SPLIT Charge Stays On ALL TIME

[Johnnny]

Hi my durite split charge relay stays red light on all time even when remove fuse or disconnected from LIESURE battery
Any ideas?
Thanks

 

[Lenny HB]

It's a voltage sensing relay if the voltage on the input side (starter battery) is above the threshold voltage it will turn on.

They are not suitable for use in a Motorhome as they will turn when the starter battery is being charged by mains or solar.

Better to change for a standard split charge relay switched by the D+ from the alternator that will only turn when the engine is running.

 

[Johnnny]

Thanks for reply.it’s just a basic campervan with durite split charge relay.no solar or outside charge.
Was working fine and I realise they stay on a bit after engine turned off.but now mine stays on all time even if take fuse out or remove cable from battery

 

[Johnnny]

ITS as if cable from starter battery is live all the time.even when remove fuse from relay red light stays on

 

[ivorantony]

Very simple to put a relay to the earth return on the Durite so it works the same as a normal split relay but with a higher capacity,
The relay being controlled by the ignition switch,

^{_{Subscribers  do not see these advertisements}}

 

[Johnnny]

I’m sorry I don’t follow.I’m not at all clever with electrics.
Was working fine until yesterday
company fitted diesel night heater and when finished told me my split charger on all time so must be faulty but was fine before.I know they won’t take responsibility but I want to know what they could have done to make this happen.Any help how to fix please?

 

[Lenny HB]

Wondering if they have disconnected it and rewired wrong way round with the input from the leisure battery instead of the starter battery.

 

[Johnnny]

Not sure.they were supposed to be professional company but guy just rude and did shabby job.even wit cups coffee for him.As soon job finished he said heater working fine but my split charge on all time so must be faulty.was fine before though.any ideas how I can work out what to do?as I said I’m no electrician but ok with basics.
also worried in case van won’t start tomorrow because this

 

[Johnnny]

Don’t think he disconnected relay as cables on battery just push on clip type

 

[Johnnny]

I do have a voltmeter but I’m not sure what to test or look for.my set up is cable from starter to leisure battery And earthed.His is from night heater to leisure battery clamped on to same positive clamp on leisure battery

^{_{Subscribers  do not see these advertisements}}

 

[Lenny HB]

Disconnect it for now then check the wiring it's very simple, these images may help.

 

[Johnnny]

Thanks very much I will have a look in morning but definitely something since he wired heater as relay was only fitted last year and been fine up till now

 

[autorouter]

You could do some basic voltage checks.You need to find out if the red light is on because the relay is operating. Alternatively it could be that the relay isn't operating and the red light is on because of an internal fault.

First set the meter to 20V DC range, then measure the leisure battery and starter battery voltages at the battery terminals. The voltages should be very similar, but probably not exactly the same. If they are more than about 0.5V different then the split charge relay is not connecting them.

A relay connecting the two batteries would make them both have the same voltage. It's not a perfect test, because the two batteries could be the same by coincidence, even though the relay is not connected.

To check that possibility, you could switch on a load to the leisure battery. The battery voltage will drop slightly. If the starter battery drops too, then they are connected, and the relay is operating.

 

[Gromett]

Thanks for reply.it’s just a basic campervan with durite split charge relay.no solar or outside charge.
Was working fine and I realise they stay on a bit after engine turned off.but now mine stays on all time even if take fuse out or remove cable from battery

They are crap, but in your use case probably sufficient. Sounds like a faulty one.

 

[Johnnny]

Thanks for replies. What I cannot understand is when I remove the positive feed from starter battery to relay it still lights up.how is this possible without a feed?even when clamps removed from LIESURE battery.
Where is power coming from?

^{_{Subscribers  do not see these advertisements}}

 

[autorouter]

What I cannot understand is when I remove the positive feed from starter battery to relay it still lights up.how is this possible without a feed?even when clamps removed from LIESURE battery.
Where is power coming from?

If the light stays on after you have removed both power feeds, probably there is some energy storage inside the electronics of the unit. Something like a 'capacitor' which acts like a storage tank to smooth out glitches and keep the electronics going during switchover operations. If the only thing draining the capacitor is a single LED, then it can keep going for quite a long time.

 

[GeoffnDee]

Is it possible that the wiring connections at the relay has been used as a power supply for the newly fitted heater ?

 

[Johnnny]

Relay is working as with engine running volts same as starter battery. I'm gonna ignore it few days and hopefully not draining anything. Maybe overthinking things. But definitely from he fitted heater
Thanks

 

[autorouter]

Relay is working as with engine running volts same as starter battery. I'm gonna ignore it few days and hopefully not draining anything. Maybe overthinking things. But definitely from he fitted heater

There's two main problems if the relay is permanently closed. First, when the starter motor is running, it takes a very large current from the starter battery, for a few seconds. If the leisure battery is connected via the permanently closed relay, it will try to contribute to that large current. It may possible damage the battery or blow the main leisure battery fuse.

The other problem is that when using your leisure battery you could accidentally drain all the power, and if the starter battery is permanently connected to it you won't be able to start the engine. If you remove the leisure battery fuse and/or the starter battery fuse, that will prevent both problems.

 

[Johnnny]

Electrics confuse me i seem to have a brain freeze when trying to work it out.what do you suggest to solve?I usually use campsites anyway with ehu if that makes a difference

^{_{Subscribers  do not see these advertisements}}

 

[GeoffnDee]

Are there any fuses that you can remove from the new heater ,to try to eliminate it as to being the possible source of your electrical problem ?

 

[Johnnny]

I have took main feed from heater and still same.what I have noticed is if I check in morning relay light is out so maybe just taking longer to cut off.i give it couple days with everything connected and check voltages on both before and after start engine
Thanks

 

[autorouter]

Electrics confuse me i seem to have a brain freeze when trying to work it out.what do you suggest to solve?I usually use campsites anyway with ehu if that makes a difference

If you remove the fuse at the starter battery end of the feed wire, that will stop any amps flowing along the wire. It will stop the alternator charging the leisure battery while the engine is running, but if you normally use EHU on campsites that won't be a big problem. The habitation electrics will still work OK if you do this.

One possible problem is that the fridge might not run on 12V while the engine is running. Worth checking, it might run through a separate fridge relay so it could be OK.

 

[Johnnny]

Thanks i think I just gonna leave a few days and see what happens. Yes have removed fuse from heater and still same. Might be stressing over nothing and hopefully everything OK.i used to leave lights on when switched engine off to cut out relay and worked fine. Now relay light on alot longer but off when checked next day
I wait and see

 

[Johnnny]

Without starting a new thread is it possible to remove relay and replace with B2B charger using same cable’s.16mmsq.is it as simple just swapping over or more to it?this has probably been mentioned before but just wondering if as easy as straight swapover?

^{_{Subscribers  do not see these advertisements}}

 

[Lenny HB]

Without starting a new thread is it possible to remove relay and replace with B2B charger using same cable’s.16mmsq.is it as simple just swapping over or more to it?this has probably been mentioned before but just wondering if as easy as straight swapover?

Yes you can, depends on cable length and size of the B2B, 16mm sq will be fine with a 30 amp B2B, I wouldn't go any higher unless you know you have an uprated alternator.

 

[Johnnny]

Thanks wouldn't think have uprated alternater as van 2007.about 5 metres cable between batteries. Can you recommend any. Simple to fit lol. Also not got solar but looking at it soon so would need to be compatible. Agm battery at the moment
Thanks

 

[autorouter]

about 5 metres cable between batteries.

It's the length from the B2B to leisure battery that's important. Voltage drop on the starter battery side will be compensated by the B2B. For comparison, 2 x 5 = 10m of 16mm2 wire at 30A will have a voltage drop of 2.7%, which is better than the standard 3% guideline.

 

[Johnnny]

Now I'm confused already. The B2B would be situated right next to leisure battery with 5m cable running to starter battery to supply. My relay is next to leisure battery at back van and hoping just to remove it and replace with B2b using existing cable

 

[Johnnny]

Can the B2b unit be placed next to leisure battery where my current relay is or does it have to be at starter battery which is under cab floor?