Pyro feeding domestic db

[harryharman]

Carried out loft extension in old ladys house, normally install sub-board just for loft supplies but she wants her old db (3036 fuses) changed for a new one and loft circuits installed all in new split rcd board. Ok fine done this few times before but at this house, the head is in the front garden with a pyro coming out feeding her db. Any suggestions as to what I should do in terms of replacing the pyro as I dont think its a good idea to still use?! Any help is much appreciated, thanks in advance.

 

[monkeyelectric]

Can you replace it with swa?

 

[harryharman]

Yeah but the run is about 7 metres so would I have to put a switched fuse in after the meter before the run?

 

[monkeyelectric]

Yep, the job would also need notifying to building control too

 

[harryharman]

My firm is NICEIC approved so would we still need to inform building control? And does the SWA have to be 25mm ?

 

[monkeyelectric]

You'll have to do your cable calcs to work out the size

 

[harryharman]

Thanks buddy

 

[Richard]

Why isn't the pyro any good for continued use??

 

[harryharman]

I don't really know much about pyro, never used it- it doesn't look very big and it must be 50+ years old, I just thought if I'm changing the board I may as well sort out the supply cable as well?

 

[Richard]

That's fair enough. As for the sizing of the cable, that will depend on your loading calculation. What is the earthing arrangement out of interest?

 

[harryharman]

Tn-s system

 

[SPARTYKUS]

Pyro can take more current, it might be up to the job you never know. It's CCC is in the regs! Might not be as old as you think. Good stuff.

 

[UNG]

Any suggestions as to what I should do in terms of replacing the pyro as I dont think its a good idea to still use?! Any help is much appreciated, thanks in advance.

Don't change it if it tests out ok

Why isn't the pyro any good for continued use??

My thought as well would probably outlast anything you would replace it with

I don't really know much about pyro, never used it- it doesn't look very big and it must be 50+ years old, I just thought if I'm changing the board I may as well sort out the supply cable as well?

I think now might be a good time to learn about Pyro and it's operating characteristics before ignorantly dissing it. How have you identified it's age if you don't know that much about Pyro

Pyro can take more current, it might be up to the job you never know. It's CCC is in the regs! Might not be as old as you think. Good stuff.

It's a shame that the qualities of Pyro don't seem to be highlighted during training these days a lot of very serviceable Pyro has probably been ripped out in ignorance in the last few years

 

[SPARTYKUS]

It might very well be ok, as said test. 6mm2 heavy duty rated (clipped direct) at 70A. And it probably looks smaller than you'd expect.

Btw I have v. Little practical experience of pyro too, just testing of, mainly!

 

[harryharman]

Ok that sounds better, I'll do an IR test on it and hopefully it will all be ok, but I think the earth coming in with it is only a 10mm so I'm pretty sure ill have to upgrade that anyway? Also how do you know what size pyro is, is it normally marked on the cable?