Does my Trident have a split charge kit?!

Hi all,

Apologies for the seemingly stupid question, but does anyone know if a) a 1993 Trident with a leisure battery at the back has a split charge relay, and/or b) how to tell if there's one installed?

I'm pretty sure it doesn't have one, but before I fork out to have one fitted I thought I'd ask. Perhaps it's just not working.

The documentation from Autosleeper isn't that clear. It shows that it's possible to have one on the wiring diagram, but doesn't say whether my one has it installed.

Either way, the second battery is kaput. Didn't even hold enough charge to light the fridge gas after a couple of days.


Thanks!

Chris

Is the "after a couple of days" the telling part of this?

The split charge relay charges the leisure battery from the engine alternator when the engine is running. If you've been using the leisure battery without periodically running the engine, the split charge relay can't affect the battery's charge level.

The leisure battery has to be charged from another source when it's being used and the engine isn't running.
This is normally via an on board charger (or PSU/Power Supply Unit), which keeps the battery topped up via an external mains voltage supply (EHU, or just 'hook up').
A second option is charging via a solar panel.

If you've been using the leisure battery without running the engine or connecting to EHU, for more than a couple of days of running lights, TV, water pump, heater fan etc, it will very likely go flat.

Unless I'm missing something, in which case, apologies in advance.

EDIT: An easy way to check the split charge relay would be, if you have a multimeter, check the battery voltage at the terminals with the engine off and with it running. With the engine running you should be getting between 13.x and 14.2 (ish) volts.

If you want to check whether your EHU charger is working, do the same test with EHU plugged in, you should get around 13.8V

With a totally flat battery, both of those readings will drop significantly with either power source switched off.
If your battery has not gone completely flat (less than say, 9-10V) it may well recover as long as you don't leave it flat for too long.
Worth giving it a try at least.

Hi Chris,

Sorry - I should have been clearer. What I meant was that after a couple of days of having been on EHU for hours, with no usage and a 90 minute drive in between, the battery is pretty much flat. The lights come on but very dim, and pump is very half-hearted. We got the fridge lit on the first day of camping, but on day two it didn't have enough charge to even do that.

Many thanks for the advice on the multimeter. I don't have one, but I can get one ordered.

Chris

You'll probably need to state the year of your van to get better specific advice but, is it possible that the EHU charger is switched off, the earlier ones had an ON/OFF switch built into the charger which must be ON for it to work.

Do you know what type of charger you have (is it an older small metal box under a seat or cupboard, or is it a more modern integrated unit in a wardrobe for example), and do you know where it is to check that it's ON when the EHU is plugged in?

(It's Kim by the way, Chris(tine) is the missus.

One thing to be aware of is that when the batteries have a very different state of charge, such as full vehicle battery and tiered LB, when the split charge relay kicks in the batteries are joined and you get a MASSIVE current flow from the strong one to the weak one. This will blow any fuses in the line. Try to find your split charge fuse as well.

meanchris wrote:You'll probably need to state the year of your van to get better specific advice but, is it possible that the EHU charger is switched off, the earlier ones had an ON/OFF switch built into the charger which must be ON for it to work.

Do you know what type of charger you have (is it an older small metal box under a seat or cupboard, or is it a more modern integrated unit in a wardrobe for example), and do you know where it is to check that it's ON when the EHU is plugged in?

(It's Kim by the way, Chris(tine) is the missus.

Sorry, Kim! 

It's 1993. There is indeed a charger switch which is always left on (I'm not sure when there'd ever be call to turn it off, honestly). EHU works fine and everything functions as it should when it's hooked up.

Good point Dave, I hadn't got to that part yet.

meanchris wrote:Good point Dave, I hadn't got to that part yet.

 specialist subject?

meanchris wrote:Good point Dave, I hadn't got to that part yet.

I didn't tell him to do anything with, just find it.

Back to you.

ChrisFilter wrote:

meanchris wrote:You'll probably need to state the year of your van to get better specific advice but, is it possible that the EHU charger is switched off, the earlier ones had an ON/OFF switch built into the charger which must be ON for it to work.

Do you know what type of charger you have (is it an older small metal box under a seat or cupboard, or is it a more modern integrated unit in a wardrobe for example), and do you know where it is to check that it's ON when the EHU is plugged in?

(It's Kim by the way, Chris(tine) is the missus.

Sorry, Kim! 

It's 1993. There is indeed a charger switch which is always left on (I'm not sure when there'd ever be call to turn it off, honestly). EHU works fine and everything functions as it should when it's hooked up.

If the lights, water pump and everything work OK when hooked up, but the battery is flat without hook up, then as Dave suggested, maybe there's either, a loose connection or blown fuse between the charger and battery, or the battery is knackered.
If the lights etc work OK immediately the EHU is disconnected, but then go dim pretty quickly when on battery only, I'd suspect the battery.

dbroada wrote:

meanchris wrote:Good point Dave, I hadn't got to that part yet.

I didn't tell him to do anything with, just find it.

Back to you.

Reminds me of Tony Hancock's "The Radio Ham" - "He's my MAYDAY I got him first"...

meanchris wrote:

ChrisFilter wrote:

meanchris wrote:You'll probably need to state the year of your van to get better specific advice but, is it possible that the EHU charger is switched off, the earlier ones had an ON/OFF switch built into the charger which must be ON for it to work.

Do you know what type of charger you have (is it an older small metal box under a seat or cupboard, or is it a more modern integrated unit in a wardrobe for example), and do you know where it is to check that it's ON when the EHU is plugged in?

(It's Kim by the way, Chris(tine) is the missus.

Sorry, Kim! 

It's 1993. There is indeed a charger switch which is always left on (I'm not sure when there'd ever be call to turn it off, honestly). EHU works fine and everything functions as it should when it's hooked up.

If the lights, water pump and everything work OK when hooked up, but the battery is flat without hook up, then as Dave suggested, maybe there's either, a loose connection or blown fuse between the charger and battery, or the battery is knackered.
If the lights etc work OK immediately the EHU is disconnected, but then go dim pretty quickly when on battery only, I'd suspect the battery.

Thanks again. Battery definitely needs replacing. Then I just need to work out if there's a split charge kit or not. A multimeter should see to that!

I've found lead/acid batteries to be somewhat more resilient than is sometimes suggested.

I've only ever had to throw away two, that I can remember, the first when I was about 22 and the last one, two days ago, which resisted all my loving (and also vicious) efforts to coax it back into life.

Going down the rabbit hole a bit on this one and discovering that I've probably underestimated how quickly it takes to charge leisure batteries. Have invested in a smart 'connect and forget' mains charger and will see if it brings the battery back to life.

I've no idea what to expect in terms of battery life, honestly. It being an old van it has fluorescent lights. We'll use it for those, charging phones/tablets from a 12v USB thing, and the water pump. I wonder if it'll last a week in Cornwall?

ChrisFilter wrote:Then I just need to work out if there's a split charge kit or not. A multimeter should see to that!

Not sure if anyone has said this yet or not, but as far a I'm aware, if the van has a leisure battery, A/S ~always~ fit a split charge relay. On older vans, the mains charger/power supply may have been optional (it was on our 1983 van), but by the mid-90's I would expect both to have been installed from the factory.

As you've probably guessed, the fluorescent lighting is pretty efficient, so that and the water pump won't take massive power. A phone charger should be pretty low on power use as well, though a tablet may be a bit more power hungry.

Oh stop it. The forum software has gone mad.

I didn't know that all vans had split charge mojo, useful to know thanks.

I should have said also that on the 1983 van we did not pay extra for the charger/power supply, and as far as I can recall we never ran the battery flat, but then we only used it for lighting which (with single-tube fluorescents as they were then) is not exactly too demanding on the battery. But we very rarely stayed anywhere for more than a few days, and never as long as a week.

Duplicate post (yes another one).

-mojo- wrote:

ChrisFilter wrote:Then I just need to work out if there's a split charge kit or not. A multimeter should see to that!

Not sure if anyone has said this yet or not, but as far a I'm aware, if the van has a leisure battery, A/S ~always~ fit a split charge relay. On older vans, the mains charger/power supply may have been optional (it was on our 1983 van), but by the mid-90's I would expect both to have been installed from the factory.

As you've probably guessed, the fluorescent lighting is pretty efficient, so that and the water pump won't take massive power. A phone charger should be pretty low on power use as well, though a tablet may be a bit more power hungry.

That's interesting - thank you. On the 1991 Autosleeper material for the Trident (http://www.autosleeper.vwt4camper.info/1991_Volkswagen_T4_Autosleeper_Trident_Owners_ManualWM.pdf) it says the charger is optional if you have a second battery, so both appear to be options (although obviously the charger only becomes an option if you have the second battery).

Fingers crossed we do have one - would save a fair bit of cash in fitting one.

I'm going to swap the fluoro tubes for LEDs also, I think. Should help last a week also.

Do you use the fluoro lights a lot, because the spot/reading lamps are likely G4 halogen bulbs. If you use those a lot then it might be worth exchanging for G4 LEDs.

We've found that we hardly use the fluoro fittings, even though I've converted them all to LED, but we do use the spots all the time in the evening.

meanchris wrote:Do you use the fluoro lights a lot, because the spot/reading lamps are likely G4 halogen bulbs. If you use those a lot then it might be worth exchanging for G4 LEDs.

We've found that we hardly use the fluoro fittings, even though I've converted them all to LED, but we do use the spots all the time in the evening.

Alas we don't have any spot lamps in our Trident. It's only got fluoro tubes. Another thread on the way for that one!

Thanks again for all your replies.

ChrisFilter wrote:it says the charger is optional if you have a second battery, so both appear to be options (although obviously the charger only becomes an option if you have the second battery)

Exactly - as I said, the split charge will always be fitted if you have a second battery, but there is no point in fitting one if you don't! The mains charger/power supply was a separately selectable option when originally bought. The split charge system was not.

-mojo- wrote:

ChrisFilter wrote:it says the charger is optional if you have a second battery, so both appear to be options (although obviously the charger only becomes an option if you have the second battery)

Exactly - as I said, the split charge will always be fitted if you have a second battery, but there is no point in fitting one if you don't! The mains charger/power supply was a separately selectable option when originally bought. The split charge system was not.

Aha. I thought the split charge was an option if the second battery option was taken. Interesting. I wonder why the guy who did our habitation check tried to sell us a split charge kit. Seemed a trustworthy sort!

Thanks - will be interesting to see what the multimeter says. Maybe a fuse has gone. Or maybe the battery was in too poor a condition for the split charge to do much for it.

Please can the forum admin permit us to delete our own (duplicate) posts? The issue with duplicates is a real pain at the moment!