Farm Equipment - 57 wd45 light switch resister

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57 wd45 light switch resister

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Topic: 57 wd45 light switch resister

Posted By: indianabevel
Subject: 57 wd45 light switch resister
Date Posted: 24 May 2011 at 8:25am

Hi Got a light switch from yesturdays tractor, my problem is lights work put resister gets supper hot and will burn up. redid some of the old wires but put back correctly. Why is resister getting hot. would it be best to replace cut out on generater with a regulator.
Steve

Replies:

Posted By: Steve in NJ
Date Posted: 24 May 2011 at 10:18am

One of the biggest problems that that aftermarket switch has according to a lot of my customer's is it doesn't fit well in some of the OEM AC Ammeter boxes. Make sure one of the hot leads isn't grounding on the inside of the box causing a dead short and the resistor to smoke along with the harness. We rebuild the OEM Delco round switch and have a exchange program on them. HTH

mailto:Steve@B&B - Steve@B&B

Posted By: indianabevel
Date Posted: 24 May 2011 at 10:46am

Hi steve, I was told to look for a steve with B&B. Your known world wide I guess. I spoke with yesturday tractors they said they are somewhat aware of the resistor getting hot, and said to run it with the lights on to pull some of the juice. So back to the problem, I don't have a positive wire grounded in the box, it is a bad fitting switch and is very close to the box. I no longer have the old switch Might I get one from you. I was also told to take the cutoff off and put a regulator on to bypass the resistor. Lastly with the wire cut from the hot resistor my electical dude disconnected the positive ground cable and the tractor died. Will it not run without the battery connected.
Thanks Steve

Posted By: jtheise4
Date Posted: 24 May 2011 at 10:52am

Any resistance device becomes hot as current passes through it. If your resistor is burning up, you are passing more current through the resistor than it can handle. All resistors have a power rating. P = voltage * current. You either need to increase the power rating of the resistor or decrease the amount of current draw (by reducing the number of lights on the circuit).

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1958 D14

Posted By: indianabevel
Date Posted: 24 May 2011 at 11:08am

well I have 4 light that turn on two front one rear plus the little fender tail light. I notice that with the lights off the meter needle flutters to the far plus charge side, with lights on it stops fluttering and goes to the negative charge side.
Steve

Posted By: Chalmersbob
Date Posted: 24 May 2011 at 9:51pm

the resistor has nothing to do with the lights. It is there to cause the genny to charge at a low rate, 3 amps. If you short the "field" connection on the genny to ground, it will charge at full capacity and burn up the genny if done too long. the resistor is used to reduce this charge rate. The light switch, in the "in" position allows the genny to charge at 3 amps. When the light switch is pulled to the 1st position, the lights will come on and the genny will charge at 3 amps. Pull the light switch out to the next position and it will cause the genny to charge at 10+ amps. This you only want to do for a short time and only when the battery charge is low. Bob

Posted By: Tedin NE-OH
Date Posted: 24 May 2011 at 9:56pm

I think you have a bad switch which puts voltage on the resistor.

Posted By: Chalmersbob
Date Posted: 24 May 2011 at 10:00pm

are you sure that you have it wired right?

Bob

Posted By: Chalmersbob
Date Posted: 24 May 2011 at 10:07pm

If you have a distributor on your tractor, it must have power it run, battery must be connected.

Does this light switch have a fuse on it? The fuse is for the light circuit and should

be wired to the amp meter. The wire from the Field terminal on the genny would connect to the resistor and the other end of the resistor is connected to ground (metal tractor frame). Bob