Insulated vs uninsulated wire in electromagnet

AI Thread Summary
In an electromagnet with non-touching coil windings, the choice between insulated and bare wire primarily affects thermal and electrical properties rather than magnetic strength. Insulated wire provides thermal insulation, potentially reducing heat loss, while bare wire allows for better heat dissipation, enabling higher current and potentially a stronger magnetic field. The discussion highlights that at low voltages, like 1.5 V, the difference in magnetic strength due to insulation is likely negligible unless the insulation has unusual magnetic properties. Concerns about parasitic capacitance arise mainly in high-voltage scenarios, which are not applicable here. Overall, the consensus leans towards minimal impact on magnet strength from the type of wire insulation used.
mortega
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Hello!

My first post at Physics Forums!

Nice to meet you!

In an electromagnet, where the coil windings are not touching themselves (the coil is not touching itself), is there any difference on the magnet strength created depending on whether the wire is insulated or not (bare wire)? If the coil windings were touching I would understand that the current would just short cut kind of in a straight line over the coil but in this case they are not. It will be only a few windings and they are not touching (a relatively weak magnet). But would it make a difference in this case if the wire was bare or insulated?

Added comment: it is insulation between the core (iron) and the coil itself.

Thanks.
 
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I can't see why unless the insulator has some weird magnetic properties. If you were talking about insulated windings within the coil and a high voltage you can get parasitic capacitance where some impedance is produced from the dielectric response of the insulator in between windings at different potentials. Between the coil and the magnets ? Doubt it.
 
mikeph said:
I can't see why unless the insulator has some weird magnetic properties. If you were talking about insulated windings within the coil and a high voltage you can get parasitic capacitance where some impedance is produced from the dielectric response of the insulator in between windings at different potentials. Between the coil and the magnets ? Doubt it.

It's low voltage, like 1.5 V. Not much more than 200 V at least.
Thanks for answer! I too would believe it has no noticeable difference, although I am not too sure.

In case others know of any difference it would be interesting to hear.
 
The insulation would act as thermal insulation as well as electrical insulation. If you use bare wire it will reject more heat and allow you to use higher current, which would allow you to make a stronger field. Not sure how relevant that would be to your application.
 
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