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What wire for inside electric motor?

auswelder

Plastic
Joined
May 5, 2018
I have an old 3 phase motor here, some of the wiring inside the motor that ends up coming into the motor terminal box is damaged and I would like to replace it.

Was just wondering what type of wiring needs to be used, i'm guessing it would need to be suitable for higher temperatures.

Thanks
 
It's called "magnet wire" and is used by motor rewind shops, but is not easy to find outside of that industry. You would need to know the level of insulation (voltage) in your existing motor, as well as the temperature rating. The temperature rating is typically indicated as a code letter on the motor nameplate, but the voltage level is not typically shown.

That said, if you are thinking in terms of splicing onto the existing windings to affect a repair, that's not as simple as you might think.
 
I think the OP is thinking about the lead wire between the magnet wire and the J-box. Just about any 105C stranded lead wire would do. The wire with the nylon jacket will give an additional protection from abrasion.

Tom
 
XLPE Cross-linked Polyethylene, Temperature Rating: 125°C
UL 3173, UL 3195, UL 3196 is appliance wiring material suitable for internal wiring of appliances, coil leads, switchboard panels, lead wire for mercury lighting ballasts and power operated dispensing units where exposed to gasoline vapors, also as class B motor lead wire.

Sample page: UL 3173 UL 3195 UL 3196 Hook Up Wire (SIS) | AWCwire.com | Distributor

SRML Silicone Rubber Motor Lead With Fiberglass Cover
Ideally suited for use in areas where temperatures range from -90° C to 200° C. Can be used near ranges, furnaces, or other types of heating elements. Even soldering heat won't cause the insulation to melt or peel. Can be used where very low temperatures are a factor and won't harden or crack, even when flexed after lengthy aging and exposure.

Sample page: SRML On Standard Wire & Cable Co.

SAF Ω
 
So is it basically the same wire you would find in an extension lead?

Sent from my SM-G935F using Tapatalk
 
So is it basically the same wire you would find in an extension lead?

Sent from my SM-G935F using Tapatalk

Motors get hot, so the wire needs to be rated for higher temperatures than the average extension cord. The exact rating needed depends on the temperature class of the motor, but there is no harm in using wire rated higher than the motor temperature
 
This thread made me curious as I frequently put new leads in a motor. So I did an experiment, I took a piece of THHN and a piece of XLPVC. Hit them with a heat gun ( 900 degrees ) The THHN cooked, while there was no effect on the XLPVC. So there you have it.
 
You will have to unbundle wiring inside that has been coated with varnish. That is the way to find the splices for the wires. Probably will have to unbundle some of the ties. As long as no damage occurs then no big deal.
 








 
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