Alternator

[Warren]

Sorry, I know this has been asked before but I didn't understand the answer when I found the thread.

I bought a shiny chrome alternator, Single wire. I cannot see any other connector than a brass/coppery coloured thing on the back. Am I missing something?

If this is it, where does it connect to? Do I need voltage regulator or how do I tell?

Thanks in advance as I have to go away for a few days.

Warren

[craigh]

The alternator would almost certainly have an internal regulator buil in,it can be run up on the vehicle and tested with a suitable multimeter.As for the connections the large main terminal is normally the alternator output,which will find its way to the battery via your cars wiring harness,and there may also be a connection for a charge warning lamp. It all depends on which vehicle your alternator is specified for, connections do differ,some carry a terminal for the excitation circuit also

[SimonP]

Warren,
Is there a hard rubber plug around the rear edge of your alternator?
If there is, you will find the relevant warning lamp and regulator sense terminals hidden under it.

If however it is TRUE single wire, you do not connect the warning lamp. Voltage sensing is done by an internal connection from the main output terminal.
In all cases, the main output terminal connects to battery positive.
Usually it is run to the starter motor main stud terminal because of the very convenient high-current wire direct to battery positive from there.
Wire size should be at least 6mm2, 10mm2 if possible. Because there is no remote voltage sensing in single wire mode, the regulator cannot make up for any volt-drop along the output cable.

As a side effect of having no warning lamp, single wire alternators do not start to charge at idle. You will have to rev the engine briefly, say over 3000rpm for it to "kick in", but from then on, it will continue to charge at idle unless the revs drop too low (or the engine is stopped)

Simon.

[SimonP]

Warren,
Compare this pic of my alternator to your alternator for the location of the terminals.

The GD loom uses 2x4mm2 cables for the output, and an external connection from the main output terminal to the voltage sense terminal (via 5-Amp fuse).
The thin brown/yellow wire that can just-about be seen is the warning lamp connection.
http://www.cobraclub.com/crcforum/user_files/2932.jpg

Hope this helps,

Simon.

[Warren]

Thanks for the info guys. I went routing through the box and there is a small piece of paper that says, "for single wire models" do not use the connections on the outer edge.

I had a closer look at the connection on the back and it seems to have "BAT" stamped at the side of it. Assuming I use the cable 6mm2 as you recommend can I run this straight back to the positive terminal.

The connection is threaded with a nut on it and it appears to be isolated from the alternator body with a red plastic bush.

Cheers
Warren

[Purple AK]

Hi Warren.
Thats the one!
Cheers