Trying to understand my split charging system

[CovKid]

I'm quite enjoying the flood of chinese PCBs while it lasts. Came home tonight to find another waiting for me. Bizzarely, all their stuff seems to arrive safe and sound unlike items I've bought in the UK that sometimes never arrive or turn out to be faulty - at considerably more cost

Trying to plot the coming year and decide whether to buy a whopping 220ah leisure battery or two 110ah ones....

[Ruralman]

I have 1 x 110 ah leisure battery at present and I intend to add another when funds allow, the latest wiring has leads already laid out ready.
Hopefully this will allow all the 12v devices to be run off grid for 2 or 3 days or so
Regards
Keith

[CovKid]

I'm an off-grid person myself. I find its somewhat a juggling act to have a sufficient power pack and at the same time using efficient low-draw items since you either end up draining the battery or effectively paying a lot for a power pack that is under-utilised. Its hard to get right. For the most part my power pack is for the Propex so something like a 75ah battery is way under what I'd need for a couple of days. I was running with a 110ah but flattened it down to 5v during the Summer (oooer) and in this cold spell its proving to now be gutless so I need to replace it. Not bothered about the size of the battery as mine is now in a cupboard so could be the size of a truck battery really.

However, I'm not convinced this is a leisure: http://www.ebay.co.uk/itm/12V-Ultra-Plu ... SwWnFWAsCH" onclick="window.open(this.href);return false;

[Ruralman]

My leisure battery is also in a cupboard with space allowed for the second battery. I also intend to purchase a folding solar panel kit for additional battery charging
Regards
Keith

[MagicWagon]

Many thanks for the replies.
I looked on the wiki as suggested. From the info on there and by studying and testing my wiring with a meter, I think I'm now happy that it was wired up correctly, apart from the relay trigger coming from the ignition instead of the exciter wire.
I found that the wire was piggybacked onto the ignition wire with a cable lock connector, so I simply disconnected that and connected it to the blue wire leading up behind the dash with a new cable lock connector.
Now everything seems fine. My lights etc now only run off my starter battery if the engine is running, not if the ignition is just turned on. Also, I think now that cranking only uses the starter battery.
The diagram that seemed to make most sense to me in terms of showing what I should be aiming for was this one
http://www.keithandsylvia.co.uk/tech%20 ... usebox.htm" onclick="window.open(this.href);return false; (except I don't have the zig unit supply shown)
The only thing that remains that i'd like to do is to wire my fridge up as per the above diagram so that it only runs when the engine runs (that's assuming the fridge that came with the van works, I haven't tested it yet).
I would also leave the existing manual switch between fuse and fridge so I can stop the fridge completely when not using it.

[California Dreamin]

These have a dedicated 'switched' fridge feed.

http://www.ebay.co.uk/itm/LUCAS-TYPE-SP ... 1849405595" onclick="window.open(this.href);return false;


Martin

[MagicWagon]

Aha. That looks like the relay I already have fitted. I wondered what the extra connector was for (it currently has nothing connected to the 5th terminal).
So I guess I would take a wire from that terminal, via an in-line fuse and the existing manual switch to the fridge ?

[CovKid]

Yes, although as well to check that the terminal is doing what its supposed to do when the engine is running.

[ghost123uk]

Also note that when testing the fridge on 12 Volts, it can take an hour or two before it starts to feel noticeably cold. Obviously it is impractical to drive around for that amount of time just to test the fridge Just so you know, a fridge uses about 7 or 8 Amps, so similar to leaving your headlights on full.

[Mocki]

just a note to add for above, both of the threeway electrolux fridges we have here "draw" almost 11amps in the first 30 mins which reduces as the temp decreases down to about 8amps on test

[Smiffo]

Many thanks for the replies.
I looked on the wiki as suggested. From the info on there and by studying and testing my wiring with a meter, I think I'm now happy that it was wired up correctly, apart from the relay trigger coming from the ignition instead of the exciter wire.
I found that the wire was piggybacked onto the ignition wire with a cable lock connector, so I simply disconnected that and connected it to the blue wire leading up behind the dash with a new cable lock connector.
Now everything seems fine.

Well done MWagon..!!
I'm sure you had a bit of satisfaction solving this one. This was exactly the same symptom I had too, and was also one of the first things I looked at when I bought the van.