VFD Safety

[piffer]

Has anybody experienced a drive "going plasma?" I was at an equipment startup recently and a brand new 200 HP drive toasted after ~20 minutes of operation. The drive rep. said it "went plasma." It was very fortunate that the panel door was closed. Minutes earlier, technicians were inside the cabinet taking measurements.
I now know that I won't go near an open drive without a full-face shield (protective eye wear isn't enough). Any similar experiences out there? I'm not an electrical guy, so excuse my lingo.

 

[busbar]

NFPA seems to be putting it into practice.

http://www.nfpa.org/PDF/70E-03-preprint.pdf

Nota Bene,
Annex A, Limits of Approach
Annex B, Sample Calculations for Flash Boundaries
Annex C, Sample Calculation of Incident Energy and Flash Protection Boundaries
Annex M, Hazards associated with Power Electronic Equipment

 

[d23]

piffer

Several years ago I went to Argentina to install some drives. Two of the drives blew up due to some inverter software problems. My customer referred to this as the “BOOM TEST”….

We now install micro switches on our drives to prevent it from operating when the door is open. You may want to do this with yours. The “BOOM TEST” is no fun.

David

 

[jbartos]

Suggestion: Visit

http://www.bussmann.com/services/training/docs/Pres10-Arc Flash Boundaries & Design-Script 2-02.pdf

for Flash Boundaries

http://www.bussmann.com/services/training/docs/59

for Bussmann slides that include, beside NFPA 70E, Occupational Safety and Health Standards for General Industry, 29 CFR Part 1910, dated February 1, 1999

 

[peebee]

I know of a drive that had a cheapo rotary disconnect switch in it, the switch went big while the tech was programming it. The switch shaft blew over his head (luckily) and embedded itself in the block wall across the aisle. He ended up with no eyebrows and what looked like a bad sunburn.