Author Topic: Isolating motor and lights  (Read 1120 times)


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Isolating motor and lights
« on: February 01, 2017, 09:15:55 PM »
Hello Group:

The Installation Instructions for the LM-2S state: "Be sure the motor and all lights are not connected to the chassis or frame. Isolating the motor and lights is likely to be necessary when converting non-DCC ready locomotives to use RailPro."

If I have a locomotive with a wooden floor, is it still necessary to isolate the motor?  How should the lights be isolated (or do they need to be isolated) if the body is metal, with a wooden floor?

Mike Sullivan


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Re: Isolating motor and lights
« Reply #1 on: February 01, 2017, 09:53:58 PM »
Hi Mike,

What isolation means is that current (track power) cannot flow to the motor or lights without going through the LM. In the olden days (and it's still prevalent as manufactures don't always update older models when doing re-runs) much of the time the chassis / frame on the locomotive was basically an electrical bus bar, the pickups on one side of the locomotive were connected directly to the frame and one side of the motor and lights (terminals that is) were connected to the frame as well. Athearn models from the blue box era were a good example of this system.

As your model has a wooden floor it's highly likely the motor and lights are isolated from the frame; wood is a very poor conductor of electricity.
If your still unsure, you can post us a photo of the models internals and we'll see if we can see anything different of potential pitfall.

- Tim


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Re: Isolating motor and lights
« Reply #2 on: February 02, 2017, 07:35:42 AM »
In very humid situations wood can become a high resistance conductor. Not a high probability it would be a problem but I would insulate just to be absolutely certain. A single layer of thin packing tape will work while not changing any critical dimensions. Use nylon screws if your current metals screws contact the wood.
« Last Edit: February 02, 2017, 09:32:37 AM by Alan »

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