How To Wire A Tachometer To Alternator

• #1

dgadee

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My engine has had a replacement alternator installed by the previous owner and the tachometer doesn't work at nowadays. This alternator has only three connections - B, L (calorie-free, I think), and R (field, I think). My understanding is that to connect upwards the tachometer from the switch panel information technology needs a quaternary connection (usually w) and this is shown in the engine wiring diagram (below).

Is this true? Or do I just use one connection - R?

I am a chip dislocated because the diagram seems to bear witness the tach connected to both R and W:

http://world wide web.pinksgreen.com/wiring.pdf

Whatsoever advice welcome.

Philip

• #2

Your link doesn't appear to work. I would call up that the "R" terminal is connected to the internal regulator, and extenally to the "ignition switch. (It is for Hitachi alternators anyhow).
IMHO, you lot demand a defended tacho "W" concluding to give the necessary AC output. The other terminals connect to the battery i manner or another and volition non requite the frequency betoken.

• #3

dgadee

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• #4

VicS

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Link seems to be working for me - it is: http://www.pinksgreen.com/wiring.pdf

Alternator is a Mitsibushi 50A 3 wire alternator. Should have said that.

Philip

Thats better, dunno why the starting time link does not work.

The signal to the tacho comes from the W terminal via wire x in the diagram

Information technology is a direct connection to i of the stator coils. Ie it is unrectified Air conditioning.

Sometimes it is a tapping off the coil to deliver only eight volts I beleive.

Other connections to the tacho are the positive and negative power supply and to the illumination bulb.

• #5

For some reason, the 2nd link works for me. Don't sympathise why wires 10,xi and 12 all seem to be joined at the connector, perhaps I'm misinterpreting.
I would expect the tach to have a 12v power connexion, + & -, and a separate point, (W) connection.
Perhaps someone else tin expain.

• #half dozen

dgadee

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I think I get information technology now. Will take it over to my auto electrics man and see whether he volition add a w connection to information technology for me.

Thanks,

Philip

• #vii

VicS

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For some reason, the 2d link works for me. Don't understand why wires x,11 and 12 all seem to exist joined at the connector, perhaps I'm misinterpreting.
I would expect the tach to take a 12v power connection, + & -, and a split up signal, (W) connection.
Mayhap someone else tin expain.

Yeah you are misinterpreting the representation of the 12 way connector

Tach connections explained while you were posting

The one bottom right goes via wire 5 to earth . the one bottom left is the positive ...

Concluding edited: 5 April 2011

• #8

Yes you are misinterpreting the representation of the 12 way connector

Tach connections explained while you were posting

The one lesser right goes via wire 5 to world . the one lesser left is the positive ...

I'll defend myself; that'southward what it should exist in reality, and that's what I said I'd expect, just information technology'due south not what the diagram shows. eg; upper right teminal on "B" appears to indicate wires 10, xi &12 all connected to the same terminal. Lower left on "A" shows 10 & 12 apparently connected. That was part of the OP's trouble I think.
Must accept been drawn by the apprentice draughtsman.

Final edited: 5 Apr 2011

• #9

dgadee

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It is for a vetus m3.10, and then presumably a Dutch amateur.

• #ten

It is for a vetus m3.10, so presumably a Dutch apprentice.

Or mayhap double dutch.

• #11

VicS

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I'll defend myself; that'southward what it should be in reality, and that's what I said I'd wait, simply it'south not what the diagram shows. eg; upper correct teminal on "B" appears to signal wires 10, xi &12 all continued to the same last. Lower left on "A" shows 10 & 12 obviously connected. That was part of the OP's problem I recall.
Must accept been drawn by the apprentice draughtsman.

Ignore the diagram of the connectors. All the wires are numbered. Follow the numbers.

Numbers correspond to colours and presuambly to the way the pins on the connector are numbered. Dont know what color 12 is though!

Last edited: 5 Apr 2011

• #12

david_bagshaw

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It is for a vetus m3.10, and so presumably a Dutch apprentice.

you tin download the owner & installation manuals straight from the vetus web site. in the owners manual are the wiring diags

http://world wide web.vetusweb.com/manuals_63.php

Source: https://forums.ybw.com/index.php?threads/alternator-connection-for-tach.269105/

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