EICR Failure - lack of continuity

[DPG]

Related to the above, is it the case that if I was using my Fluke 2 Pole tester on a socket across L and E and if unknown to me, the earth continuity was broken further up the ring chain, my 2 pole tester will not detect power at the socket I am testing?

If you haven't disconnected anything prior to testing, then there will be earth continuity from the other leg and therefore you will get voltage between L and E at the socket. So you may well miss the broken earth fault.

 

[Neptune]

Aha and if I were really unlucky and have an earth break in both directions? Just trying to establish a principle.

 

[DPG]

Aha and if I were really unlucky and have an earth break in both directions? Just trying to establish a principle.

Proper dead testing will pick up open connections.

 

[Neptune]

Proper dead testing will pick up open connections.

Does that require more than the Fluke T130 2 pole tester that I currently own?

 

[Dartlec]

Aha and if I were really unlucky and have an earth break in both directions? Just trying to establish a principle.

If both earths were incomplete then you would get full voltage between L and N, but either no voltage, or inconsistent voltages L to E.

That only shows that an earth is present (or not) though, not necessarily a continuity of earth conductors back to the main earth terminal.

That's why dead testing is carried out to check the continuity of the 'ring'.

The continuity setting and reading on the Fluke T130 can give you a basic idea and can be used to confirm that there is no continuity (or that there is some sort of continuity). but for a proper test with the accuracy required for certificates, etc - then a low resistance ohmmeter is required. (Or a Multi Function Tester that includes that, which is the usual equipment electricians have)

 

[Neptune]

Thanks for the explanations @Dartlec.
I appreciate that to do proper continuity testing, I would need additional equipment. That's quite understandable.

I just wanted to understand the reliability of my 2 pole tester when I am about to work on a circuit. I replaced my fluke voltage stick on the understanding that the two pole tester is the most reliable. Presumably this is only the case, if we have continuity on Earth/Neutral (on at least one leg of the ring). If there is no continuity on E/N, the tester would report no power but I could potentially get a belt from the live when I touch it as it is hot.

Have I understood this correctly and/or if this a very far fetched situation? Perhaps in reality testing across L N and L E is adequate.

I would appreciate your thoughts on this.

 

[DPG]

Thanks for the explanations @Dartlec.
I appreciate that to do proper continuity testing, I would need additional equipment. That's quite understandable.

I just wanted to understand the reliability of my 2 pole tester when I am about to work on a circuit. I replaced my fluke voltage stick on the understanding that the two pole tester is the most reliable. Presumably this is only the case, if we have continuity on Earth/Neutral (on at least one leg of the ring). If there is no continuity on E/N, the tester would report no power but I could potentially get a belt from the live when I touch it as it is hot.

Have I understood this correctly and/or if this a very far fetched situation? Perhaps in reality testing across L N and L E is adequate.

I would appreciate your thoughts on this.

It is essential to do appropriate testing. Splitting the ring and doing end to end tests with a proper low resistance test meter is a vital one.

A 'proper' tester will test resistance with a 200mA test current and give accurate results.

 

[buzzlightyear]

Does that require more than the Fluke T130 2 pole tester that I currently own

yes I'm a fried, lol, I'm afraid .

 

[Dartlec]

Thanks for the explanations @Dartlec.
I appreciate that to do proper continuity testing, I would need additional equipment. That's quite understandable.

I just wanted to understand the reliability of my 2 pole tester when I am about to work on a circuit. I replaced my fluke voltage stick on the understanding that the two pole tester is the most reliable. Presumably this is only the case, if we have continuity on Earth/Neutral (on at least one leg of the ring). If there is no continuity on E/N, the tester would report no power but I could potentially get a belt from the live when I touch it as it is hot.

Have I understood this correctly and/or if this a very far fetched situation? Perhaps in reality testing across L N and L E is adequate.

I would appreciate your thoughts on this.

In general a 2 pole tester such as your T130 is considered the best way to check for voltage as it is more reliable.

You are right that if in theory there was no continuity on E AND N, that you might get no result. That is a fairly unlikely event though.

Although if I recall correctly, the T130 does also indicate when held to a "Live" wire with just the main probe - so it combines one of the benefits of the voltage stick.

It is one of the reason that any 'work' should always be done on a dead circuit though. Live testing is only for probing at the terminals of a socket - and really the main purpose of a voltage indicator like the Fluke is to prove dead to work safely...

 

[DPG]

In general a 2 pole tester such as your T130 is considered the best way to check for voltage as it is more reliable.

You are right that if in theory there was no continuity on E AND N, that you might get no result. That is a fairly unlikely event though.

Although if I recall correctly, the T130 does also indicate when held to a "Live" wire with just the main probe - so it combines one of the benefits of the voltage stick.

It is one of the reason that any 'work' should always be done on a dead circuit though. Live testing is only for probing at the terminals of a socket - and really the main purpose of a voltage indicator like the Fluke is to prove dead to work safely...

My Kewtech does the same, ie single probe testing. Obviously for testing for dead you should use the 'proper' two probe test though. I'm not sure having the single probe test is such a good idea

 

[Neptune]

OK. I had overlooked the single probe safeguard.
In conclusion, if I found myself in the rare situation where Neutral and Earth had a broken continuity, just touching one of my probes on Live and the other on N/E will provide an indication of power. Enough for me to be suspicious. I was concerned that there would be absolutely no indication of power in this situation and I could potentially be working on a hot circuit.

Yes, once I have done the test I would isolate the power before - test again - then start work. There may also be situations where I am using these tests to identify the Live wire (thinking of a SL in a lighting circuit scenario)

I think you've cleared that up and put my mind at rest Thanks

 

[static zap]

For your safety .. A known good earth -- Plumbing done in bonded copper ...Could give you a reference for your safety.

..but Skilled electricians will be more on the ball for the un-expected
safety risks .. Locate -identify & analyses whole situation .(from experience)

... (an know he's not leaving a trail of secondary faults from disturbing wiring thats already damaged / beyond saving ...)

 

[nicebutdim]

Yes, once I have done the test I would isolate the power before - test again - then start work. There may also be situations where I am using these tests to identify the Live wire (thinking of a SL in a lighting circuit scenario)

When using the 2 pole tester to check for voltage, always test it first on a known live source and again after testing.

While chances of failure are slim, you only need to be unlucky once.