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Why aren't the coils in electric motors insulated?

by Xyius
Tags: coils, electric, insulated, motors
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Xyius
#1
Feb29-12, 07:56 PM
P: 437
In all the electric motors I have taken apart, the coils on the armature have never been insulated. This has always confused me because, how could the coil make a sufficient magnetic field if it shorts out to the adjacent wires from lack of insulation?
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DaveC426913
#2
Feb29-12, 08:18 PM
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Are you sure they're not coated in a thin layer of clear sheathing?
Xyius
#3
Feb29-12, 08:19 PM
P: 437
Quote Quote by DaveC426913 View Post
Are you sure they're not coated in a thin layer of clear sheathing?
I have suspected that but I do not know for sure. I was wondering if anyone else could confirm. :]

Hassan2
#4
Feb29-12, 08:46 PM
P: 409
Why aren't the coils in electric motors insulated?

They are insulated with a think transparent layer of insulator.
TurtleMeister
#5
Feb29-12, 09:02 PM
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Quote Quote by Hassan2 View Post
They are insulated with a think transparent layer of insulator.
No, I don't think it's transparent.

Magnet wire is coated with a thin layer of enamel. The color is usually gold, making it appear similar to bare copper. It also comes in other colors, such as red and green.
Xyius
#6
Feb29-12, 09:14 PM
P: 437
Cool thanks guys!
Hassan2
#7
Feb29-12, 09:21 PM
P: 409
Quote Quote by TurtleMeister View Post
No, I don't think it's transparent.

Magnet wire is coated with a thin layer of enamel. The color is usually gold, making it appear similar to bare copper. It also comes in other colors, such as red and green.
Thanks a lot. Do you know how to remove the insulation before soldering? Or is it removed by the heat while soldering? I usually use flame to remove the insulation first. Sometimes just scratching them by a knife! I wonder if there was a more efficient way.
DaveC426913
#8
Feb29-12, 09:24 PM
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Quote Quote by Hassan2 View Post
Thanks a lot. Do you know how to remove the insulation before soldering? Or is it removed by the heat while soldering? I usually use flame to remove the insulation first. Sometimes just scratching them by a knife! I wonder if there was a more efficient way.
Wire strippers are the correct way.
TurtleMeister
#9
Feb29-12, 09:40 PM
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Quote Quote by Hassan2 View Post
Thanks a lot. Do you know how to remove the insulation before soldering? Or is it removed by the heat while soldering? I usually use flame to remove the insulation first. Sometimes just scratching them by a knife! I wonder if there was a more efficient way.
Yes, there is a more efficient way. You can buy a machine that is designed for removing the insulation. However, the price is probably too high for the hobbyest. I used such a machine many years ago when I worked for a motor manufacturer. At home I usually just lay it on a flat hard surface and scrape it with a sharp knife. I've never had much luck with using wire strippers on magnet wire.
Pengwuino
#10
Feb29-12, 09:41 PM
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Quote Quote by DaveC426913 View Post
Wire strippers are the correct way.
How do you use wire strippers to take off such a thing layer?
DaveC426913
#11
Feb29-12, 09:45 PM
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Quote Quote by Pengwuino View Post
How do you use wire strippers to take off such a thing layer?
Mm. Good point. It's not designed to be stripped like regular electrical wire, is it? It won't just slide off.
AlephZero
#12
Feb29-12, 11:27 PM
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P: 7,172
Modern "enamelled" wire usually has a plastic coating that will burn off cleanly during soldering. The wire in old motors etc uses "real" enamel which needs to be scraped off with a knife blade or fine sandpaper.

There are electrically powered tools available to do this on an "industrial" scale.
Delta Kilo
#13
Mar1-12, 07:35 AM
P: 273
Apparently some types of enamel could be stripped by placing the wire on aspirin tablet and heating with a soldering iron (or so the urban legend says). Never tried it myself though.


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