[stuartb]

Just fitted a Durite  relay.  The red light on the front is always on even when the  ignition and engine are off.  When you start the engine it clicks twice as the red light goes of and comes back on on the second click.  Also.  Battery terminals don't seem to get warm.  Have disconnected it as I think it may flatten my van battery.

Don't suppose anyone can help.  I'm no electrician and am  keen to get it working.

Any help appreciated,
Stu

[RPCCS]

There may be an adjustment screw on it somewhere, and if there is , turn it anti clockwise and see if light goes off. What I did was fit a standard 4 pin relay, that only comes on with the ignition. The relay should cost no more than a fiver and is easy to fit. Plenty of diagrams on google. The relay works by switching between the ignition live, and the auxiliary battery. From pin 86, to ignition live,  85 to body earth,30 to permanant live via 30 amp inline fuse, and 87 to the live of the pump battery. Note that the pump battery needs to connected to a body earth too.

[wayne m]

You should have had instructions with it and that happened to me but if I remember right when I checked it stay on for a bit when ignition off  I think it’s due to it cuts off when the input drops below 12.65 volts  so won’t drain batteries Ive had mine for a couple of years and no problems anI’ll try and find my instructions for you if you’ve lost yours.

[stuartb]

Cheers Wayne,
I've noticed this morning, if when I turn the engine off I turn the lights and radio on and wait ten seconds it turns the relay off.
Do your battery terminals get warm when its charging? Mine don't.  Working today so ill see if it does the job or runs out of juice.

[wayne m]

Not really checked to see if my terminals get warm to be honest. I’ve just been out to the garage and can’t find those instructions anywhere sorry but I think the light staying on is normal as it will go off at some point.

[Spruce]

Just fitted a Durite  relay.  The red light on the front is always on even when the  ignition and engine are off.  When you start the engine it clicks twice as the red light goes of and comes back on on the second click.  Also.  Battery terminals don't seem to get warm.  Have disconnected it as I think it may flatten my van battery.

Don't suppose anyone can help.  I'm no electrician and am  keen to get it working.

Any help appreciated,
Stu

How have you wired the thin black cable? Did you wire it to a good ground? I put a switch in but you don't need to.

What do you mean when you say the light is always on?

When your engine runs the alternator starts charging your starter battery. When the battery voltage at the terminal reads 13.3 volts or something close to that the VSR senses that voltage and switches the unit on. This makes the connection and the leisure battery starts to be charged by the alternator.

Whilst on the move your alternator will be charging both batteries at between 14.2 and 14.6 volts. When you switch your engine off the alternator stops charging. But it takes a while for the voltage on both leisure and starter batteries to stabilise. (A fully charged starter battery will register a voltage of around 12.7v. It takes a while for the voltage to drop to this figure (stabilise.) The voltage sensing relay is designed to break the connection between the batteries when the starter battery drops to around 12.8v. Until the battery drops to that level the batteries will still be linked together.

On my VSR on my old van, these batteries could be linked together for 10 minutes or more after switching the engine off if both batteries were virtually fully charged. Very little power is drawn from the starter battery during this phase.

If the leisure battery had a low charge then it will draw some power from the starter battery which will quickly drop that voltage of the starter battery and cut the connection. It might do that in less than 15 secs.

These units are sealed so there is no adjusting screw. If the unit is faulty it needs to be replaced.

What van are you using this VSR on?

Here's an Ebay link to a similar VSR that has a basic wiring diagram

https://www.ebay.co.uk/itm/12v-Dual-Voltage-Sensing-VSR-relay-eqiv-Durite-0-727-33-12v-140amp-VSR12140HCC/183199158751?hash=item2aa78551df:g:f~wAAOSwNSJa8hHq

[Spruce]

Cheers Wayne,
I've noticed this morning, if when I turn the engine off I turn the lights and radio on and wait ten seconds it turns the relay off.
Do your battery terminals get warm when its charging? Mine don't.  Working today so ill see if it does the job or runs out of juice.

Then the VSR is working correctly. Turning on the lights will draw power from the starter battery and drop the voltage quickly. Hence the reason why the unit cut off.

Sorry, the other posters basically answered the question whilst I was pfaffing on writing a reply.

[Spruce]

The Durite VSR is bi-directional. If you put a battery charger onto the leisure battery whilst connect up in the van, the vans starter battery will also be charged up.

This is why I put a switch on the negative. If I didn't want the unit to work then I just switched off the switch on the black cable to earth. I really used it though.

[RPCCS]

I had one simpler than that. Only 3 wires . live and earth from main battery in one side, live to leisure battery other side, and earth leisure battery to body.
https://www.ebay.co.uk/itm/CAMPER-VAN-VOLTAGE-SENSING-RELAY-SMARTCOM-SPLIT-CHARGE-RELAY-30AMP-MOTORHOME/370837856330?hash=item5657a8a04a:g:J~sAAOSwhspb2enY