Isolator switch

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Posts: 77
Joined: Sun Oct 14, 2007 12:51 pm
Location: Ireland

Isolator switch

Post by eddiem » Wed Jan 23, 2013 5:19 pm

Hi should a isolator switch be wired to the negative or positive lead on a tractor which has negative earth or does it matter which lead you use ?


RE: Isolator switch

Post by Guest » Wed Jan 23, 2013 6:27 pm

Assuming that you wish to fit an isolating switch as a theft precaution you could do one of two things or devise your own method. There are isolators that you can fit by breaking the POSITIVE cable from the battery to starter motor but it needs to be fitted in a way that it can keep out any water, dirt and corrosion and the only place you'll be able to site it without lengthening the existing cable to somewhere no-one can find the switch is in the front of the bonnet but in putting one of these in the cable a theif only needs to follow the cable to find it but in doing that you greatly reduce the power from the battery. Strictly speaking, the ignition key switch is the isolating switch and fitting another 2-pole key switch between the feed wire from the ignition switch to the other key switch and then back to the other spade on the ignition switch would serve the purpose much better. You can still get these old type key switches, they are the type that were fitted on old cars where you first turned the key and then started the engine by pressing a button. One thing for sure is that a would be theif would not have a duplicate key and would probably not be able to get their hand up under the dash to 'hot-wire' it. If your tractor is a Q cabbed model or later then this method would be even better as you can't get at the wiring without going behind the dash without the right tools.

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