Which split charge system? Which battery?

Oh well, I was thinking it may just be an input that was split with a schottky in each output, I was thinking schotkky as they (can) have a lower forward voltage drop.

Maybe that's why I don't work in electronics anymore :-)

Not really.The graph of forward voltage drop against current looks like a letter 'J'(its actually exponential) . Until there is a "reasonable" current flowing (relative to the maximum continuous current), the forward voltage could be said to be proportional to current, until the voltage reaches 0.6 volts. Since its proportional to current, even if you share it out, the total dissipation would remain the same or worsen when split over multiple diodes

Steve

"Steve Taylor" wrote

diode test

junction

It depends on the cost of the box. Probably a relay and the volt drop is caused by the thin wires used to connect it.

If expensive then FETs could be used - Field Effect Transistors.

However I have a similar 'black box' (and yes it is black) with one input for the alternator output and three outputs. One for the existing starter battery and two for aux. deep discharge batteries.

But I have a Td5 Defender. From my previous experience of installing split charge devices, the alternator output is a medium thickness brown wire that goes from alternator direct to the battery. This wire is cut and connected to the split charge input and one o/p.

Having received some help here, I've had a quick look under my Defender. The alternator o/p goes direct to the starter. It looks like I'm going to have to remove this wire from the starter and extend it to the split charge box and thence to the battery.

But some have told me there are other problems.

Reg. (electronics eng.)

It's definitely some sort of semiconductor affair.

I've had it rigged up with a battery charger and two sealed lead acid batteries in different states of discharge and it seems to work fine. You can only use it to charge batteries with though, you won't be able to pull any power from the alternator through the unit as its only rated upto 8A.