"funnies" out of Ignorance ( or a little knowledge

I have been reminded by another thread of a "funny" I discovered some years ago.

A socket had Live and Neutral reversed. Colours red and black were correct in the socket and at the fuse box. Along the cable route was a junction box installed by the house owner after he had damaged the cable. He had followed the rule "positive connects to negative" ( which is valid when assembling a battery from a number of cells ).

I had one where the guy could not work out why his table lamp was not as bright as it should be.

It has been wired in thermocouple compensating cable.

Unfortunately all these produce danger. Had one foreman who wanted to load up a generator. He used a 45 gallon oil drum and three earth rods nicely fitted into a perspex former he had made filled the drum with water and used as a load. It was not enough load so he added salt.

Forgetting about the electrical danger he had not considered what happens when you pass current through brine. The Na goes to one pole and reacts with water and Cl goes to other and is released as a gas. I could smell the Chlorine a mile off. How they didn't gas themselves I don't know.

Yes a little knowledge is dangerous.

DC generator?

..

Out doors with care of course works well. However we had loads of H2SO4 for batteries which would have lowered resistance of water in same way as salt without the Chlorine.

68kva from what I remember that's a far output into a 45 gallon drum.

The problem is of course as soon as one departs from the straight and narrow there are no instructions. No one will for example lay out how to drive water from a mineral insulated heating element as the whole idea of removing protective items goes against the rule book.

(I have been careful here not to say how it's done. Please don't put how it's done on this open forum.)

We all do things which strictly don't comply with regulations. However with some understanding we can still do it safely. However those copying without understanding unfortunately often get it wrong.

In one job a clever operator had worked out by opening a safety cage one inch he could safely work on the unit. Someone copied without opening the safety cage and lost their fingers. Clearly the procedure would not have been officially recognised and this is the problem.

I found a Honda generator with a 220 output of 55 - 0 - 165 clearly this should not happen so there are no details of how to deal with this.

The so called "Widow Maker" method of connecting a stand-by generator is common in Turkey and as a result most shop keepers know how to do it safely. But in the UK this is just not done hay what so there is no instructions of how to do in a safe manor.

Again please don't say on an open forum what I am talking about. If you know great if not tough.

I am sure we have all when teaching the apprentice said. This is how you should do it. But with care if you do this you save a lot of time. So do we really measure R1 + R2 or do we take a chance and just bang on the loop impedance tester once finished?

Lets face it that's more than most DIY people will do?

As to calculating what size cable we need to cater for volt drop and loop impedance we we have installed enough cables to have a good idea of what will and what will not pass on final inspection and testing so we work by gut feeling forget all the maths.

But tell a foreman that need at least 10mm not 6mm and you find you need to return to class room and show why or just smile when it does not comply.