An electrician was changing a triple pole mcb on a merlin gerin distribution board last month, doing it live as we all do and one of the busbars was loose and it dropped onto the one below as he took off the MCB. We heard the bang from 100 yards he came out of the shed completely white. the board was fed by a 100 amp supply.the earth bar is set back from the mains terminals so wont touch if unscrewed. if it was touching there would be a bloody big bang no screw left . a big hole in the bar and a ton of black carbon round it
- Thread starter steveo3002
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They always seem a bit behind the times with electrics. Their new stuff looks like the old 80/90s Square D stuff we did away with decades ago.
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One of the sparkies at Rover dropped a spanner into a live busbar chamber, he was known as "flash" for a few years after
dobbslc
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I know those old Melin Gerin boards only to well, my old boss was to tight to replace one in the new company building and that caused all sorts of trouble down the line
Even worse is we were an electrical contractors
Don't do what the installer did here, I say installer as I don't think he could have been an electrician. The wires were cut too short so he bent the wires so they went into the terminals when he pushed the switch over the back box. To help make sure the wires went in easier he took the screws out of the connection terminals. Some of the wiring in here has been pretty scary.
One of my old workmates had to get some details off an old slip ring motor we had that the insurers for some reason. It was operating but he thought it would be ok just to take the terminal cover off to get some details. The cover was full of presumably carbon dust from the brushes, the dust dropped onto the slip rings and a dirty big arc shot up and got him. He came out of the plant room with a smouldering burn on his hand and something similar on his foot. He was pretty lucky to be able to walk away from it, it was a big old motor to get a belt from.
Erie Fred
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What does you little plastic house panels have for interrupt ampacity ?
Erie Fred
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a few of us apprentices were standing around for a minute, not really noticing Tom the maint. man
was behind a group of multi spindle drill press's, they sort of formed a cubby hole behind them.
He dead shorted 575 vac, and the flash bounced off everywhere.....we frantically started calling out where is Tom ?
He emerged a few seconds later, quite shaken, and said "I need a cigarette".
was behind a group of multi spindle drill press's, they sort of formed a cubby hole behind them.
He dead shorted 575 vac, and the flash bounced off everywhere.....we frantically started calling out where is Tom ?
He emerged a few seconds later, quite shaken, and said "I need a cigarette".
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Domestic MCB's are normally 6kA and industrial are 10kA
Erie Fred
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"our" standard house panels & breakers are 10ka.
"They always seem a bit behind the times with electrics. Their new stuff looks like the old 80/90s Square D stuff we did away with decades ago."
I'll stick with the "old time" all metal panels, with bolted in the back bussbars, with snap on breakers thank you.
I don't care about the "look" of the panel, it's not flying down the road at 65 mph.
FWIW Leviton came out with a new line, even better features.
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northwest
Searching for the Holy Grail.........
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I try to steer clear of any electrics now. I am not sure what 240volts will do to my heart implant and I have no real desire to experiment. If I really must mess with them the mains are well and truly isolated first.
Onoff
In the land of the unfinished project I am King!
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40 years ago, on a roof as "the mate" with an older electrician. He said I could "change the contactor" whilst he watched. This btw is with zero experience and at that point just on the job training. All I remember was hitting a plant room wall and the guy saying "You were standing in front of me one minute....."
240/415? Could have been either. If the panel had been facing the other way I'd have been off the roof.
Had a 110VAC belt (very old kit's control voltage, not a centre tapped trannie), through a sweaty armpit once (sun's out / guns out). Not funny.
Training in safe isolation was a revelation.
240/415? Could have been either. If the panel had been facing the other way I'd have been off the roof.
Had a 110VAC belt (very old kit's control voltage, not a centre tapped trannie), through a sweaty armpit once (sun's out / guns out). Not funny.
Training in safe isolation was a revelation.
The_Yellow_Ardvark
https://www.death-clock.org/
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This is a repost of a good installation.
Monkey Harris
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plumbers electrics ..!
daleyd
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Dave-sparks
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They haven't been plastic for a few years now.
A standard consumer unit has 6kA devices and backed up by the standard service fuse is overall rated for 16kA.
16kA being the normal maximum limit for a domestic supply but in reality it rarely gets near the 6kA point.
Dave-sparks
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But what is the typical prospective fault current for a house supply there?
