This unit was designed to control the charging of a secondary (leisure) battery from the primary charging system.
The voltage of the primary battery is monitored.
During charging when its voltage rises above the Switch “On” voltage (26V) then the secondary battery is connected in parallel thus charging both batteries.
After charging when the primary battery voltage drops below the Switch “Off” voltage (25V) and after a short delay then the secondary battery is disconnected, leaving enough charge in the primary battery to start the engine.
The unit switches to low power mode until the primary battery is recharged and the voltage again rises above the Switch “On” voltage then the secondary battery is connected in parallel again charging both batteries.
An override pin allows both batteries to be connected* for emergency use only.
To reduce power consumption to a minimum (10mA “On”, < 1mA “Off”) a latching contactor is used.
When the contactor is “On” the coil is pulsed to ensure it remains on
When the contactor is “Off” the coil is pulsed for approx. 2 minute before the unit goes to low power mode.
The Switch “On” and Switch “Off” voltages are factory set but can be adjusted by the customer.
An internal light emitting diode (led) is used as a multipurpose indicator:
1. led on - the units output is pulsing the contactors coil “On”
2. led off - the unit is in low power mode
3. led flashes each time the contactor coil is pulsed
4. aids setting of the switch “On” and “Off” voltages
*Note:
1. If the override facility is used and the battery voltage drops below 18.0V the Contactor will not disconnect the load. When power is applied to the override pin there may be a delay of up to 30 seconds before the Contactor switches.
2. Before connecting to the power terminals check the Contactor contacts are open. If they are closed apply power to the “Battery –ve” and “Battery +ve” terminals the Contactor contacts should open.