Regulator rectifier wires are getting very hot

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Robotnik
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Regulator rectifier wires are getting very hot

Post by Robotnik » Sun May 21, 2017 7:11 pm

I noticed today that the 3 white regulator rectifier wires are getting very hot.
I'm busy cleaning up all the connectors and the v-reg mountings at the moment, is it usual for them to get so hot or have I got another problem?
Neil

Evilchicken0
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Re: Regulator rectifier wires are getting very hot

Post by Evilchicken0 » Mon May 22, 2017 9:19 pm

Things can get warm down there the reg part heats up. You can test them but I'm not sure the procedure. I have a tester for the whole charging circuit, it's a Blue Point MT130 easy to use too, they stopped making them but they come up on ebay (usually in the usa)

Robotnik
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Re: Regulator rectifier wires are getting very hot

Post by Robotnik » Wed May 24, 2017 9:16 pm

I've sorted it out now.
I measured the voltage at the battery, it was varying between 16v at idle and about 17.5v at 4000 revs. that is overcharging.

I unplugged and removed the voltage rectifier then with my meter I measured each of the three spade connectors which would usually have the white generator wires connected to them when it is plugged in, If you ever do this yourself ignore the fourth red wire connector, that is the output to the battery positive.

With my meter set on the diode tester I attached the red probe to the heatsink-negative, the results were .521, .517, and .520, all good.
Image

I then reversed the probes and performed the same test with the black probe connected to heatsink negative, the results this time were No reading, No reading and 1.039, that odd one is an indication that there is a faulty diode.
Image

I whipped the regulator off my spares bike and it tested OK so I've popped it onto my road bike for the time being, the battery voltage at idle is now 14.0v and the voltage at 4000rpm is 14.2, white wires and regulator get quite warm but nowhere near as hot as they did.

I have a 5 terminal V-Reg on the way, they are supposed to be much improved over the 4 terminal type so I'm going to convert it over when that arrives, easy to do as the extra terminal is just a negative which gets grounded to the frame.
Neil

Evilchicken0
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Re: Regulator rectifier wires are getting very hot

Post by Evilchicken0 » Wed May 24, 2017 10:04 pm

Well done :geek:


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