ELECSA Certification Scheme Elecsa Part P Scheme - Testing Queries

[GLENNSPARK]

if you mean the main earthing then use the adiabatic to prove its good for time/current...

 

[ray-bentos]

if you mean the main earthing then use the adiabatic to prove its good for time/current...

No the 6mm cable feeding 9.5kw shower, albeit REF method C

 

[Richard Burns]

Ib<In<Iz

Ib is 41.3A
In is 45A
Iz is 47A

Sorted.

 

[ray-bentos]

This brings another problem to the fray which is my chosen CU only has 40 or 50amp MCBs. I know there is no requirement to provide overload protection for fixed loads but then my breaker is lower than my design current at 40amp and 50amp is above the 47amp allowed by the cable?

Alternative is to use an MK Sentry CU which has the 45amp breaker option

 

[SJD]

The 9.5kW shower is perhaps only 9.5kW at 240V, taking just under 40A. At 230V it will be a lower output? If you use a 40A MCB, I'd be surprised if it tripped.

 

[ray-bentos]

It has run fine for nearly 2 years on a 32amp MCB, its the design issues I'm worried about due to the Elecsa assessment.

 

[Richard Burns]

Either take SJD's suggestion 9.5kW @ 240V is 38A at 230V so a 40A breaker is fine.
or use an MK / Schneider CU to use a 45A MCB
Or as a shower is designed as short term load with no variation and a 40A MCB will take 41.3A for in excess of 2 hours this will not trip and cause nuisance.
The cable is protected as it can take 47A, you have short circuit protection and you are not designing a circuit where a small overload of long duration will occur. You are designing a small overload of short duration; this is permissible in the regulations, as other wise diversity calculations would not be possible. Although no diversity is permitted for showers this is a design decision that is safe and in accordance with common practice .

OK so write that down and have it available just in case the assessor should ask about your design calculations, (they very likely won't, unless they are reading this post!)

 

[KFH]

The assessors I have met are looking to pass you. You just have to make it easy for them. Make sure you have all the items on the assessment check list sorted and available. If you do not know the answer to a question do not try to bluff, just say you don't know and say where you will look it up, usually the On Site Guide. None of us, well perhaps the odd one, can remember everything.


Good luck.

 

[Prince1983]

Hi. I hope you've got some good news to share

 

[ray-bentos]

Yes got assessed yesterday, passed no worries!

 

[Dipzy]

Well done mate, was it as tough as you thought it might be?

 

[ray-bentos]

No it wasn't at all, in a strange way I actually enjoyed it once we got going, was a chance to exercise the old grey matter and even bounce a few questions off the assessor to get their take on things.

The assesor actually said himself he would have put the wire in question in trunking for the 6 inch run above the CU - it looks a c*ck clipped to wall (it is in pantry but just not a massive fan of bare T&E). He was pleased that I had considered the consequences of this with regard to CCC all the same so I guess they aren't trying to trip you up and if you can back up what you are doing then you have nothing to worry about.

I guess just nerves took over, all the mentions of "assessment" and the huge sums of money involved.