Economy 7 Testing

[Former Sponsor TM]

OK, I've done a search for the above on the forum and I don't really think a definitive answer has been given, so I pose the question for discussion; how would you carry out live tests on an economy 7 circuit where you cannot gain night access?

I pose the following:

1) For non RCD protected E7 circuits - Providing a Ze measurement can be obtained, Zs can be ascertained by calculation;
2) RCD Protected E7 circuits - a temporary supply is provided to the E7 circuit from a permanent source in order to test. This could also be used for non-RCD protected circuits and then recorded on your EIC, EICR or MWC.

 

[davesparks]

A Zs test can be done without making the supply to the E7 board live, assuming it is located near to the 24hr board.

Link L to CPC at the far end of the circuit.
At the board, isolate the E7 board via the main switch if you haven't already.
Put the E probe from your meter on the outgoing live terminal of the circuit in the E7 board.
Put the L probe on a live in the 24hr board.
Test it.

 

[Engineer54]

That was my thoughts when i looked at this post earlier. You have described the procedure far more easily than i would have, mine would probably take up 3 to 5 times more space. lol!! It's why i left it to see if anyone else had a stab at it, and thankfully you came along!! lol!!

To be honest i was in the middle of something i was doing for work tomorrow at the time and have just come back to have a look, to find it's sorted!!

 

[Former Sponsor TM]

Thanks for the response - so what about RCD tests on an RCD protected E7 circuit?

I don't want to start off the 'lim' argument on an EIC again so would we agree on a temporary supply for trip time measurements?

 

[davesparks]

Move the RCD into the 24hr board, test it then put it back again?
You are only testing the device after all.

 

[Octopus]

Go and test after midnight?? lol

 

[davesparks]

That was my thoughts when i looked at this post earlier. You have described the procedure far more easily than i would have, mine would probably take up 3 to 5 times more space. lol!! It's why i left it to see if anyone else had a stab at it, and thankfully you came along!! lol!!

To be honest i was in the middle of something i was doing for work tomorrow at the time and have just come back to have a look, to find it's sorted!!

I use this method often enough doing stage lighting installs.
24 x 10A single point radial circuits fed by each dimmer, you can't do a Zs test the 'normal' way as it would be going through the dimmer circuitry and give some very odd results.
So my assistant goes along the lighting bars/outlet panels with the L-E shorting plug, I stand at the dimmer doing dead and then live tests on each circuit (obviously they pull the plug out for IR then put it back in) We can rattle through 96 circuits before lunch if the access to the sockets is favourable.