Bosch Alternator Regulator LIN

Most alternators will run with a voltage set to around 14.4 if there is no LIN connection. The LIN control allows fine tuning but it's optional.

Peter: This is a carbuild. A Lotus chassie with a Chevy 383 V8.
Im building the electronic system from scratch.

Diver300: That would be the option of running it in failsafe mode without the LIN bus.

Anyone know if the regulator gets its Logic power supplied from the LIN bus wire?

The alternator voltage regulator powers the field winding to adjust the voltage. It needs a couple of amps to do that. The LIN signal itself can't provide that, so the alternator regulator must get power from the B+ terminal.

Ok!

Thanx for the reply! Got what I need to move ahead!
Much appreciated!

Diver300 said:

The alternator voltage regulator powers the field winding to adjust the voltage. It needs a couple of amps to do that. The LIN signal itself can't provide that, so the alternator regulator must get power from the B+ terminal.

Click to expand...

Hi there, I am in a similar situation:

My car originally had a 180A Bosch Alternator but I decided to upgrade to 220A Valeo from a newer car. However the 220A alternator has a regulator with just 1 pin, and ever since the replacement the car would idle at a higher rpm (300rpm more).

I suppose my old alternator was the DFM type and new one has the LIN-BUS type? I saw a post about conversion but the wiring seemed like a pain, would it be okay if I just take out the alternator and change the regulator? Any advantage of LIN-BUS regulator over the DFM ones? Thank you!

Old:


New:

I would not know whether the alternator regulator could be changed. There could be significant differences that would make using one regulator on a different alternator very difficult.

With a different alternator the communication to the car simply won't work. The alternator will most likely have a default behaviour if it can't communicate, and that is probably to run at 14.4 V. The car's default behaviour appears to be to idle at the highest speed that it would if the alternator ever asked for more speed.

Without seeing waveforms etc. it's very difficult to know what the car is expecting.

One possible solution that might work would be to connect the regulator from the old alternator so that it can communicate with the car, so that the idle speed is normal, but leave the new alternator actually generating the electricity.