For technical discussions about electricity, electrical equipment with particular emphasis on safe and compliant installations.
Off topic remarks are liable to be moved elsewhere, or in extreme cases to be deleted.
Interesting. Thing that I often wonder about 'crap' products, is how much cheaper/more profitable it is to make a crap product than a half decent one. I see it a lot with Silverline tools. Nine times out of ten they are junk due to small design faults or poor quality materials. It can't cost significantly more to make it better. It's almost as if the market requires a 'junk' product against which the half decent product can be priced against.
I suspect that in some cases it is not a conscious decision to make an inferior product, but is penny pinching or outright fraud by the factory that makes the goods the goods or some component or sub-assembly thereof.
For example a factory making widgets might buy in the power cords from a supplier who gradually cheapens the design.
Also a regrettable number of consumers actually PREFFER and actively seek out the fake mains plugs and leads.
"lighter in weight" "fits in my pocket" "so much neater" And so on.
"Installers and owners of emergency diesels must assume that they will have to run for a week or more"
Fake circuit breakers are infesting the market. Some of them are fairly convincing visual fakes of well known makes.
They contain no form of trip mechanism and offer no protection whatsoever against short circuits or overloads.
I would hope that by buying from a reputable supplier rather than online I would be protected from purchasing duff kit. OK I may pay a bit more but I get it the day I want it and it hopefully comes from the company whose name is on the item not a back street in China.
Dont count on this, reputable wholsesalers have sold counterfeit goods, presumably unknowingly.
I can only see three defences against fake circuit breakers, none of which are very convenient.
1) Use rewireable fuses rather than circuit breakers. Rewireable fuses are still allowed but are discouraged these days. Fuse wire is cheap. MAY under some circumstances need a larger cable. They are not suitable for high fault currents, but should be OK for MOST homes.
2) Use old but in good condition circuit breakers of reputable make, reclaimed from say an office block or department store. Avoid ones from private houses or small busineses that may have been abused for years.
3) Buy new new ones in sealed cartons. Test one unit from each carton with a high current supply, and then dismantle it to inspect the insides. If one MCB from the box passes such testing and examination, then the rest are PROBABLY OK to use. Throw away the dismantled ones, dont try to put them back together and then use. (throw the bits away in two different places)
"Installers and owners of emergency diesels must assume that they will have to run for a week or more"
2) Use old but in good condition circuit breakers of reputable make, reclaimed from say an office block or department store. Avoid ones from private houses or small busineses that may have been abused for years.
I wonder how mcbs are abused in private houses and small businesses?
Overconfidence, not just expert overconfidence but general overconfidence,
is one of the most common illusions we experience. Stan Robinson
In homes and small businesses MCBs are often abused by being very frequently re-set on either a circuit with an intermittent fault or an overloaded circuit.
MOST large companies such as department stores and offices are a BIT more careful and tend to have an electrician investigate any unduly frequent tripping.
"Installers and owners of emergency diesels must assume that they will have to run for a week or more"
I am wondering if this would cause them to trip more easily ( at lower current) which would be annoying
or less easily (at possibly much higher current) which could lead to conductor overheating?
Overconfidence, not just expert overconfidence but general overconfidence,
is one of the most common illusions we experience. Stan Robinson
