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

[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.

 

[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.

I’m guessing your talking about rcd testing half times 1x and 5x tests and not a zs of the rcd as they are not the same.

 

[streamer]

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.

These values are for if you need the RCD to provide fault protection as well as additional protection. So in most situations they are not applicable.

 

[Octopus]

UPDATE:

The customer contacted said spark about the concerns I had raised and he's coming back on Monday. The customer has asked if I wouldn't mind reviewing the next cert!

 

[freddo]

Interesting certificate, if I handed that in to the QS I think I'd be fired on the spot!

 

[Octopus]

UPDATE:

Here is the revised schedule:



But the installer has also issued a "danger notice"

Issueing "danger notices" - https://www.electriciansforums.co.uk/threads/issueing-danger-notices.124295/

 

[Wilko]

Circuit 9 is perhaps a mistake ... 33 points (sockets) and built as an rfc in 6mm. Hmmm

 

[sparkdog]

Looks like a bit of a NANA.