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Input Wire
The Digital Duo Charge includes a 30-amp, fused 10-gauge cable with two ring terminals. To install the Input Cable:
1. Connect the larger of the two ring terminal connections to the positive post of your house battery. Most marine batteries
will include a secondary stud on the battery lug that will provide a satisfactory connection point.
2. Connect the smaller of the two ring terminal connections to the input terminal of the Digital Duo Charge.
While it may be more convenient to mount the Digital Duo Charge a further distance than is allowed by the length of the Input
Cable, we strongly recommend limiting that distance to the length provided. Again, the shorter length of the input wire allows for
a longer run of the output side of the Digital Duo Charge wiring to add greater ability to address larger loads.
ON/OFF Wire
The fourth and final wire required for basic operation is the ON/OFF wire, which supplies either switched or constant power to the
Digital Duo Charge. If automatic activation of the Digital Duo Charge is desired whenever a source of charging is available at the
house battery bank, the ON/OFF wire can be connected directly to the positive post of the house battery or at the Input terminal
of the Digital Duo Charge (as shown in diagram at right).
When connected directly to house battery voltage, the Digital Duo Charge will remain in a sleep mode whenever input voltage
remains below 13 volts in a 12-volt charging system, or 26 volts in a 24-volt charging system. When voltage at the Input terminal
exceeds that voltage threshold, the Digital Duo Charge will provide charging current to the starting battery. When used in this
mode, the Digital Duo Charge will require a nominal amount of current while asleep (approximately 500mA). If the vessel remains
disconnected from a charge source for an extended period, the Digital Duo Charge can be disabled by disconnecting the ON/OFF
wire from the ON/OFF terminal, or by installing and using an ON/OFF toggle in the ON/OFF wire.
If the Digital Duo Charge is only intended for use when the house battery is being charged by the alternator and regulator, the
ON/OFF wire can be connected to the same switched voltage source that’s used to supply the voltage regulator’s ignition circuit.
To install the ON/OFF wire:
1. Determine the preferred method for Digital Duo Charge activation, and the preferred source for ON/OFF voltage.
2. Provide a length of 14-gauge wire suitable for the intended voltage source and the Duo Charge.
3. Attach one appropriately sized ring terminal or other suitable termination connector, and a 1/4” female spade connector to
the ends of the wire.
4. Plug the 1/4” spade terminal onto the Digital Duo Charge’s ON/OFF connector pin.
5. Connect the other end of the wire, as required, to the desired source of ON/OFF
voltage.
Optional Wiring Connections
While the Digital Duo Charge does provide full functionality with the basic four-wire
connections discussed above, there are a number of optional functions which may provide
additional capacity or intelligence. These include battery temperature sensing and solenoid
control, which enables the manual bypass of the Digital Duo Charge’s internal circuitry and
activation of a solenoid drive circuit that can be used in conjunction with a higher capacity
solenoid relay.
