VOLTAGE SENSITVE RELAY 710-300A

The simplest and most reliable way to run a dual battery system for a 12 or 24 volt supply.

This very high quality Relay is manufactured in New Zealand and allows two or more batteries to be run and charged together. It also allows the isolation of a second battery, and protects the electronics from harmful engine starting spikes.

The relay stays open when the engine is first started and remains open during initial charging until the start battery has reached a preset voltage (13.7V/27.4V). The relay then closes, allowing the two batteries to be charged together. When th engine is stopped, the voltage returns to normal levels, which allows the relay to open again, separating the start battery, eliminating the possibility of charging the wrong battery.

When the voltage drops below12.8/25.6 volts (eg the engine is stopped), the VSR disengages, separating the batteries. This system eliminates the possibility of draining the start battery and protects sensitive electronic equipment powered from the house battery from harmful engine start up spikes.

Advantages of fitting a VSR over conventional charge (diode isolators).

Easy 3 wire connection at the battery. No need to bypass existing alternator wiring. VSRs have no volt drop. Conventional diode isolators incur a minimum of 0.6 volt drop. Compact size - No large heat sink Cost effective solution Dual Sensing:

The 710-300A comes standard with dual sensing. This allows the unit to sense the
start batteries and the house batteries, allowing a single output battery charger to
be used on the house batteries. This parallels the start batteries when house batteries
reach 13.7/27.4 Volts.

Paralleling Function:

The 710-300A can be operated through a momentary button on the dash and will instigate a preset time of 10 minutes. Once this 10 minutes has passed, if the voltage is up high enough for the voltage sensitive relay to operate, it will stay engaged. If not, it will disengage. There is also the ability to have the unit used only as a paralleling solenoid by disengaging the voltage sensitive function.

710-300A Specifications:

• Continuous Rating: 300 Amps DC
• Intermittent Rating: 400 Amps DC
• Parallel Rating: 1250 Amps DC
• Voltage Rating: 12 or 24 Volts DC
• Mounting: Surfaced
• Termination Stud Size: 2 x 10 mm (3/8 “)
• Tin plated copper studs and nuts
• Ignition protected
• Dimensions: 102 x 102 x 107h mm
(4 x 4 x 4.2h inches)

Please click the 'Downlods' tab above for more information.

1. BEP 300A VSR Instructions.pdf

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