i started keeping a company bought digital camera in my service truck and many times it has been a very useful tool and saved many arguements! also very useful to discribe equipment parts and warentee problems-- like they say "a picture is worth a thousand words" ! one of my most useful issues with it was a million+ dollar fire job that we were called in on at a college. there was a contractor installing a job that we were underbid on. the switchgear was 1600 amp-480 volt square d, and they were trying to identify an unused feeder and had the switchboard cover and splash shield off. the contractor himself was there and decided to use his cell phone to communicate with the guy on the other end of the cables in another building. so he calls the guy up and tells him to stand clear because he is going to energize this breaker to make it easier to identify. now the feeder breaker is 1200 amp and takes two hands to close-so he set his cell phone down------"on another breaker" in the open switchboard. with two hands he closes the 1200 amp breaker and, of course, without the splash shield, all the breakers jump and he see's his cell phone bouncing back and falls into the exposed busing ! giant explosion instantly ! fire ball smacks him in the face and luckily he falls back out of the room. the explosions continued for 20 minutes !!!???? he was burned and sent to the hospital.
the college called us and we were close by. armed with my camera we waited for the fire department to evacuate the smoke and allow us into the electric room. as i took pictures, i was trying to figure out why there was so much damage. the vault was behind the switchgear and the service feeders-like 4-4inch with 500mcm cu burnt off in the rigid nipple as it came through the wall???? the buses in the switchboard were totally melted??? why didn't a fuse blow?????
i talked to the firemen and one of them told me the power company's primary jacks were on fire as they pulled up to the building ??? then the power company was threr and they opened up the vault and i went in armed with my camera---- and as i looked it dawned on me the vault was wired wrong ! the neutrals were made up to the vault's ground bus and not connected to the primary transformer's neutral. the vault's ground bus (with all the customer neutrals connected) had only one #4/0 cu conductor running to the vault's ground loop. this wire was blown in half about a foot from the ground bus connection. this is why there was so much damage -- without a path back to the source neutral, the overloads were never cleared ! the vault saw the short circuit as a phase to phase load.
the following morning, the contractor showed up and told me the story about how stupid he felt about setting his cell phone inside an energized panel--and as he told me the story he looked down and on the floor in front of the panel was a small molted item that used to be his cell phone--the battery made it through the explosion! i had already had square d manufacturing the necessary switchgear on a priority one order, but with the school's permision, offered to let hit repair his own mess! i made the necessary calls for him to take over the job and we left !
months later i get called from an attorney representing square d -- this contractor is sueing square d for faulty equipment-blaming the 1200 amp breaker ! he seemed to have forgotten the cell phone issue ! this kind of rubbed me the wrong way !!! i got on my computer and brought up the pictures i had taken the day of the fire. and you know how you can blowup a photo on a computer--sure enough you could actually see that that little rectangular piece of molten metal was a battery out of a cell phone--right were it had fallen after creating the problem. they came to my office for copies of the photos.
ps: the real kicker was after i had shown the power company guys their wiring problem---the following morning i went into the vault and during the night they had re-wired the ground bus with six 500 mcm cu back to the primary transformer. and when i questioned them--they said "you must be mistaken - thats the way the vault was originally wired" -- now the burn mark was still on the wall where the 4/0 cu had blown apart !! and i had the photos from the day before with that same burn mark proving my story !
sorry thing is "NOBODY LEARNED FROM THEIR MISTAKES IN THIS INCIDENT"! NOT THE POWER COMPANY --NOT THE CONTRACTOR --AND NOT THE COLLEGE FOR HIRING AN INCOMPITENT CONTRACTOR!