
ESP (Engine Start Protect) operation
Manual de-isolation (turn system on)
Momentarily press the “Engine Battery On/Off” switch, the primary ESP contactor will close
and the engine loads will now be powered; the switch LED should be on.
Manual isolation (turn system off)
Depressing and holding the “Engine Battery On/Off” switch starts a 3 second timer; at the
end of this time period the primary ESP contactor is pulsed open. During the 3 second
period, the switch LED will flash as stated in the table below.
To prevent inadvertent battery isolation while the vehicle is being driven, the switch is
blocked whilst the vehicle ignition is switched “On”.
Interval
Lamp on time
Lamp off time
0 to 3 seconds
0.2 sec
0.2 sec
Low battery (ESP) protection
When the ignition is “Off” and the battery voltage is below 24.4 volts (12V systems: 12.2
volts), a 3 minute timer starts; at the end of this time period the primary ESP contactor is
pulsed open. During the 3 minute period, the “Engine Battery On/Off” switch LED will flash as
stated in the table below.
The timer will be cancelled if the ignition is turned on or if a charging voltage is detected.
Interval
Lamp on time
Lamp off time
0 - 2 mins
1.5 sec
0.5 sec
2 - 3 mins
0.25 sec
0.15 sec
Battery isolated, and “sleep mode” power consumption
If the battery is isolated, the “Engine Battery On/Off” switch LED flashes as stated in the table
below.
Interval
Lamp on time
Lamp off time
0 - 24 hours
0.02 sec
2 sec
24 + hours
0.02 sec
3 sec
24 hours after battery isolation, the system enters a sleep mode to conserve the remaining
battery charge. Before entering the sleep mode, the system consumes less than 10mA. Once
the system enters the low power sleep condition it consumes less than 1mA.
See Figure 5 on Page17 for a full flow diagram of the “Engine Battery On/Off” switch LED
patterns.
