Thread: fitting battery isolator?

Hi all - question about electrics in 94 defender
I am trying to fit a diode isolator that sences the charge that each battery requires inderpendently. Question is it needs a connection from the alternator. Where do I pick this wire up from? There are two brown wires from the alternator one thick and a thin on (I am assuming that the thin wire is for sensing voltage to trip a relay for the starter switch).

Would I be right in assuming that I need to cut the thick brown wire from the alternator connect it to (in) the isolator and then
1/ run a wire from the (A) terminal of the isolator to the second battery pos
2/ connect the other end of the brown wire to the B terminal of the isolator .

Thanks to anyone who replies
paul

Thick brown from Alternator to common (centre) terminal of isolator.
Each of other two isolator terminals go to each battery (original & accessory).
With the diode isolator you will get about a 1 to 1.5 volt drop in voltage at your battery/s compared to alternator output.
Diode isolator won't 'sense' individual battery voltages - it simply isolates one from the other.