DMCH alternator

[Ron]

$.02:

Don't hold me to it, but without looking at that type before, I'd bet it's odd behavior(s) is due to not utilizing a battery sensing circuit, as expected?? :

[Bitsyncmaster]

$.02:

Don't hold me to it, but without looking at that type before, I'd bet it's odd behavior(s) is due to not utilizing a battery sensing circuit, as expected?? :

Good idea Ron. I was looking at patents today to see if anything new was showing on Automotive regulators. Looks like some new ones are using a microprocessor which would explain the flashing self test.

[Bitsyncmaster]

So it looks like I should try connecting the "S" pin to the battery (always 12 volts).

Why would the "S" pin need a heavy wire if all it does is remote sense the voltage?

Connector is labeled S F L P.

We use the "L" for the light. Some use the "F" with a switched 12 volt feed. So what is the "P" for?

[Bitsyncmaster]

Found the definitions.

[Ron]

So what is the "P" for?

(P)ulse.
For diesel engines...no ignition/tach signal!

NOTE: Your pic says, "battery positive", but normally it should be fused and switched B+.
You could simply strap it to the alternator's battery terminal, but they want it wired to ignition due to ~1V drop across the wiring....
[Assuming standard setup here]

[DMCMW Dave]

NOTE: Your pic says, "battery positive", but normally it should be fused and switched B+.
You could simply strap it to the alternator's battery terminal, but they want it wired to ignition due to ~1V drop across the wiring....
[Assuming standard setup here]

Actually if you just leave it disconnected it will internally regulate. Which is the "normal" installation. Just the output wiring bundle, and the one wire to the idiot light.

[refugeefromcalif]

Did DMCH stop selling the Motorola 140 A alternator? The part # that was posted specifies a 120 A alternator.

George

Anybody know? I've searched the DMC website and only find the 120A.
I've had the the Motorola 140 installed for about 2 years and yesterday had an issue with it, (Or the charging system in general). Thunderstorms halted my diagnostics.

George

[Ron]

Actually if you just leave it disconnected it will internally regulate. Which is the "normal" installation. Just the output wiring bundle, and the one wire to the idiot light.

Thanks!
For future reference, do ya know if it is a SFLP or SILP??

[DMCMW Dave]

Thanks!
For future reference, do ya know if it is a SFLP or SILP??

No, I don't.

[Bitsyncmaster]

Thanks!
For future reference, do ya know if it is a SFLP or SILP??

Both connectors (Johns and DMCH) are exactly like the picture I posted. SFLP

I don't think the remote sense will fix the "dip" problem but I'm going to test it anyway. I would assume if the sense line has a lower voltage than the output terminal on the alternator it will boost the voltage. I'm not worried about voltage drop over the wires since I have a 4 AWG wire about 2 foot long going to my buss bar. I'm seeing 14.6 volts on the buss bar to engine ground.

I will also try powering the "F" terminal to see if that corrects the "dip".

Since I saw the dip go to 48 amps, maybe other cars that only run the stock idle ECU (775 RPM) can only provide 48 amps and they would not see the dip.

Does anybody know what the flashing would be for normal self test and what it would be if it found something wrong?