Blue Sea ACR Wiring Question

[luthj]

Generally speaking B+ is attached to the battery positive terminal, so there is no difference between the battery and the B+ terminal. Obviously you should never attempt to run the alternator with the B+ not connected to the battery.

With your meter set to ohms, and the D+ disconnected, what is the resistance between the D+ and the alternator case? Just curious.

 

[DaveInDenver]

Oh! I didn’t connect D+ to B+. I just connected D+ straight to the battery via the distribution block. I can try jumping D+ to B+ when I get home from work this afternoon.

That doesn't matter, connecting them together on the back of the case or running a wire from the battery would achieve the same thing.

The problem is, even with a direct supply of 12v from the battery the D+ terminal is only getting 0.1-0.2v.

That is with any of the voltage regulators mounted?

 

[luthj]

That 0.1-0.2V, is that between D+ and the alternator case, or?

 

[DaveInDenver]

That 0.1-0.2V, is that between D+ and the alternator case, or?

That line of reasoning is a good possibility.

With your meter set to ohms, and the D+ disconnected, what is the resistance between the D+ and the alternator case? Just curious.

Also @Tiktaalik please make this measurement with both polarities on the leads. First with red on D+ and black on alternator case. Then reverse them, black on D+ and red on alternator case.

It would be ideal if you could measure between case, DF and D+ in the same way with the regulator removed on both the regulator and the alternator but that is probably getting too off in the weeds. My suspicion is the problem isn't the alternator.

 

[Tiktaalik]

Thank you for all our patience and knowledge! I will follow your recent suggestions when I get home from work.

Meanwhile I have another question. Currently the two B+ wires are combined into one and they go from the alternator to one post in the distribution box. The stock wiring diagram however shows the following (see attached image). Can you tell me what the symbols marked in red means?

 

[luthj]

The one symbol is a connector symbol (there are others on the diagram). The two parallel lines symbol represents a capacitor. Probably to filter ripple current or maybe electrical noise? One side is connected to the B+ the other to ground. Its possible the new alternator doesn't need a capacitor, as better quality regulators have internal filtering to prevent generating noise/spikes. I would consult the builder of the alternator.

 

[DaveInDenver]

Parallel lines can also mean the contacts of a relay in some contexts but when it does it'll usually have some indication of their association with a coil somewhere. Hard to say 100% but in the screen shot you give I'd assume capacitor from B+ to ground too. The alternator you showed has a capacitor mounted on the back so it could be something Bosch or the manufacturer (Mercedes, VW, etc.) considers optional or may install in different places in harnesses of difference vehicles.