Max power draw on wall plug

It's pretty common for DB boards to be wired with certain circuits like the geyser and stove circuit breakers put before the EL detection because of nuisance tripping. Personally I wouldn't be happy having ANYTHING not on EL, especially the stove and geyser. I've never understood the whole nuisance tripping reason, surely the lives of yourself and your family are more important than saving a few rands because you can't be bothered to sort out what's causing the nuisance tripping.
 
deweyzeph said:
It's pretty common for DB boards to be wired with certain circuits like the geyser and stove circuit breakers put before the EL detection because of nuisance tripping. Personally I wouldn't be happy having ANYTHING not on EL, especially the stove and geyser. I've never understood the whole nuisance tripping reason, surely the lives of yourself and your family are more important than saving a few rands because you can't be bothered to sort out what's causing the nuisance tripping.
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Nuisance tripping caused by poor power distribution and lightning is the most common reason.

The other reason was/is that some appliances DO have leakage to earth when operating perfectly normally that might be in excess of the value allowed by the EL unit.

Besides, after 40 years without one single incident, the safety issue is moot.
 
deweyzeph said:
It's pretty common for DB boards to be wired with certain circuits like the geyser and stove circuit breakers put before the EL detection because of nuisance tripping. Personally I wouldn't be happy having ANYTHING not on EL, especially the stove and geyser. I've never understood the whole nuisance tripping reason, surely the lives of yourself and your family are more important than saving a few rands because you can't be bothered to sort out what's causing the nuisance tripping.
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Think about a stove hob
You cooking and suddenly you're pot boils over spilling water on tho hob.

With it on EL it will trip and you will have no way to dry it out.

With it properly earthed it wont trip but the heat will evaporate water fast , if there a bit moisture between earth and live the earth will redirect that current to ground.
 
thehuman said:
Think about a stove hob
You cooking and suddenly you're pot boils over spilling water on tho hob.

With it on EL it will trip and you will have no way to dry it out.

With it properly earthed it wont trip but the heat will evaporate water fast , if there a bit moisture between earth and live the earth will redirect that current to ground.
Click to expand...

Stoves should have an dipole isolator switch installed after the circuit breaker so drying it out wouldn't be a problem. The problem is that if that water contacts the live wire and energizes the metal surface you are going to fry yourself to death if you touch it and there's no EL to automatically break the circuit.
 
As a follow up to my CoC certificate. I found that the wall socket that caused the issue was in fact not faulty, (but changed it anyway). It was full of damn ANTS!

What was really interesting was that a modern analogue phone installed about 1 meter away suddenly started working far better soon after all the ants and their mess was cleaned out.

Brought back home just how easily unwanted EMI interference can be generated and the truly weird sources of such noise!
 
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It is actually disgusting that this sort of nonsense is allowed.
But to get technical, we need to know what the main CB rating is as well as the rating of the CB for wall socket.
 
Reviving this. I am currently involved in establiahing some new businesses. One large format printer says it is rated at 5kw. A coffee machine for restaurant also rated at 5kw. Blenders are rated at 4.4kw. All clearly wrong, as all are driven off a normal 3 prong socket they came with. The DB has all plugs linked to 8A trip switches, and none ever trips. How on earth do people lately rate equipment? How do they get to these ratings? And, yes it says W and not VA.
 
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Pax said:
Reviving this. I am currently involved in establiahing some new businesses. One large format printer says it is rated at 5kw. A coffee machine for restaurant also rated at 5kw. Blenders are rated at 4.4kw. All clearly wrong, as all are driven off a normal 3 prong socket they came with. The DB has all plugs linked to 8A trip switches, and none ever trips. How on earth do people lately rate equipment? How do they get to these ratings? And, yes it says W and not VA.
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Maybe those are peak ratings, not steady state. On startup, the motors will draw a significant amount of current for a short period, before coming down. Look at the circuit breakers time-current curve, it might be possible to go over the cb rating for a short period of time before it trips.
 
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Running the house on a 5kW inverter, I am very careful of what is connected and switched on

A JURA coffee machine has a label stating "1450 watts". But measuring the current with a clamp meter, it is 2.5 amps, or 575 watts

Then a toaster which states "700 watts" was found to use 3.6 amps, or 830 watts.

A Samsung convection microwave uses 3100 watts, so that is out

I bought a 700 watt Russell Hobbs microwave and this works just fine. It takes a little longer, but at least works (during load-shedding)

The inverter supply has its own (separate) earth leakage relay. You cannot attach inverter neutrals to a mains e/l
 
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