Split Charge

[enak]

After installing a second battery and a split charge relay, I had a problem.

I connected the relay to the battery light wire (brown/ yellow) from the alternator down near the multiconnector (on the right hand side).  It worked ok for a few minutes and while driving my instrument lights went bright!  I checked the alternator voltage and it was outputting 15-17 volts (depending on revs).

After disconnecting the relay, the alternator output is fine (14v - 14.2v).

Is something wrong with my alternator?  Or is this relay unsuitable for connection to this wire?

Where can I buy a voltage sensitive relay from?

[Range Rover Blues]

Voltage sensitive relay for the purpose of charging a caravan battery is available from Towsure and all good caravan accessory dealers.

[enak]

Thank you!

this is exactly what I am looking for.

[enak]

Finally got the spilt charge sorted at the weekend... While browsing my work shop manual I noticed the option for split charge in the wiring diagram... it works off the voltage sensitive relay and ignition to provide the same function as the circuit I got from tow sure.

So now everything is wired in and working!

[enak]

Here's a picture of the installation for reference if anyone else tries this



My relay is a 500amp which should be enough for the range rover :D
There is a module on it to prevent back EMF and reduce power usage to it matters which way round it is connected.

The red wire from my relay connects to the white wire (Ignition feed).
The black wire from my relay connects to the brown/black wire in the loom (voltage sensitive relay).
The yellow cables on top are heatshrinked 4 gauge cable.
Left one is a feed from the alternator (which in turn connects to the other battery).
Right one is the positive on the auxilary battery.

[Range Rover Blues]

Cool.  I'm looking for a very small 12V battery as there isn't room for a full-sized one on some cars.

[enak]

Something like this could work for you.

But with smaller cars, sometimes it is best to just uprate the main battery.

[Range Rover Blues]

Not a bad idea actually, given that is what is fitted inside those portable booster packs anyway.