Electricians - an awkward bunch to deal with

[paulca]

Take a razor blade, gently cut your self somewhere on your hand so you "slowly drip" bleed, now take a 9volt or even a 1,5V battery and let the poles go into the cut.

Now, the TREMENDOUS pain you will feel in you "entire arm" is profoundly different from a AC voltage pain , like temporary licking on a 240 outlet.

How afraid should we all be?

[MT]

Take a razor blade, gently cut your self somewhere on your hand so you "slowly drip" bleed, now take a 9volt or even a 1,5V battery and let the poles go into the cut.

Now, the TREMENDOUS pain you will feel in you "entire arm" is profoundly different from a AC voltage pain , like temporary licking on a 240 outlet.

How afraid should we all be?

Ask the electrician who told me this story.

[mendip_discovery]

Why are people so worried about 230V mains?

It's only a thump. Doesn't really hurt that much.

So far the calibrator has caught me with 1kV DC but no real current, I pressed the standby button but pulled the leads before it had ramped down. The PAT tester test box got me once with 230 from the mains, I had chosen to use unshielded test leads as the others kept popping out, I unplugged from the test meter before the test box. The best so far was a flash tester that had the foot switch shorted and unknown to me it was on and set to 13kV, I leant over a steel table to plug it in, damn that gave me a thump. At home I isolate and test before touching stuff but it's easy at work to forget the stuff I am dealing with as we are normally well protected from the dangers.

[coppercone2]

well, its been known for killing people occasionally 

[TimFox]

Even 120 VAC mains in North America have been known to be lethal.

[coppice]

Even 120 VAC mains in North America have been known to be lethal.

Even the +-55VAC system used for construction site equipment in the UK can be lethal. It depends to a great extent on how well connected you are to the power. You are more likely to be OK on a cool day than when you are hot and sweaty.

[TimFox]

When I was much younger,  I was told that the world record for low voltage electrocution was at an electroplating plant, but I don't remember the voltage (maybe 48 V DC?).
In medical equipment, where a patient in a hospital bed is wired to the equipment, the US UL requirements (as well as the European regulations) are quite strict.

[MrMobodies]

I tend to have a lot of respect of old electricians who survived 40 years dealing with mains.
The younger ones are the worst, they got 2 weeks certification class and they think they know everything.

I was told once by an electrical engineer over ten years ago who use to hire electricians from colleges and universities that many of them knew how to do the paper work and answer the questions but had no understanding of what they were doing on the job they were hired for and couldn't put two cables together let alone wire up the controls.

[james_s]

Why are people so worried about 230V mains?

It's only a thump. Doesn't really hurt that much.

People can and do get killed by 120V mains. A lot more people get a shock and survive but that is no excuse for a cavalier attitude. If you have sweaty hands and happen to be grasping a grounded object with one hand and come into contact with a live conductor with the other that is pretty close to worst case.

I heard a quote many years ago "There are old electricians and there are bold electricians, but there are no old, bold electricians"

Electricity can kill you, even relatively modest domestic stuff, it's prudent to respect it and treat it with caution.

[james_s]

I was told once by an electrical engineer over ten years ago who use to hire electricians from colleges and universities that many of them knew how to do the paper work and answer the questions but had no understanding of what they were doing on the job they were hired for and couldn't put two cables together let alone wire up the controls.

I don't think I've ever met an electrician that had a university degree. Here there are two paths they typically take, trade school, or more commonly a union apprenticeship. The training is very hands on.

[MrMobodies]

Well this electrical engineer started at a college and was actually working at a security firm too and they did mostly practical there in the 80's. They installed or built long distance power supplies to controls and electric door locks at the time. Unfortunately in the 1990's I heard they got rid of the electrical engineering stuff that stuff and some people who did theirs that I spoke in the 2000's said to me it mostly academic for them and they did very little practical until they started working.

I was at this building firm about 6 years ago, I went with this electrician to network cable the bosses house whilst he ran some 28? amp cooker cable in a ring main (56 amp both ways) for an electric oven in a new kitchen that they extended. He had this assistant who just passed his course from the local college which they got from the Job Center but the electrician didn't like him or want him there. Apparently he was on his phone most of the time tapping away, didn't help the electrician and refused to clean up. Well I cleaned up after myself with the electrician at the end of the day.

So after I finished my stuff I helped the electrician run some of that mains cable through the ceiling of the extension so it didn't get tangled whilst he was upstairs pulling it. Whilst that was happening the lad was in the extension sitting on a work stool staring at his phone looking comically like a little mouse.

I heard them at the office talking about keeping this assistant enrolled there just for his qualifications without him actually coming in (I don't know for what purpose it was suppose to serve them but I didn't ask) as the electricians didn't want him there anymore and called him a waste of a space and they let him go after a year.

[RJSV]

   Working in an assistant position, I noticed right away the licenced guys were keenly aware, of safety and legal responsibilities, (as it should be).  I needed only minor instruction, for some repetitive outlet assembly tasks.  They were very close, to regular interior carpenters, building some structural stuff (underneath) boxes, etc.
   Those folks always, always took the time, to do things right,...as a matter of professional pride.  To this day, I sometimes venture (Google Earth) back to view that 5 story building, downtown San Francisco...it's a lawyer's office now.

[AVGresponding]

I know this video is linked elsewhere on the forum, but it seems appropriate to link it here too, given the talk around lethality of various voltages and currents: