Sterling Relay Ignition Feed 12V 240Amp

Part No: VS-351

Sterling Power affordable low signal activated relay is the simplest in their range, it offers the ability to link together as many battery banks as you need and therefore charge different battery banks on a boat / vehicle when the engine is running.

The relay is ideal for use on boats with outboard motors and simple cabin batteries with no heavy loads on the cabin batteries, small boats/vehicles with auxiliary battery systems with low loads on the auxiliary battery bank which are not in excess of the rating of the relay so as not to overload the relay circuit.

This relay unit features "starter battery interlock", it has the ability to interlock with up to 2 engines starter motors to ensure the relay is inactive when starter motors are engaged, to protect the relay and fuses from blowing. A 30 second start up time delay prevents the relay coming on while the engine is being started, protecting the relay circuit and preventing fuses blowing and damage to the relay.

Benefits over standard relays: A standard relay has an activation feed via a cable. This feed takes about 0.5A to run, which adds the 0.5A to where you are taking the feed from, either the D+ on the alternator or key switch or oil pressure switch. This can place enough extra load on these circuits to cause a problem. There is also the secondary problem of voltage drop in the ignition feed cable affecting the relay. The Sterling IF product overcomes this by only using the ignition feed as a signal and takes no power from the ignition feed wire. The signal then activates an internal control system, which in turn activates the relay from main power circuit internally. This also has the advantage of not suffering from voltage drops in the feed line and allows the relay to run cooler. This unit is also waterproof and in a much safer package form. The package also contains anti-spark protection to help reduce the effect of back EMF from open circuiting the relay under heavy loads, without this relays will weld close if the unit is switched off under high current pass applications. The connection terminals are also high quality brass nuts and bolts gold plated and not poor quality crimp connectors which are not suitable for high sustained current flow.

There is no current limit with this kind of relay, as such, avoid using with systems that have a high secondary battery load, such as a large inverter, anchor winch or bow thruster, as the surge currents associated with this type of equipment can destroy the relay unit (a current limiting relay would be required).