Ring or radial . . . That is the question

[JohnW2]

The Zs requirement for a 3A fused circuit is a lot higher than that for 32A.

Sure, I said/implied that in my words that you have just quoted, but that different requirement is a consequence of the different OPD, regardless of the 'type' of circuit, or what one chooses to call the bit of the circuit in question.

May be I'm generalising too much but the VD for a fan or a light may be less stringent than that for main circuit which may supply all sorts of things.

Well, as far as the regs are concerned, all that matters is that the voltage supplied to equipment does not compromise 'safe functioning'. As for the guidance, the suggested VD limit for a light is, of course, more stringent than that for most other sorts of load.

Kind Regards, John

 

[EFLImpudence]

As for the guidance, the suggested VD limit for a light is, of course, more stringent than that for most other sorts of load.

Not if it doesn't matter.

 

[JohnW2]

As for the guidance, the suggested VD limit for a light is, of course, more stringent than that for most other sorts of load.

Not if it doesn't matter.

Even if there are arguments about the semantics, I would say that the intent of the guidance is clear enough. Whether you (or I) feel the issue 'matters' enough to take any notice of that guidance is, of course, a different thing!

Kind Regards, John

 

[EFLImpudence]

525.201

 

[JohnW2]

525.201

Although I didn't cite the reg number, that's exactly what I said a couple of posts back! IMO, there are probably very very few loads which would become 'unsafe' because of reduced supply voltage of any degree!

Kind Regards, John