electrical fires

[murdock]

just a rmeinder that illegal connections and bad workmaship are the key causes of fires in electrical installtions...had to disconnect some wiring from an elctrical fire and the reality doesnt hit home until you are walking through a guttered house with personal belongs...family photos...kids toys and stuff like that make it a sad reality...i picked up some family photo which were burnt and could never be replaced...but that wasnt the worse...picking up the childs toys is the reality check...a horrible empty feeling in your stomach...

the the women who was sleeping when the fire broke out was woken by a massive explosion...which was the aircon unit exploding and was blown right across the lounge and landed in the kitchen and took the kitchen cupboards off the wall.

[murdock]

the cause of the fire...a connector block on the supply to the aircon unit...as you can see by the picture...the cable did not reach the plug socket so the aircon tech just fitted a connector block to the wire and joined a piece of cabtyre with a plug top bingo quick fix which completely gutted a granny flat...lucky for the old lady the explosion woke her up and she managed to get out before being burnt to death.

next time you look at a recent aircon installtion check how many times these aircon tech do this type of thing...the way i see it the aircon guy who made the joint should be held liable for all the damages estimated at around R500 000 including the old ladys hospital bill...why because instead of doing the job right the first time by replacing the cable with a longer piece he took a short cut.

[murdock]

this one we managed to catch before it got out of control...a plug behind a washing machine...the customer could smell something burning but didnt know where it was coming from...loose connection in the plug top.

[AndyD]

where it was coming from...loose connection in the plug top.

I've seen more fire scenes caused by overtightened connections on plug tops which causes the termination screw in the plug to cut through a large percentage of the wire strands. It then overheats under load and welds the plug pin into the wall socket.

[murdock]

yip i agree an overtight connection is just as bad as a loose connection...

that is why i looked into a torque screwdriver a couple of weeks ago...they are over R3500 ex vat...i caqnt see tooo many electricians buying torque screwdrivers...i ended up getting a torque wrench for busbars and big circuit breakers...because i dont see how it helps that i find hotspots with the thermal imager then just create another bad connections again once i have repaired it...so now i can torque the bolts to the corrent tension...

i solder the wires or put a botlace ferrol on the wire like cabtyre.

the new cbi circuit breakers have a plate that pulls tight onto the wire now like the m&g ones...only problem is i have found they dont hold the wire tight...you have to move the wires around while tightening then just before you close the panel you have to recheck all of them other wise.

i like the hellcon connectors they are spring loaded...while doing an inspection on one of my staffs connections i found that he wasnt pushing the wire right to the top which could cause a problem...and once we take them off we dont reuse them even though you can.