vfd noise problems???

[mike_kilroy]

I dont want to hijack the main idea of this thread. I would like to hear how the OP tests went and if the problem is solved and how it was ultimately solved. But, sure, needs a big drill; these machine tool rebuilders don't have little 3/8" small drills - they have plenty of BIG tools.

 

[Jraef]

Wouldn't you need a fairly large chuck to accommodate four #6 conductors?

For larger cables we would put them into a Kellems pulling grip and tape the he'll out of it so the cables don't slip at first before the cage tightens. Then we put a 1/2" eye bolt on the pulling eye and put the threaded end of the bolt into the drill chuck. You want to use a 1/2" drill motor, 3/8" are too fast and generally too weak. We later just welded a 1/2" hex shaft onto the Kellems grip.

 

[Besoeker]

For larger cables we would put them into a Kellems pulling grip and tape the he'll out of it so the cables don't slip at first before the cage tightens. Then we put a 1/2" eye bolt on the pulling eye and put the threaded end of the bolt into the drill chuck. You want to use a 1/2" drill motor, 3/8" are too fast and generally too weak. We later just welded a 1/2" hex shaft onto the Kellems grip.

Interesting technique.
We do use twisted pairs mostly for the gate cathode wires for SCRs.

And we do twist them with a drill. But they are small - 1mm²
The other factor is the the twisted pair is reduced in length from the original conductors. Our workshop foreman gets it made up in fairly long measures that get cut to length after twisting to suit the application.

 

[Rsteenson]

Problem solved! After the dryer tech claimed the gas system was working properly and INSISTED it was an electrical problem, me and an HVAC tech found one of the two regulators on the dryer was faulty and creating back pressure on a solenoid valve, which in turn would not open intermittently. So after alot of screwing around running new 2" rigid conduit, playing with carrier frequencies, isolating and re-routing motor leads, installing load reactor, we found it was NOT related to vfd noise! Oh well, Im just glad its running! Thanks for the advice and help!