12V 30A SELF SWITCHING SPLIT CHARGE RELAy

[j6393]

I am thinking of fitting a self switching split charge reay to my dual battery system.

Has anyone had experience (good or bad) with the Brocott system currently advertised on eBayhttp://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... 0518349873?

[Eugene Speed]

I have one of those relays on my County, I have two batteries in the engine bay for starting etc, then the relay feeds to a third battery under the crewcab seats to power the worklights over the side and rear doors, the inverter and my power tool chargers. Seems to work fine, not had any problems with it so far. Just make sure you put a fuse at BOTH ends of the wire feeding to the second battery!

Also worth getting a battery monitor panel so you can regularly check the charged state of the second battery, I have a panel with meter, three fused switches and a 12v outlet socket next to mine. Cost about twenty quid on ebay.

[dirtydog]

I have one of those relays on my County, I have two batteries in the engine bay for starting etc, then the relay feeds to a third battery under the crewcab seats to power the worklights over the side and rear doors, the inverter and my power tool chargers. Seems to work fine, not had any problems with it so far. Just make sure you put a fuse at BOTH ends of the wire feeding to the second battery!

Also worth getting a battery monitor panel so you can regularly check the charged state of the second battery, I have a panel with meter, three fused switches and a 12v outlet socket next to mine. Cost about twenty quid on ebay.

Any chance you could do a couple of pics of your set up and if possible a quick wiring diagram?

I've got the 2 batteries under the bonnet but want a third in the back to run my inverter

[Eugene Speed]

To be honest all you need is a positive and negative supply from one of your starter batteries to the relay, and then a single cable from the switched positive output of the relay to the positive terminal of the third battery. I chose to run a seperate negative supply directly back to the third battery for each item that I wanted to connect to it, rather than use the van bodywork as an negative, this keeps all the equipment cannected to the third battery completley electrically isolated from the rest of the van electrics. The relay has an additional couple of output terminals, one is a permanent live and the other is marked for a fridge supply. The permanent live is self-explanatory, and the fridge supply is only live when the ignition is on. The output to the third battery is controlled electronically, only providing charge to the third battery as needed, so as to avoid overcharging. Be sure to fit a 30A fuse between the starter battery and the relay, and then a 30A fuse at each end of the cable between the relay and third battery, use suitable red cable capable of carrying 30A.

I'll try and get a couple of pics sorted. If you order one of the relays you get a wiring diagram and instructions, plus all the terminals on the relay body are very clearly marked! Mine took all of fifteen minutes to fit.

[darkbluevanman]

I am thinking of fitting a self switching split charge reay to my dual battery system.

Has anyone had experience (good or bad) with the Brocott system currently advertised on eBayhttp://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... 0518349873?

I've got one, tried to jump someone off with 2nd batt (engine running) fried the relay on the unit, here's a pick it's in the top right of the pick, like you 2 batt's under bonnet, lesuire to rear... I have a switch to send the split charge to either 2nd batt or lesuire, but not both at the same time

[dirtydog]

To be honest all you need is a positive and negative supply from one of your starter batteries to the relay, and then a single cable from the switched positive output of the relay to the positive terminal of the third battery. I chose to run a seperate negative supply directly back to the third battery for each item that I wanted to connect to it, rather than use the van bodywork as an negative, this keeps all the equipment cannected to the third battery completley electrically isolated from the rest of the van electrics. The relay has an additional couple of output terminals, one is a permanent live and the other is marked for a fridge supply. The permanent live is self-explanatory, and the fridge supply is only live when the ignition is on. The output to the third battery is controlled electronically, only providing charge to the third battery as needed, so as to avoid overcharging. Be sure to fit a 30A fuse between the starter battery and the relay, and then a 30A fuse at each end of the cable between the relay and third battery, use suitable red cable capable of carrying 30A.

I'll try and get a couple of pics sorted. If you order one of the relays you get a wiring diagram and instructions, plus all the terminals on the relay body are very clearly marked! Mine took all of fifteen minutes to fit.

Brilliant thanks for that, will nip off to maplins today and get som decent 30A wire and ge tthe relay ordered from ebay.
Will make it much easier to place the invertor where I want it rather than where the cables reach to from the battery.

oh and I presume a decent car/van battery will do the job as a third battery?

Thanks again

[dirtydog]

I've got one, tried to jump someone off with 2nd batt (engine running) fried the relay on the unit, here's a pick it's in the top right of the pick, like you 2 batt's under bonnet, lesuire to rear... I have a switch to send the split charge to either 2nd batt or lesuire, but not both at the same time

Bloddy hell that's a fair amount of wiring, looks a nice neat job with the fuse holder and relays. What are they all for?

Has got me thinking as I have an extra fuse box next to one of the battery for the beacons etc and it has a couple of spare spaces in it

[johny transit]

oh and I presume a decent car/van battery will do the job as a third battery?

Thanks again

I think that you would want what they call a leisure battery for your extra battery. They are supposedly differnt in that they are better at being drained and recovering than starter batteries, but not suitable for delivering massive crancking amps. I think the plates are thinner internally, although there seems to be a certain amount of sceptisism about them these days (some say they are just re badged starter batteries with a slightly higher price tag). Anyway I will have to buy one soon so let us know what you go for/cost etc!

[darkbluevanman]

''Has got me thinking as I have an extra fuse box next to one of the battery for the beacons etc and it has a couple of spare spaces in it''

Fuse everything as close to the power supply as poss... I have an old Black & Decker 12v drill I converted to run of the fag socket... drill bit jammed and blew the 10amp fuse!... just a lot safer, melted wiring isn't nice!