Earth Leakage Unit Question

[Slow Blow]

Is it law that an E/L/Unit must be installed on a domestic (house) installation or can all circuits be individually protected.

[Dave A]

You certainly don't have to have ELU protection for the entire installation, just the portions that are required to have ELU protection per SANS 10124-1

If the entire installation is on a single ELU, and you intend to only have a portion of the installation on ELU, just watch out the ELU is not also serving as the main switch.

[AndyD]

You can individually protect circuits that require it using 30mA RCBO's. (if you can find a supplier). This won't really be an option if the main switch is an earth leakage unit because you won't be able to achieve discrimination.

[Slow Blow]

Thanks guys but I have been through the book every which way and can't find any part that says an E/L/U must be installed on a domestic installation, am I missing a page or two

[Dave A]

Thanks guys but I have been through the book every which way and can't find any part that says an E/L/U must be installed on a domestic installation, am I missing a page or two

Section 6.7.5 deals with Earth leakage protection.

The section has been amended a number of times, including amendment 8 - so make sure your copy is totally up to date (Edition 1.8).
I see amendments from the original code arising in amendments 1, 3, 5, 6 & 8.

There are also other instances where ELU's are required or material to compliance, for example s6.16.1.4 and s6.16.3.2.3
Not to mention s6.15 - but that should be pretty obvious

[ELECT 1]

You dont have to have an earth leakage. But then you can't have plugs, pool pump, sauna, Jacuzzi etc.
These points require earth leakage protection on them.

[Houses4Rent]

All I know is that Earth Leakage is only on sockets, not on light circuits. But I have no idea why and would like to know.
Why would one not want a Earth Leakage?

[mikilianis]

Hi Houses4Rent a lot of people, I would go so far as to say that the majority of people [I]electricians [I]included do not understand the purpose of a earth leakage unit and consider it unecessary and causes nuisance tripping. Unknown to them the tripping function is there as a protective device and by functioning properly is indicating that there is a fault on the circuits or part of the circuits that are being supplied by the E.L.U. So basically an E.L.U. is a essential safety device designed to protect life and property. Lighting circuits in some installations are not covered by E.L.U. as a safety precaution (make sense, you must have illumination)

[Houses4Rent]

Thanks mikilianis. I understood it to be a safety device. As an enginer i believe that everything must have a purpose and I need to understadn its purpose first before I believe anybody claiming that it has not purpose and can simply be ommited. But I am not so sure about the lighting. I rather have no light than not triggering the E/L when accidentally touching a live light circuit wire. Anyway, so far that did not happen to often. I am not a great competancy of electricity and stay away from things which are beyond basic connections.

Something else: I was quoted 5 hours labour (excl materials) to replace a main breaker and put a surge arrestor next to it. Am I right in saying that its a matter of making a few cable connections at the board which - lets be generous - should not take more than an hour maybe?

[Slow Blow]

Well this wonderful rain has got them E/L/U's tripping like there's no tomorrow, damp faults all over the place and money on the floor

[ELECT 1]

Thanks mikilianis. I understood it to be a safety device. As an enginer i believe that everything must have a purpose and I need to understadn its purpose first before I believe anybody claiming that it has not purpose and can simply be ommited. But I am not so sure about the lighting. I rather have no light than not triggering the E/L when accidentally touching a live light circuit wire. Anyway, so far that did not happen to often. I am not a great competancy of electricity and stay away from things which are beyond basic connections.
Something else: I was quoted 5 hours labour (excl materials) to replace a main breaker and put a surge arrestor next to it. Am I right in saying that its a matter of making a few cable connections at the board which - lets be generous - should not take more than an hour maybe?

Why not get another estimate. Some times there is a bit of extra work involved to accommodate an earth leakage and a neutral bar.
Also some guys can rip you off as well.

[Houses4Rent]

I will get a second quote or simply watch them the 5 hours to see whether they ripped me off. Its worth the fun. I am giving them quite some work from my managed portfolio and I challanged them on a number of times and they could not justify their actions very well or eventually admitted their fault. On soem occassions of course I agreed to their reasoning. This might be a good test to decide to carry on with them or kick them out, but I thought I would be able to get a rough feasibity of 5h labour on this sparky infested thread :-) I actually asked them what is planed to fill 5 hours and I had no response... Maybe that alone says it all.

I also asked around to veryfy their material costs. I simple got a quote from an electrciacal wholesaler without having an account whith them. So anybody can get those prices and it was cheaper by factor 4-5 or so. That is too much of a markup for my liking.

[ELECT 1]

To do the work that was required by you in your first post should be costed out at no more than Two hours, this includes travelling time and buying material time. Thats of course if it was just supply and install and no other work involved.

[Slow Blow]

Thanks mikilianis. I understood it to be a safety device. As an enginer i believe that everything must have a purpose and I need to understadn its purpose first before I believe anybody claiming that it has not purpose and can simply be ommited. But I am not so sure about the lighting. I rather have no light than not triggering the E/L when accidentally touching a live light circuit wire. Anyway, so far that did not happen to often. I am not a great competancy of electricity and stay away from things which are beyond basic connections.

Something else: I was quoted 5 hours labour (excl materials) to replace a main breaker and put a surge arrestor next to it. Am I right in saying that its a matter of making a few cable connections at the board which - lets be generous - should not take more than an hour maybe?

2 hours max for this job.
Got a call out to a restaurant yesterday, 3 phase E/L/Unit not working (will not trip) I was quoted R1,700.00 by the wholesaler for a new one, the client decided he could live without one, you can't force people to install them, that is until one of the staff gets zapped, then there is k@k of note.

[Justloadit]

And did they not charge for eTolls

I know you in CT

That's what they are now doing in Jhb as part of their call out fee