schedule of test results

[Goldberg]

Exactly.

 

[ricicle]

Exactly.

Why the roll of eyes ?

 

[Goldberg]

Why the post about the steps, if you knew that no judgement is needed to determine that teetering on them is automatically illegal?

 

[ricicle]

Why the post about the steps, if you knew that no judgement is needed to determine that teetering on them is automatically illegal?

Because if say R1+R2 had been carried out at an earlier time using the correct access equipment and that equipment was no longer available then the tester has the option to calculate Zs as he knows he cannot use steps as it would be contravening the Working At Height Regulations.
He would not need to bring back correct access equipment.

 

[Goldberg]

I'm having to pinch myself to believe that we're now talking about steps, which is a logistical matter having nothing whatsoever to do with live testing and live working. You might as well have pointed out that live EFLI testing is impossible with a broken meter.

The main point of my initial post was that live testing is neither illegal, or improper, or wrong, or better, or worse, than calculating EFLI from R1+R2+Ze. The secondary point was that it's wrong to say that you don't do EFLI testing on an individual circuit. sparkyspike might argue that it's just semantics, but it isn't. Nor is it anything to do with steps.

 

[mikhailfaradayski]

Hi Chicd4,

Before this thread decends into pointless gibberish:-

For the purpose of testing, why not bypass/link out the rcd, do the test and then remove the links.

There is absolutely nothing wrong with direct measurement of Zs, so long as done in a safe manner.

 

[Goldberg]

Before this thread decends into pointless gibberish:-

Aren't you a bit late for that?

For the purpose of testing, why not bypass/link out the rcd, do the test and then remove the links.

As a piece of generic advice that's a bit poor, because many installations will have no means of isolating the tail to a main RCD, so unless the circuit in question is RCBO-fed then bypassing the RCD would necessitate live working.

In that situation its's better to use a non-RCD-tripping EFLI tester, or else calculate EFLI having measured R1 and R2.

 

[mikhailfaradayski]

Before this thread decends into pointless gibberish:-

Aren't you a bit late for that?

Yeah, probably. I was thinking of putting that into any responses on this forum if i get to them first, given time, theres strong chance my prophecy will fulfill itself

For the purpose of testing, why not bypass/link out the rcd, do the test and then remove the links.

As a piece of generic advice that's a bit poor, because many installations will have no means of isolating the tail to a main RCD, so unless the circuit in question is RCBO-fed then bypassing the RCD would necessitate live working.

Its not poor advice, its quite valid, but like you say, its generic advice, may not suit all. If he is competent to carry out the tests he is talking about, then he should be able to deduce for himself whether this is possible or not.

In that situation its's better to use a non-RCD-tripping EFLI tester, or else calculate EFLI having measured R1 and R2.

But that would involve buying new kit, whereas bypassing the rcd would mean no new kit necessary.

 

[flameport]

Bypassing or linking across an RCD is completely unacceptable.

There's the possibility of the incomer being live as already mentioned.
The test is intended to confirm the connections are correct and properly made. Undoing them to remove the links would make the test invalid, since you have changed part of the circuit.
There is also the possibility of the links being left in place, making the RCD useless.

The choices are either use a non-trip tester, or calculate Zs.

 

[mikhailfaradayski]

Bypassing or linking across an RCD is completely unacceptable.

Could you point me to regulation to support that?

There's the possibility of the incomer being live as already mentioned.

The Electrician on the ground needs to make that call, nobody else.

The test is intended to confirm the connections are correct and properly made.

No, the test is to ensure that the EFLI is suffiiently low to provide prescibed disconnection times.
Indirectly, the connections in the entire circuit are verified. The competent person carring out the test would check that the circuit is returned to its original state, having correctly inspected the work he carried out.

Undoing them to remove the links would make the test invalid, since you have changed part of the circuit.

I disagree, disconnecting two wires, making a test, then reconnecting (correctly)the same two wires does not change the characteristics of the circuit at all

There is also the possibility of the links being left in place, making the RCD useless.

That would be an act of an incompetent person, that person should not be working with electrics.

The choices are either use a non-trip tester, or calculate Zs.

or remove devices sensitive to testing

 

[Spark123]

Wouldnt it be ZE + ((R1 + R2) x 1.2) to take into account the increase in temperature when the cables are running at operating temp?

We tend to do it the other way around i.e. correct the tabulated value to a level which is comparable to the measured one.