Control/Dimming Questions about 3 phase - 1 phase load

[icewolf08]

FYI NEVER EVER RUN A MOVER OFF OF DELTA POWER. THEY GET REALLY MAD AND LET OUT THE MAGIC SMOKE. I will try to post pics as to what happens. They want two legs of 120, not a leg of 208. Theoretically i guess you should be ok going between one leg of 120 and one of 208, but i really dont want to try it. Delta does make motors really happy though.

Even electronic ballast units? Most of the electronic ballast units are rated from 90V-240V without rewiring, so it would seem to me that single phase 208 (wild leg delta) shouldn't really make a difference. I certainly could see it being an issue with magnetic ballasts, or any that are not auto sensing.

 

[JD]

Not big on Delta loading a Wye source. (EX- wiring a bunch of movers across the 208 legs of a Wye feed.) Two things come to mind, both due to the use of fused disconnects: One, if a leg opens, you end up with a random bunch of movers (2/3) operating on whatever voltage they have fought out between themselves! Two, you now have a dead leg that isn't quite dead. I know, I know, how often does a fused disconnect open? I've actually had it happen twice, and neither time due to a blow!

Some years ago, there was a crazy fuse manufacturer that made cartridge fuses that had replaceable links! You can spot them because the end caps unscrew. In both cases, the links were not installed correctly, and opened up at the screw. Haven't seen any in years and hope they still aren't making them! (think the last time was 82')

EDIT: Oh no! They are still out there!!!!

EDIT:
Ahh.. don't mean to imply that Buss is a crazy manufacturer... Not sure they were Buss.. OK, I'd better stop now....

 

[gordonmcleod]

Yes replaceable link type fuses are still made and iff used correctly were very good typically they were in vdery large sizes only

 

[TimMiller]

the lights that blew up were magnetic studio colors. But in studio colors you still have a electronic auto switching powersupply that runs the electronics. The logic boards of all of the units now have holes blown in them