How do I connect split charge relay to ignition feed

[greenteaphil]

Hi all,

I'm trying to install a leisure battery system. I've got most things figured out but not sure where to connect the relay. The instructions advise the ignition feed, but where is it and how do I connect to it?

There are a number of fuses behind the battery under the drivers seat. Is it here somewhere?

Thanks
Phil

[wojciech]

Is it Mk7?

[Cider Andy]

On older systems the relay is triggered by the alternator exciter wire: when the ignition light goes out, ie. when the alternator starts to produce current, the relay switches, meaning the two batteries are isolated from each other except whilst charging. But more modern smart charging alternators do not work the same and are not suited to what you are attempting to achieve.

The best thing to use would be a dedicated voltage sensing split charge relay such as the TEC3M, which will cope with most applications and handily includes a switching 12V feed to a fridge, or the heavy duty Durite, which is capable of carrying the entire maximum output current of the alternator.