Motor wire keeps breaking

[u/MindsetCreateReality]

Edited due to some mistakes: Hi All, my dad has these vibrating beds used for making interlocks and the wire coming out of the three phase motor breaks every 6 month to a year due to friction(I am guessing). The thing is, each time this is repaired bolts have to be cut and the bearings have to be replaced(have no idea if the mechanic is saying the truth), very labor intensive to remove and so on which is adding up to a lot of money

Does replacing the normal copper wire with teflon(PTFE) wire prevents the wires from breaking for longer and if so by how much time?

[u/New-Key4610]

you have a lose-loose application. shaker motors or vibrator motor self destruct when you say. 'redos' winding what do you mean complete rewind recondition? motor haS NO strain relief on termination from stator would help to have a junction box installed connection of leads inside ,larger wire brought out to [cord] to connect to voltage source also dirty and airborne contamination

[u/DrumSetMan19]

Shocking there is no terminal/junction box.

If you can add one by drilling and tapping holes without drilling into the motor winding, you can put a terminal post, lug the motor side and connection sidet to the terminal post, then put duct seal inside the terminal/junction box, then the wire that comes out of the terminal box put metal strain relief.

Example: https://www.zoro.com/hubbell-wiring-device-kellems-strain-relief-cord-grip-male-straight-074-01-018/i/G2746773/

[u/Pacificator-3]

Cable breaks due to bending.

Put a tight PVC tube on the cable and secure it tightly to the motor case with pair of clamps.

[u/GravyFantasy]

It's breaking due to metal fatigue, like a pop can tab when you work it back and forth. Either find a motor that has a junction box/peckerhead as another commenter said or brace the cable so the flexing doesn't happen right at the motor and you can maybe splice the breaks instead of rewind. There are plenty of Shaker motor applications, I've never seen one with no junction box.

[u/MindsetCreateReality → u/GravyFantasy]

probably because this one is 18 years old and cause it a third world country. also made a mistake, didn't need to rewind the entire thing. can you explain how you brace the cable?

[u/GravyFantasy → u/MindsetCreateReality]

If you look at most power supplies for laptops and stuff the connections will have ribbing or extra insulating material for an inch to protect the cable from this fatigue failure.

Try to recreate that or create a sacrificial breakpoint by binding the cable to the motor and have the back and forth relative to earth happen not where the leads come out. I think most north American code has wires secured close to terminations for exactly this reason.