Alternator exciter

[Ed]

GUys,

ive recently installed an alternator off a JE camria.

it requires an exciter voltage.

Normally these are run with a 1-2W bulb, however I decided not to use the bulb and used a 0.5W 300 Ohm resistor.

The problem is now I've blown 2 regulators, is the resistor ive used too small?

the alternator works and charges to 14.0 Volts for a while then it just dies..

any ideas?

Cheers

Ed

 

[Ed]

After some phone and internet research in brief moments between work I have managed to get a replacement regulator.

The auto electrical industry appears reluctant to  let go of any information related to the mysterious "exciter circuit" and ways to circumvent the use of an "idiot light" to apply the required 2W loading on this circuit.

anyway.. i have found a resistor from www.electricboatparts.com.au  P/N 101030 which has been selected specifically for Bosch alternators and for use without the warning lamp. it also has a nice large cermaic heat sink.

You could also use a resistor from jaycar for probably 25cents but the risk is getting it wrong and frying your reg.  At $40/ regulator mistakes end up being costly.... ask me how i know.

you could also simply run a 2W globe in series on the "L" circuit if you want a warning light.

Hope this is of some help to anbody contemplating using a Bosch alternator.

Cheers

Ed

[fctoy]

hi ed you can run ignition supply to the warning light terminal & put a 3 amp diode in the circuit so there is no feedback. As far as the regs blowing up using a resister as you have wont cause this to happen sounds like you have been unlucky with  2 regs or you have got a faulty rotor with to high field circuit which will fry regs.

[Ed]

hey fctoy,

thanks for the advice,

Ends up the regs were fine, my "new" wiring was fine.
it was the pulleys on the idler and alternator having the incorrect V size.  it caused the belt to slip and no charge.

sometimes it's the easy stuff!  I now have some spare regs to pack in the tool box.

Cheers

Ed