Bosch Style Alternators

[101RRS]

I have put in a Bosch style alternator into my vehicle. It has B+, D+ and W connector spots on the back. I believe B+ is the main large cable to the battery, D+ is the field ignitor/ignition light connector but I am not sure what the W connector is?

I have to wire this into the old army wiring and components and I need to be sure I have everything covered. I have taken out the alternator control box behind the front wheel arch as I believe this essentially works as a regulator and the new alternator has this inbuilt. I have left the amp meter shunt box on the outside of the battery box (the amp meter has never worked) as it has a number of wires that go forward to the dash area and even with the wiring diagram I cannot work out what is going on there. In the shunt box I have worked out where power from the alternator comes in and the connectors for the ignition light to the alternator so I will leave all this in place.

The main issue I have is working out whether I need this W connector of the alternator connected or not.

Thanks

Garry

[PhilipA]

Tacho so no.
Google (https://www.google.com.au/?gws_rd=ssl#q=bosch+alternator+w+terminal&*&spf=109)
Regards Philip A

[rangieman]

Google says[bigwhistle]
https://lh3.googleusercontent.com/proxy/wox7LgubAavKfnnD4SDXEDi6MaYfT9PAUI2DkZT6TuXoFPr3A8 zV5U_rFJXNl1mLYJNQSbvD7PWyCB5HlppjlV3Dv9yEASRCTooD N1Cn9FeU9JMRyh6JYjznpSa30TVh2XtkXtGrkbp-ZLdPjS8Azvgh0iyOAHaMA73j3M6jq0nZW1uPviCYiN5fAf5jHq KZs_w7PswGaSGPgkmqTlJQlBkAaTvVzA2DO7YXNuDyy1ZJJZ4U kvoLjnPGpG7DxwKfpVhhFSj-kA=s600-p-k-rw

[101 Ron]

To the best of my memory,......B heavy wire battery positive
D + is supply from ignition circuit for voltage sensing (D stands for the old term dynamo )
W is for warning light........Connect to warning light with the other terminal on the warning light to ignition supply.

[101RRS]

Thanks for the responses - well yes I had googled and got a who lot of mixed messages - some said tach (then why not a T) and others said as Ron mentioned W for warning.

So hence the question to the brains trust.

Thanks

Garry

[bee utey]

W connects directly to the field windings and therefore puts out an AC signal related to the rpm. Some carby Falcons in the 80's used this terminal to drive a heating element for the automatic choke. This stopped the choke from opening prematurely if you switched on the ignition and waited before starting the engine. It does not need to be connected to anything. B+ (battery) and D+ (warning lamp) are the only connections you need to run an internally regulated Bosch alternator of the traditional kind. Voltage sensing is internal and requires only a good battery connection at B+. The thicker the battery cable is the more closely alternator voltage matches the battery voltage.

This article (http://www.buchanan1.net/charge.html), although about BMW bikes, is quite adequate in explaining how a standard Bosch alternator works.

[Homestar]

As mentioned by others, definately tacho, so just leave it alone. I've fitted a couple of alternators with this terminal that haven't had them so they can be used in RRC's. A simple tapping into the field windings.