Bolt Switch stuck closed

[Brandon Loyd]

Hi all,
Customers 3000A fusible Square-D Bolt-Loc pressure switch blew a fuse (unknown reason) on "B Phase". They replaced the fuse, but then the switch wouldn't stay in the closed position (lots of charring and pitting on/near the contacts). They decided to make it stay closed by either installing a bolt through the contacts or overtightening the contacts, either way they did whatever it took to restore power. I was called to evaluate the situation and make recommendations.

I'm recommending they replace the switch but need my findings/recommendations in writing first. Other than not being able to open this switch for maintenance, testing, or disconnecting means (they can still de-energize it upstream), what other consequences (safety and code related) could I tell them may arise by leaving the switch in this condition? This is the main 120/208V normal power switchboard in a hospital, BTW.

Thanks in advance.

 

[jim dungar]

Hi all,
Customers 3000A fusible Square-D Bolt-Loc pressure switch blew a fuse (unknown reason) on "B Phase". They replaced the fuse, but then the switch wouldn't stay in the closed position (lots of charring and pitting on/near the contacts). They decided to make it stay closed by either installing a bolt through the contacts or overtightening the contacts, either way they did whatever it took to restore power. I was called to evaluate the situation and make recommendations.

I'm recommending they replace the switch but need my findings/recommendations in writing first. Other than not being able to open this switch for maintenance, testing, or disconnecting means (they can still de-energize it upstream), what other consequences (safety and code related) could I tell them may arise by leaving the switch in this condition? This is the main 120/208V normal power switchboard in a hospital, BTW.

Thanks in advance.

The NEC is about installing equipment, so it likely doesn't cover this situation. However, NFPA70E definitely, and both OSHA and the Joint Commission (JCAHO) likely, does not allow disregarding manufacturer operating and maintenance instruction and procedures.

 

[kwired]

I think it needs repaired by someone qualified to recondition it or replaced. Reconditioning likely means continuing with something makeshift while being repaired, something not normally given a blessing by safety standards. Purchase of already reconditioned unit if one is available maybe better option then waiting for yours to be repaired. Brand new - you possibly get better buy if you purchase the entire switchboard, panel, or whatever it is in vs just buying the switch itself - that is how they like to sell this kind of equipment.

 

[zog]

I'll skip over the OSHA violations of just replacing the fuse that blew for an unknown reason and reclosing the switch without further actions and the violations of over riding a protective device, and focus on the solutions.

First thing that comes to mind is the fuse door interlock, the door needs to be fully closed and the screws fully tightened or it will prevent the switch from closing. If that easy fix isn't the problem it is likely the operating mech that hasn't been properly maintained like these need to be. Probably not an easy on site fix but it's possible , have someone come out that is familiar with these. (I would recommend someone but your profile doesn't say where you are located).

If it can't be repaired on site find a rental switch, swap it out, send yours out for refurbishment, then swap them back out. Cheaper route than buying a replacement.

 

[Brandon Loyd]

Thanks for the input guys. Does anyone know which articles in NFPA70E this condition would violate? I need to be able to reference specific violations.