DC Motor Wires: Current Flow With/Without Insulation

AI Thread Summary
In a DC motor, insulation on copper wire is crucial for proper current flow and magnetic effects. Without insulation, adjacent wire turns could short-circuit, preventing effective current flow through the motor. The current would take available paths, potentially leading to inefficient operation. Motors typically use insulated wire, often enameled, to ensure that current flows correctly through the intended loops. Understanding the importance of insulation is essential for building a functional DC motor.
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One thing bothers me...

If we have a wire with NO insulation, and we make a loop like in these 2 examples. Connect those ends to battery. Current runs from + to -. Now, will the current behave like in A or in B(no insulation).

I know that with insulation, current will go in loops like A, but will it go in the same way without insulation?

I am trying to build an DC motor and i found all over net that they use copper wire, stripped.

Thx
 
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Motors never use bare copper wire except where it is stripped at the ends to make connections. The rest of the wire is always insulated, usually with a thin layer of paint-like enamel or a similar substance.

If bare wire was used, then turns next to each other could short together and current would not flow through the many turns and then the turns of wire would not produce the necessary magnetic effects to make the motor work.

To answer your question, the current would take whatever path was available to it depending on which wires were able to touch each other. So, you might get some current going in loops and some just going directly between turns of wire where they touched.
 
Google "enameled magnet wire". Determine correct wire gauge depending on current; e.g., 20 Gauge, 1.39 amps max. . See second from last column in http://amasci.com/tesla/wire1.html

Bob S
 
vk6kro said:
Motors never use bare copper wire except where it is stripped at the ends to make connections. The rest of the wire is always insulated, usually with a thin layer of paint-like enamel or a similar substance.

If bare wire was used, then turns next to each other could short together and current would not flow through the many turns and then the turns of wire would not produce the necessary magnetic effects to make the motor work.

To answer your question, the current would take whatever path was available to it depending on which wires were able to touch each other. So, you might get some current going in loops and some just going directly between turns of wire where they touched.

Yea thanks, didn't know that, looked stripped so it bugged me. (: thanks
 
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Certainly the current will go in the direction of B. Because no loop is created by insulation.
 
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