Motor Lead Pigtail Splicing of a 4000V Motor

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hv splices

hv splices

kkaragory said:
The theory behind the high voltage splice...

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The procedure that you allude to seems to be more in line for 12 kV and above; have you made many 4 kV connections the way that you described?
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About a dozen I built them out like a 13kv stress cone. 3m splicing tape i believe is rated to 69kv. Do not take a 4kv cable lightly it can be very dangerous. I used to work in a large federal research laboratory where they did cutting edge of science work. While I was there I recieved a bulletin about an electrician working for a federal lab. He aparently was troubleshooting a 2400v motor starter the only tester he had with him was a fluke 77 multimeter which was rated only to 1kv. The electrician presumed that the meter would read over range when he applied the leads. what happened in fact was the entire tester including the leads vaporized in his hands. The ionized air created a phase to phase short which lead to an arc blast which killed him
 
About a dozen I built them out like a 13kv stress cone. ...

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Were they shielded 4 kV or unshielded 4 kV? Or both? Why did you decided to follow the 13 kV stress cone avenue?
 
kkaragory said:
About a dozen I built them out like a 13kv stress cone. ...

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Were they shielded 4 kV or unshielded 4 kV? Or both? Why did you decided to follow the 13 kV stress cone avenue?
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Both because that was what my boss asked me to do at the time. and the drawings from the factory did not match the application we were doing. his license his customer his insurance his supervision what do you want me to do I am just an installer back then anyway as long as I didnt think it would cause anyone to get hurt I would follow supervision. Whenever they would ask me to do something that could hurt someone I would refuse tactfully.
 
I apologize for being so terse in my post. However, I am not new to this forum. I know how threads can "get away" and end up being about everything else but the question that was asked.
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You do not always get that choice, threads have a way of getting off topic, best in IMO to just ask you question and await what ever happens, there are some very knowledgeable folks on this list if the answer exist you'll get it and if the thread morphs so be it, I do not think anyone was ever hurt physically or emotionally by this morphing and it has resulted in some very interesting topics.
 
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kkaragory said:
If you want the best connection, why do you want a tape connection?

I have always had a print for the termination or splice that I was making giving exact dimensions of the tape buildup and length of stress cones and splices.

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The choice is not up to me. However, I still want to ensure that we are making correct connections.

I have this bad feeling that we are not taking into account partial discharge/ionization of the air at 4000V when taping our connections.

This is an engineering forum so I want to know why instructions are what they are...

I have found through experience that there are far too many electricians and engineers that blindly follow instructions without really understanding all the factors involved in whatever construction they are attempting to accomplish. I think grounding/bonding is an excellent example of this blind faith in whatever the schematics say.

That is what I thought this site was all about... finding the truth and debunking the myths behind our craft; so as to make safer, more reliable electrical installations.
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I just looked at a termination of 2400v shielded cable where the copper tape was removed but the semi-con was left in place. the tracking was teriffic and resulted in a lot of smoke and damage to the phase conductors.
point being the installer overlooked the legend that states semi-conducting, remove when splicing or terminating. once everything is cleaned up and the cable spare is pulled into the enclosure the youngest person with no prior experience will carefully prep the cable and apply the termination. having seen the damage he will be diligent in following the instructions. He will also ask questions for further understanding.
 
He will also ask questions for further understanding.

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Ask questions of whom???
 
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