A friend and I were discussing all the "fun" things you run into on a job or service call. I've had electrocuted rats in the meter socket, lots of extension cords buried in plaster, conduit as the nuetral, etc. Does anyone have any good stories? No " I went to change a bulb, and the lady was naked.." please.
But is that last example a 'best' or 'worst' story? ;-)
Depends on the lady. ;-)
How about the house that had been 'rewired' using less than 10mtrs of cable? It kept tripping the RCD (the reason I was called in). a quick look under the floorboards showed that some clown had wired nice new outlets down to the old rubber covered cable and simply used connector blocks to join it all together. Needless to say it failed every test, especially the doorbell push button that had full mains voltage running to it through what looked like an old bit of speaker wire. Customer was not impressed with the report and refused to believe I wasn't just trying to jack the bill up as far as possible. As far as I know it's still like it.
Jb
Ok, An apprentice that was known for smoking pot fell asleep on a ditch witch and let it run out across the tundra for quite a distance before someone woke him up. That was in about 1981 at Prudhoe Bay, Alaska on the Arco side. It was a bull rail job.
Not so much a consumer story, but I once helped refit a control system = in a paper mill, where the E-Stop circuit had been wired with 20 = normally open switches in parallel - all operating a relay with *one* = normally closed contact which protected the machine and the workforce!!
long ago at a boy scout camp i was assigned the task of finding out why the voltage in the directors cabin was low. the wiring was old and strange. several cabins were daisy chained together. off i went with my trusty volt meter. i finally discovered a cartridge type fuse that had about 10 or 20 volts across it. it had oxidized in place. rotating it polished the contacts enough to restore proper operation. i happily returned with my mission accomplished only to find the doors open, smoke wafting out and angry people yelling at me. you see unbeknownst to me they had a pot of Chile simmering on and electric oven.
life is unfair. i got the blame for burning dinner and i wasn't even in the building at the time.
So, how many of those switches actually functioned?
Believe it or not, all of them - I think the word 'lucky' doesn't go far = enough!
Not exactly a job/service call, but a building I used to work in had an HVAC system using possibly the cheapest type of single setpoint thermostats available. Following a management directive to save energy on air conditioning by setting them all to 80F, it was discovered that this resulted in the heat coming on until that temperature was reached. There was no way to set seperate heating and cooling temperatures.
in article snipped-for-privacy@uni-berlin.de, cupra at snipped-for-privacy@f2s.com wrote on 9/1/04 7:03 AM:
Maybe I am not up to the current jargon. To get my chuckle I need to know what an "E-Stop circuit" circuit is and what kind of protection it is to provide.
Bill
snipped-for-privacy@f2s.com
i take to be emergency stop. i believe in most cases its supposed to be normally closed with all the switches in series.
the big disadvantage in the above mentioned scheme is that IF the relay coil fails the stop wont work.
Some electricians were blowing compressed air into a conduit feeding a sump pump in an electrical manhole to try to determine from where it was being fed. This occurred just as I was entering the control cubicle for a piece of production equipment. It turned out that the sump pump was being fed from a spare circuit in a panel board in this control cubicle. I entered just in time to get the bejeezus scared out of me by air, water, and mud shooting out of the conduit. Not good for control equipment.
Yep - normally closed so if wires fall out or are cut accidentally, the = machine will stop....
Yes - and if a switch failed nobody would know (until an emergency = happened, of course!)
Hmmm.. Reminds me of a Three Stooges short with a similar theme of water coming out of the electric appliances due to unfortunate misconections from the stooges as plumbers. I believe it was called "A Plumbing We Will Go". Hilarious!
I remember seeing a neighbors house that was wired 100% completely with white wires. Sure must of been fun for the remodeling contractor electrician.
Beachcomber
You're right, it was "A Plumbing We Will Go". It was a funny episode! The owner of the house was having a party and they were watching TV (Niagra Falls specifically). Now you have to remember that this was ~55 years ago so TV was new. I remember one of the guests saying "Oh, it's so lifelike." Then the water comes through the TV screen. Very funny....
It was my first day with a new company, and I was assigned to make an aluminum bracket. As I was happily chopping away with a band saw I realized that the saw was plugged into a power-strip, and the power-strip had flopped into the walkway. So I reached down and grabbed hold of the thing, only to have it blow up in my hand. It turns out the aluminum dust from the saw had fallen inside...the rest was lightning and chemistry!
Kevin
Be advised that normal for a relay is sitting in the box on the dealers shelf without even wiring it let alone energizing the coil. The correct way to wire the circuit is with the normally open contact providing control power to the motor starter control circuits of the lines machines. The NO contact is held closed by the current flowing to the relay's coil through normally closed switches (form B) wired in series. The operation of any emergency stop button or any failure of any part of the circuit returns the relay to it's relaxed or normal condition thus depriving all of the assembly lines motor starters of control current. The motor starters drop out thus stopping all of the lines machinery. Such circuits should also have one side of the circuit grounded between the power supply and the emergency stop relay. No stop buttons are installed in that side of the circuit. The other side of the circuit would have a fuse connected to the power source then all of the stop buttons followed by the coil of the emergency stop relay. That makes it impossible for multiple ground faults to go unnoticed thus bypassing the contacts of one or more of the stop buttons.
-- Tom H
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