EICR or EIC Certification

[Wardy1980]

Hi,

If you were to change a distribution board within an commercial environment, and you couldn't get access to circuits for R1R2/ Max Zs, previous test results saying unknown on circuits.
Surely you cannot issue an EIC Cert as you cannot verify circuits are compliant as it is virtually impossible to trace cables back. (no access)

Would you change D/B & put circuits back where they came from and issue an condition report or EIC. All I have put on test results is Not Verified (N/V) where you cannot physically test outgoing circuits. This okay?

 

[westward10]

Get this a lot on commercial I often allow for the unknown circuits but don't connect them until someone shouts this that and the other isn't working. After a few days you could assume they are redundant but always leave them so they can be installed somewhere along the line someone may shout something is not working. EIC in any case.

 

[Risteard]

If your job is to replace the DB then this is all you are certifying. So certainly you need to ensure that disconnection times will be met by the new devices, and you want to ensure that you have correctly terminated cpcs (arguably this could be verified to the first rather than last point on the circuit). But you are not certifying the existing installation - however you need to ensure that your new DB installation does not impair the safety of the existing installation, and also that the existing installation does not impair the safety of your work. N/V isn't used on an EIC - N/A is the only option if you are not carrying out a test.

 

[Ian1981]

If your job is to replace the DB then this is all you are certifying. So certainly you need to ensure that disconnection times will be met by the new devices, and you want to ensure that you have correctly terminated cpcs (arguably this could be verified to the first rather than last point on the circuit). But you are not certifying the existing installation - however you need to ensure that your new DB installation does not impair the safety of the existing installation, and also that the existing installation does not impair the safety of your work. N/V isn't used on an EIC - N/A is the only option if you are not carrying out a test.

How far would you go to verify R1+R2 in say a large commercial property.
Surely you must verify at the last point of the circuit to make sure your disconnection times are actually verified, as with a lot of commercial installations not everything is required to be rcd protected so the disconnection times for non rcd circuits needs to be assured.
Thinking lights installed in conduit, swa wiring to fixed equipment etc.

 

[westward10]

Too many parallel paths with metal containment, Zs job done.

 

[bigspark17]

Why cant you "physically test" test outgoing circuits? On a consumer unit you must ensure circuits are safe for renergising on your new ocpd's. You must IR (l&n-earth) and take Zs reading at furthers point of every circuit otherwise how can you prove the disconection time is being met.
Why is the board being changed? Has it failed any test or is it someone has visually failed it?
Im affraid the excuse dont have acces is not good enough as the propriator should have been told pre cu change that youll require access to all circuits.

 

[Ian1981]

I always personally try to take the R1+R2 route of testing a bit like initial verification rather than the periodic 'just zs it ' approach
Just my preference.
Though I'd have thought at least R2 needs verifying were exposed conductive parts are present on equipment before shoving a test current of around 25amps in the circuit although most test instruments will abort the test if the voltage to earth rises above 50v

 

[Risteard]

How far would you go to verify R1+R2 in say a large commercial property.
Surely you must verify at the last point of the circuit to make sure your disconnection times are actually verified, as with a lot of commercial installations not everything is required to be rcd protected so the disconnection times for non rcd circuits needs to be assured.
Thinking lights installed in conduit, swa wiring to fixed equipment etc.

Disconnection times would be verified with Zs rather than R1+R2 or R2. After all, it is an already energised installation.

 

[Wardy1980]

How can you measure zs at the furthest point of circuit if you can't get access or know where the circuits are.. im talking a 12 storey office block here.. some circuits are unknown so how can you get an zs value on them?

 

[Octopus]

Have you actually done this work or are you asking the best way to do it?

Either way an EIC is necessary........

Not sure I would agree to change a board where I couldn't identify all the circuits?

How do you know you can actually turn the cu off for any period of time?

 

[bigspark17]

How can you measure zs at the furthest point of circuit if you can't get access or know where the circuits are.. im talking a 12 storey office block here.. some circuits are unknown so how can you get an zs value on them?

By getting access.. you cannot just renergise all circuits without knowing what your energising or if its safe to do so. As @westward10 said leave unkown circuits disconnected and youll soon identify alot of thoose circuits then you can test them before renergising.
Why is the cu being changed?? Are you the person signing the EIC?

 

[Risteard]

How can you measure zs at the furthest point of circuit if you can't get access or know where the circuits are.. im talking a 12 storey office block here.. some circuits are unknown so how can you get an zs value on them?

I wouldn't connect circuits without knowing what they were. How would I know there weren't just live cables at the end of it otherwise with nothing connected?

 

[davesparks]

How can you measure zs at the furthest point of circuit if you can't get access or know where the circuits are.. im talking a 12 storey office block here.. some circuits are unknown so how can you get an zs value on them?

Before starting the job you discuss this with the customer, and get it agreed that untraceable circuits will not be reconnected.
Don't wait until,after you've done the job to think about it because you will end up costing yourself money tracing these circuits so that you can reconnect them.

 

[superspark]

Discussion and agreed and signed limitations, and terms.
If this is a 12 story office block, does it supply ccts on all 12 floors ? or is this a main DB. I think you would be far better advising the client that you need to do an EICR BEFORE the change, to at least trace all of the ccts, then when everyone is happy / sattisfied change the Baord over. Depending on what the building is, I would feel very unconfortable about changing the board then leaving everything disconnected that I could not trace, You could be disconnecting servers in locked rooms, Alarms in locked rooms, I personally think you would be leaving yourself wide open for lots and lots of visits, and possibly damages for call outs and claims, Just my thoughts.