A127 Alternator Connections

[iani]

I will be fitting an A127 alternator this week, one question on wiring however. The A127 has a euro connector plug, this gives the warning light and two B+ connections, there is also a B+ post connector. Is there any reason why I cannot route the B+ brown wire to one of the euro plug connectors rather than the post terminal?

Ian

[Hugo]

My (limited) understanding is that modern alternators have an additional sensor wire to detect the battery voltage, rather than rely on the main feed. Apparently this allows better regulation of the charge rate.

[Heuer]

You should have one B+ post which connects to the heavy brown wire to the battery. The other two 'spare terminals are for the alternator coil energiser (12V) and the the remote voltage sensor which is not really necessary in the E-Type as the battery is so close to the alternator. Basically it detects the voltage arriving at the battery and if it is lower than 14.3v caused by resistance in the wiring it signals the alternator to increase the voltage. Would not bother with it personally. The other terminal is for the warning light and it earths when the alternator is not producing juice; it goes high resistance when the voltage rises so dimming the light.

[iani]

Whilst investigating this, I had come across a post that suggested the euro connector was fine for sub 70amp alternators, in any case, I have wired it up with the B+ to the post and only the WL to the euro connector. It's great to see 14.3 volts, even with a slack belt, I'm also seeing my ignition warning light for the first time in over a year

Ian