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Mv motor T-lead insulation repair (?)

Mv motor T-lead insulation repair (?)

Mv motor T-lead insulation repair (?)

(OP)
Let's say you find that the T-lead insulation of an installed motor is damaged (at a point where if you cut it off and relugged, the lead would be too short).

The damage penetrates the insulation, but does NOT extend to the conductor.

Would you consider repairing the insulation using sleeving, tape etc ? (rather than sending motor to shop to unsoldering at the endwinding connection and install new leads)

What product would you use?

Attached are 2 examples
 

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(2B)+(2B)'  ?

RE: Mv motor T-lead insulation repair (?)

e-pete,
 Please disregard my previous post. The product that I linked to wasn't the one I was thinking of. I was thinking of something from the 3M EPS group of products. Try searching 3M EPS and see what you find - good luck.

Thanks  

RE: Mv motor T-lead insulation repair (?)

(OP)
Thanks Pete!

It says "designed to repair damaged cable jacketing".

It may work, but seems to fall short of being applied within the manufacturer's (3M's) written guidelines if we used it for insulation repair.

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(2B)+(2B)'  ?

RE: Mv motor T-lead insulation repair (?)

e-pete
  Your right, sorry about that, I should have made sure I was recommending the right thing. I remember that I used something from 3M many years ago to repair a motor lead in pretty much the same situation that you are in. I think that I may have found it (see link below). A few possible problems: From your picture it appears that the lead wire insulation is silicone and there just might be a compatibility issue (check with vendor). The kit is only rated for 8kv, based on the thickness of the insulation in your picture I'm wondering if the motor voltage may be higher than that. Of course you aren't going to be actually splicing the lead so you will have all the original insulation underlying the sleeve so it will probably be fine. Finally, one of the great things about silicone lead wire is it's flexibility and you'll certainly lose a lot of that in the area of the sleeve.
  

Thanks

RE: Mv motor T-lead insulation repair (?)

(OP)
That is the conclusion I was coming to. Splice kit seems to be closest match for this type repair, even though we're not doing a splice.

These examples are already resolved, although I'm looking forward to be able to have a good plan for the next one.

Example 1 was 13.8kv system.  Repair shop vendor resolved this condition by adding Raychem BBIT, although I'm not sure I am completely comfortable with this.   The BBIT is rated to reduce the clearance requirements between busbars, but there is still a requirement for clearance after it's installed which T-leads don't meet. Maybe common sense says the combination of BBIT and original insulation is up to the task, but tough to prove since neither individually would be capable (the original insulation not capable because it's damaged).   For one thing there may remain a void in the location of those nicks that is not completely filled.   I like the idea that the splice kit has a mastic which will tend to fill those type voids.  I'm pretty sure we can find 15kv splice kit if we need one.

Example 2 is 4kv motor.  We decided to send the motor to the repair shop to replace the leads.  
The location was where the T-lead passed out of the motor through a conduit fitting into the term box.  Several challenges made repair in-place infeasible.
1 – there is access only from one side.. to get to the other side would require substantial motor disassembly.
2 – It is a tight fit through the conduit fitting... not a lot of room to work.
3 -  This is a natural mechanical stress concentration location since the T-lead must bend down to meet up with the power leads once it enters the term box. This is related to the item you mentioned... lack of flexibility after repaired.
Even splice kit probably wouldn't have worked for this 2nd example due to limited access and mechanical stress /bending concerns.  

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(2B)+(2B)'  ?

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