Are you based in Frimley????????

[Octopus]

So I got a call from a customer asking me about something I did in Feb 16 - so I duely paid a visit. Knowing they had had some work done I asked if I could see the certificate..... as I didn't take mine with me!

Now bearing in mind a new fuseboard had been fitted, the kitchen had been hacked around, downlights had been fitted and a wall removed I was expecting an detailed EIC........

Er no, the EIC simply said replacement fuseboard..... which had all 10 "slots" used.

This is a photo of the test results sheet.........

Sorry its side ways

Anybody want to play "spot the mistake / ommision / unusual entry" with me?

 

[ipf]

How many DBs are there if this is #1?
How is measured Zs N/A for RCDs?

How is it applicable?

 

[Sparkingmad]

How can they tick polarity on the circuits they haven’t tested or entered results for R1+R2 or Max ZS reading? Ring Circuit 9 20000 so near enough useless continuity on R1, the list of errors and inconsistency just keeps getting worse. So what was the IPf at that board left blank too.

 

[Deleted member 26818]

How is it applicable?

To start with, the form asks for the maximum allowed by BS7671.
I guess technically none of it is applicable as the certificate is for a board change.
I wonder why it’s applicable for one RCD, but not for the other two?
It’s also odd that they conducted no IR tests.

 

[Sparkingmad]

I was wondering about forwarding a copy to Elecsa .. I do have his details and number!

Maybe get the customer to get in touch with elecsa and send a copy of that cert complete with installer name and number and ask them to confirm if that certificate is genuine.

 

[Ian1981]

To start with, the form asks for the maximum allowed by BS7671.
I guess technically none of it is applicable as the certificate is for a board change.
I wonder why it’s applicable for one RCD, but not for the other two?
It’s also odd that they conducted no IR tests.

I think he means you don’t measure a zs for the rcd hence the box is marked N/A on the certificate for both.
Also why would you write 1667 ohms for a 30mA rcd for maximum zs when that referes to the touch voltages not rising above 50 volts it’s not really applicable to the certificate in my opinion, at least that is I’ve never wrote it in unless the rcd is proving fault protection as the sole means such as a TT system.

 

[Deleted member 26818]

Is someone suggesting here, that when you install RCDs, you don’t measure the Zs?

 

[Ian1981]

Zs of the circuits are measured
Rcd tests are carried out
Ze etc etc.
If the rcd is external to the main consumer unit then the distribution circuit supplying and connecting to the rcd is measured but no not the physical rcd no.
That’s what rcd tests are for is it not?

 

[streamer]

I wonder why it’s applicable for one RCD, but not for the other two?

The first one is an RCBO (61009), the other two are two RCDs (61008) covering a group of MCBs each. So the RCDs themselves don't require a Zs test, rather the MCBs they cover do. I think the way he has used a circuit to write down the RCDs is confusing.

 

[ipf]

The first one is an RCBO (61009), the other two are two RCDs (61008) covering a group of MCBs each. So the RCDs themselves don't require a Zs test, rather the MCBs they cover do. I think the way he has used a circuit to write down the RCDs is confusing.

Yep. I think someone's getting mixed up.
He's given the RCD's a circuit number. I usually replace the cct no with RCD 1 and RCD2 and leave a blank line, except for the RCD times and rating.

 

[ipf]

Is someone suggesting here, that when you install RCDs, you don’t measure the Zs?

Sure am.....not for the RCD's themselves, anyway.

 

[Deleted member 26818]

You have to know the Zs to ensure the RCDs will work.
<1667 Ohms for 30mA
<500 Ohms for 100mA
<167 Ohms for 300mA
<100 Ohms for 500mA.
You cannot say it’s not applicable.
You can leave it blank because you’ve tested all the circuits protected by the RCD, or you can record the highest measured value for the circuits the RCD protects.

 

[streamer]

Post deleted

 

[ipf]

In this case, it's not applicable. There's at least one Zs reading for each RCD protected group.

 

[streamer]

or you can record the highest measured value for the circuits the RCD protects.

Have you ever done this? If you have then I suspect you are the only one!

 

[Ian1981]

You have to know the Zs to ensure the RCDs will work.
<1667 Ohms for 30mA
<500 Ohms for 100mA
<167 Ohms for 300mA
<100 Ohms for 500mA.
You cannot say it’s not applicable.
You can leave it blank because you’ve tested all the circuits protected by the RCD, or you can record the highest measured value for the circuits the RCD protects.

By taking a zs of the protected rcd circuits and even the ze then we know that 50v/0.03 is satisfied anyway however the zs is measured to ensure ADS of the over current protective device.
Nowhere does any literature on testing say that the rcd requires a separate zs test and why would it?
Any specific rcd testing can be found in GN3
It is the rcd tests that ensures the rcd will disconnect in the required times.