Rewiring motor - what gauge wire?

[amateur_24]

Hi
I tested my CNC spindle with the speed cranked all the way up. At the time it didn't occur to me it could spin out of control. Silly I know. We live and learn! Now the insulation is damaged. You can see the copper wire.

Since I have damaged the insulation in multiple places and the wires aren't long enough, I thought I will rewire the motor. I have got the motor apart but am unsure what gauge wire it uses. The wire I have appears to be a little on the thin side.

I have attached an image of the wire to this post. Any help would be greatly appreciated

 

[rjenkinsgb]

Without something to give proportions, it could be any size?

eg. What is the outer diameter of the insulation?

 

[amateur_24]

Hi
I tested my CNC spindle with the speed cranked all the way up. At the time it didn't occur to me it could spin out of control. Silly I know. We live and learn! Now the insulation is damaged. You can see the copper wire.

Since I have damaged the insulation in multiple places and the damage is quite far up the wire. Also the wires aren't long enough so I thought I will rewire the motor. I have got the motor apart but am unsure what gauge wire it uses. The wire I have appears to be a little on the thin side.

I need to purchase the same gauge wire because of the pre drilled holes on the plastic mount which holds the carbon brushes.

I have attached an image of the wire to this post. Any help would be greatly appreciated

 

[alec_t]

If you have access to a micrometer you can measure the wire diameter, then use look-up tables (plenty on-line) to find the wire gauge.

 

[amateur_24]

Lol stupid. I should of thought of to measure it. I feel ridiculously stupid. It's 2.5mm outer diameter. It's 1.3mm inner diameter.

 

[MaxHeadRoom78]

That is not the main winding surely, it is normally enameled wire insulation.
Or is this the supply conductors to the windings ?

 

[amateur_24]

Sorry this is just for the supply into the motor. Not the windings. I wouldn't even attempt such a task. Just in case I burn the house down.

 

[MaxHeadRoom78]

The connecting wire should be THHN or equiv. and a gauge to suit the HP of the motor.

 

[amateur_24]

Thhn. Is silicone wire good enough? I struggling to find thhn cable in a size 17awg?

 

[MaxHeadRoom78]

Should be OK.

 

[rjenkinsgb]

Thhn. Is silicone wire good enough? I struggling to find thhn cable in a size 17awg?

I'd suggest sleeving silicone wire, or use conduit. It's excellent for flexibility and high temperatures, but not necessarily all that good for long term abrasion resistance in something that could be vibrating.

We use a lot of silicone coated fibreglass sleeving & PMA conduit for that type of thing.

Otherwise, I'd probably go with Tri-rated wire & sleeve / conduit or polyurethane insulated cable.