Ash, what bottom left inside CU or below it outside of CU??
Log cabin burnt down
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The cert looks like the "internal" generic cert from the "easycert" software, tbh - suggesting the spark either didn`t want to, or couldn`t, use the pre-printed NIC ones.
Its interesting that the results, if indeed done through easycert, would have been flagged as suspect by the program - they were either ignored; or the muppet in question didn`t know what he was doing!
Its interesting that the results, if indeed done through easycert, would have been flagged as suspect by the program - they were either ignored; or the muppet in question didn`t know what he was doing!
Inside bottom left - sounds like they missed bus bar into bottom of main switch. Most CUs (that I fit) have main switch left hand side. I have a small inspection mirror for checking busbar is clamped properly by main switch / MCBs - comes in very handy.
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I still find it hard to believe that an "arcing busbar" can actually set fire to a (supposedly) inflamable CU enclosure.
A post mortem examination of the charred remains should prove if the busbar was clamped properly.
I still think it's VERY poor that the majority of main switches and MCB's are actually made such that it's possible to "miss" the cage clamp.
A post mortem examination of the charred remains should prove if the busbar was clamped properly.
I still think it's VERY poor that the majority of main switches and MCB's are actually made such that it's possible to "miss" the cage clamp.
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Seems strange to me to have two earthing systems and if I had had those loop readings on a TN system I would be thinking something is very wrong.
I can. I have seen quite a few overheated C/Units and was supprised how distorted and melted they had got. I try to always fit a metalclad board nowadays because everything is crap.
The enclosures are fire retardent, not fire proof, so will burn if something keeps pumping energy into them. The MCBs and main switches seem to be more fire retardent than the enclosures. There was a post some time ago on screfix, about a company who were involved in a CU that caught fire, and were being sued for negligence. As part of his defence, the sparky concerned went about testing enclosures for their fire-retardency. Now it had to be said some of his methods were a little unscientific, but the results were non the less quite revealing, with very few enclosures showing much sign of fire retardency when exposed to a naked flame. Some of you keen you tube users may still be able to find the video.
Thought it would be of interest to some....
I had one of our fire investigation/safety bods take a look at the pictures......
Seat of the fire is definately high up next to the bathroom/toilet door.
The way the burn scaling has gone up the wall & over the roof shows high temp was reached very quickly.
High level of sooting probably due to insulation & shows the heat was rolling along the roof dropping down the cupboard face from right to left.
Worktop looks to have laminate in early stages of ignition, most likely from molten insulation dropping down as the damage isnt across by the cu's location.
The open (diamond shaped) cutouts in the cable void look to have given a chimney effect to flame propagation, once it came through the cable entry hole & gave access to allow the flame to get external before burning through the roof (If you thought it was a waste of time/money & skipped putting the stuff in....you can now see why intumescent fillers are used).
Cause would go down as electrical
He added any advice/thoughts given are not binding & can not be used in any report as he has only seen photos.
I had one of our fire investigation/safety bods take a look at the pictures......
Seat of the fire is definately high up next to the bathroom/toilet door.
The way the burn scaling has gone up the wall & over the roof shows high temp was reached very quickly.
High level of sooting probably due to insulation & shows the heat was rolling along the roof dropping down the cupboard face from right to left.
Worktop looks to have laminate in early stages of ignition, most likely from molten insulation dropping down as the damage isnt across by the cu's location.
The open (diamond shaped) cutouts in the cable void look to have given a chimney effect to flame propagation, once it came through the cable entry hole & gave access to allow the flame to get external before burning through the roof (If you thought it was a waste of time/money & skipped putting the stuff in....you can now see why intumescent fillers are used).
Cause would go down as electrical
He added any advice/thoughts given are not binding & can not be used in any report as he has only seen photos.
Nicky Tesla
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Ze calculates as 230V / 0.6KA = 0.38ohms
Now the water heater on 10mm cable (for some reason when the method is C) is showing a R1R2 as 0.03, now adding that to Zs will not be anywhere near 1.22. And why on 32A and the cooker on 40A.
Also its not shown as a split board so are all those 60898s actually 61009s. There seems to be random 11 and 12ms times on the X5 column
Circuit 4. lights only 2. R1R2 is 0.51 on 1.5/1.0 now that works out to be approx 17Meters of cable in a little log cabin?
circuit11 lights only 1. R1R2 is 0.46 which works out to be approx 15Meters away
Cooker on 40A without a socket max diss time is 5s not 0.4. it shows only one outlet.
Now the water heater on 10mm cable (for some reason when the method is C) is showing a R1R2 as 0.03, now adding that to Zs will not be anywhere near 1.22. And why on 32A and the cooker on 40A.
Also its not shown as a split board so are all those 60898s actually 61009s. There seems to be random 11 and 12ms times on the X5 column
Circuit 4. lights only 2. R1R2 is 0.51 on 1.5/1.0 now that works out to be approx 17Meters of cable in a little log cabin?
circuit11 lights only 1. R1R2 is 0.46 which works out to be approx 15Meters away
Cooker on 40A without a socket max diss time is 5s not 0.4. it shows only one outlet.
Nicky Tesla
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http://www.esc.org.uk/fileadmin/user_upload/documents/industry/SwitchedOn-25-Locked_2.pdf
page 18 investigation into plastic fuseboards on fire
page 18 investigation into plastic fuseboards on fire
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VERY interesting link.
The most enlightening thing, is the fact that there is no legal requirement to use flame retardent plastic, and most therefore don't.
Isn't it about time that WAS a mandatory requirement of plastic electrical enclosures?
Did you notice they used earth cables as the L & N on the glow test feed 
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Yes, I'll bet an old wooden backed Wylex rewireable would be harder to ignite than some of these modern plastic things.
would certainly stink less when on fire :^O
Sharpend
"It Just Is"
At least with wood you know what fumes you're getting, with plastic its anybodies guess??
mostly PVc so forms of chlorine ie not that different to mustard gas as used in WW1
Its shocking news to me that consumer units do not have to be made from fire retardant materials. Did i really read that .
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