Author Topic: Alternator wiring  (Read 629 times)

marioxp

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Alternator wiring
« on: March 31 2024, 10:44 »
Please help me with wiring the alternator.  I changed the alternator, until now I had the standard alternator that comes with the VP2030, the new alternator is 100 ah.  I made the mistake of not taking a picture of how the old alternator was connected, I think it was isolated so it needed a minus wire.  As far as I can see, the new alternator minus pole is connected via the housing to the engine. Service technician who installed the motor is not an electrical specialist and obviously connected it incorrectly.  Because the batteries don't charge and the rev counter doesn't work.  I see that the two wires are not connected, but I don't know where to connect them.

tiger79

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Re: Alternator wiring
« Reply #1 on: March 31 2024, 12:01 »
If the original alternator was isolated, that's usually to minimise saildrive corrosion (on later engines the saildrive itself was electrically isolated from the engine).  Fitting an unisolated alternator may give you corrosion issues.

Perhaps ask a marine electrician to take a look and advise you?

marioxp

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Re: Alternator wiring
« Reply #2 on: March 31 2024, 12:16 »
Common minus pole is connected to block of motor. I believe this will not be a problem.  But i will ask. Now I have to solve the wiring first

marioxp

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Re: Alternator wiring
« Reply #3 on: March 31 2024, 12:49 »
I found some more old pictures.

SYJetzt

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Re: Alternator wiring
« Reply #4 on: April 01 2024, 08:43 »
Please provide a photo from the connectors of the new and the old alternator and all cables (colors and thick ess)to be connected.

primozk2a

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Re: Alternator wiring
« Reply #5 on: April 09 2024, 21:20 »
Hi - here's my alternator wiring. Hope it can help. It's a Valeo W7736 - probably not the original VP.

marioxp

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Re: Alternator wiring
« Reply #6 on: April 19 2024, 11:22 »
I'm finally back on board.

These are pictures of the new alternator, unfortunately I don't have any of the old one.

Does anyone have an idea how to connect?


tiger79

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Re: Alternator wiring
« Reply #7 on: April 19 2024, 12:30 »
I think you should get an electrical technician to connect it.

marioxp

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Re: Alternator wiring
« Reply #8 on: April 19 2024, 19:50 »
today I spoke with the man at the company that sold me the alternator.  It says the alternator is isolated.  And that it has the following connectors:
B+ positive pole to the battery
D+ to the indicator light that shows the alternator is charging. 
W to tachometer
B- to negative pole. 
He says there is no sensing wire!  I don't know if I will be able to use this alternator because it doesn't have a sensing wire and I use battery spliter.

tiger79

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Re: Alternator wiring
« Reply #9 on: April 19 2024, 21:07 »
It's possible to add a sensing wire, or you could use a low-loss splitter.  Regardless, I still think you should get an electrical technician to sort out your problem.  With the best will in the world, well-meaning amateurs on here aren't going to solve your wiring issue.  I believe your 2030 engine has an earthing relay, so just connecting B- to the engine block (as you seem to say it was connected) won't work.

marioxp

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Re: Alternator wiring
« Reply #10 on: Yesterday at 22:12 »
I want to announce that the alternator has been redone.  Thank you all for your help and advice.  After many calls, the electrical techician came and solved the problem in 10 minutes.  The only thing is that I didn't connect the sensing wire, he calls it excitation, he disconnected a wire from the alternator and connected the sensing wire to it.  And that was all.