Why aren't the coils in electric motors insulated?

In summary: Mm. Good point. It's not designed to be stripped like regular electrical wire, is it? It won't just slide off.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.
  • #1
Xyius
508
4
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?
 
Physics news on Phys.org
  • #2
Are you sure they're not coated in a thin layer of clear sheathing?
 
  • Like
Likes russ_watters
  • #3
DaveC426913 said:
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. :]
 
  • #4
They are insulated with a thin transparent layer of insulator.
 
Last edited:
  • Like
Likes russ_watters and Delta2
  • #5
Hassan2 said:
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.
 
  • #6
Cool thanks guys!
 
  • #7
TurtleMeister said:
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.
 
  • #8
Hassan2 said:
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.
 
  • #9
Hassan2 said:
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.
 
  • #10
DaveC426913 said:
Wire strippers are the correct way.

How do you use wire strippers to take off such a thing layer?
 
  • #11
Pengwuino said:
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.
 
  • #12
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.
 
  • #13
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.
 
  • #14
Use a pocket knife and scrap off the ends like you would to strip off plastic insulation.
 

1. Why aren't the coils in electric motors insulated?

The coils in electric motors are not insulated because the insulation would increase the distance between the coils, reducing the efficiency of the motor. Insulation also adds weight to the motor, which can impact its performance and speed. In addition, the insulation material can also deteriorate over time, leading to potential breakdowns of the motor.

2. Will the lack of insulation cause any safety hazards?

No, the lack of insulation in electric motors does not pose any safety hazards. The coils are designed to be in close proximity to each other and operate at high temperatures. The materials used in the coils are also designed to withstand these high temperatures without any risk of electric shock or fire hazards.

3. Can insulation be added to the coils after the motor is assembled?

In some cases, it is possible to add insulation to the coils of an electric motor after it has been assembled. However, this process can be difficult and may require disassembling and reassembling the motor. It is generally not recommended to add insulation to an already functioning motor, as it can impact its performance and may not be cost-effective.

4. Are there any benefits to insulating the coils in electric motors?

In certain cases, insulating the coils in electric motors can provide benefits such as reducing electromagnetic interference and improving the lifespan of the motor. However, these benefits may not outweigh the potential drawbacks and added costs of insulation, and it ultimately depends on the specific application and requirements of the motor.

5. Is it possible to use insulated coils in electric motors?

Yes, it is possible to use insulated coils in electric motors. However, this is not a common practice due to the reasons mentioned earlier - it can decrease efficiency, add weight, and potentially cause breakdowns. In some specialized applications, such as in high-voltage motors, insulated coils may be necessary for safety reasons.

Similar threads

Replies
8
Views
17K
Replies
5
Views
1K
  • Electromagnetism
2
Replies
43
Views
1K
Replies
4
Views
1K
Replies
3
Views
779
Replies
27
Views
1K
  • Engineering and Comp Sci Homework Help
Replies
4
Views
686
Replies
8
Views
2K
  • Electromagnetism
Replies
8
Views
7K
  • DIY Projects
Replies
23
Views
2K
Back
Top