High Voltage Power Supplies
Hi all,
Looking for opinion and general thoughts on allowing workers to permanently occupy an area that contains high voltage power supplies. Workers have cobbled together a workbench within the HV space to work on capacitor modules and igbt’s that come from damaged power supplies. They have a backlog of work to do, so they often spend between 4-5 hours per shift working at this desk/workbench inside the high voltage space. These are qualified electrical workers that observe appropriate distances, clearances and maintain egress paths. Is anyone aware of any regulations that might prohibit continual occupation of this type of HV space?
Comments (14)
What do you consider as "high voltage"?
Generally speaking, as long as you adhere to any PPE requirements, approach distances (e.g., limited approach, restricted approach, arc flash), and other safe work practices, you're ok.
I differ a bit than the "Doc"! Why tempt fate? Might be safe but it is the safest? I do agree the risks are low, so if it the convenience outweighs the risk you are OK but not my preference. What if a lazy contractor opens up the panels and an new employee wanders to close? If you have other areas use them.
I am probably way to over cautious on electricity! In my end of manufacturing one of the few areas someone could easily get killed quickly! In 50 years in the business have not lost anyone to the Grimm Reaper! Came all too close a couple times. The first and some 45 years ago I was the fist one to get to one of our UAW journeymen electricians (some of the best industrial electricians you will ever see) in the foundry. Bobby was blown off a substation after taking over 12,000 volts and God only knows how many amps! When I got to him I could not recognize him, he was a friend of mine, but where his head was, there was a smoldering basketball! And the smells haunts me to this day! (let's just say I get sick around charred meat to this day!). His leg was broken, as his leg was completely behind him, and the right femur was sticking out of his pants like a spear! He was in the University of Michigan burn unit for a year, and lost his right eye, ear, and half his nose! He lost all the pigment on the right side of his head, he was a black man. He died 5 years later at 38 leaving 5 kids, due to a stroke from blood clots, that almost certainly (but not proven) a result of his surgeries and injuries. Maybe I did lose somebody after all!
So yes I am overly cautious about electricity! But one "Bobby" a career is too much!
It is pretty common to have work benches in mechanical spaces or equipment rooms.
The thing to look out for is combustible material storage.
IFC says: 315.3.3 Equipment rooms. Combustible material shall not be stored in boiler rooms, mechanical rooms, electrical equipment rooms or in fire command centers as specified in IFC Section 508.1.5.
I’m pretty certain that the NFPA guidelines are pretty strict about this and say that no storage can take place inside an MCC room. That includes tables chairs tool it’s gotta be empty and controled. I believe the reasoning behind this is that our flashes are extremely powerful, and not only do not want it to throw things, but you don’t want to be thrown into them.