Questions

[Spark123]

I'd go for the lower disconnection time where the supply is TT which is normal to have RCD protection for anway.

 

[Jacobssi]

Thanks spark but apparently it is 5s.
Two hours after posting that I took my C&G 2382 and that came up! Of all the questions... Going through the regs this last week,there are so many contradictions! by the way, anyone know what 125 v D.C is classed as? Extra low/low/ reduced low/ SELV I went for low

 

[imroberts]

Have you looked to see if this discrepancy is resolved in the forthcoming Amendment?

If it isn't then you could feed this back via a DPC comment.

Doesn't seem to be in the Amendment.

How do we feed back?

 

[ban-all-sheds]

I haven't bothered to download it yet - I'm assuming there are instructions on how to submit comments.

 

[GaryMo]

anyone know what 125 v D.C is classed as? Extra low/low/ reduced low/ SELV I went for low

Low voltage.

 

[Jacobssi]

Thanks Gary.

 

[Jacobssi]

'rule of thumb' calculation. Is the value 1.6?and where would we use it?

 

[Spark123]

Rule of thumb in respect to what?
We used to use a three quarter rule of thumb to calculate the maximum permissable measured EFLI from the maximum tabulated value.

 

[GaryMo]

Which is now 80% (BS7671 Appendix 14)

 

[Jacobssi]

Sorry to be vague, I remember using it at collage when the tutor wass showing a calculation but I cant' remember what it was for.

Yes Spark I think it was with regards to Max. ELI.

 

[Spark123]

The max measured figures are fairly well published now so there isn't really much need to use the tabulated ones, however they do tend to give you the tabulated ones in the practical for the C&G2391 and expect you to know that you need to correct it for temperature, as Garymo says it is now 80% which equates roughly to a 70deg C conductor being measured at 10deg C.