PIR codes, help please

[sjm]

Hi guys.
Just wanted to ask what code you would give an old wylex fuse board with wooden enclosure. It does have the plastic (plexolin I think it's called) plate at the back.
Also 2.5 T+E with 1.0mm CPC used for a ring main on a 3036 fuse.

Thanks in advance.
Steve

 

[Deleted member 26818]

115 is for a conductor with an initial temperature of 70ºC or greater.
I'd be more inclined to use 143.

 

[Guest123]

TBH there are so many different factors that could influence the outcome it's difficult to stamp an assured answer one way or t'other.

I calculate to 1.15 (spot on somerset ) ergo a 1.0mm cpc is insufficient to withstand the fault current for the given time.

All IMO.

 

[nickblake]

If its missing its spark cover then its a code 1 code 2 if its in place[/QUOT

and what's the code for 2" nails in the fuse holders. minus???

nothing wrong with a nail in the fuse holder eliminates neusance tripping code 1 i think , i hate rewireable fuses they should be banned so easy for mis use and electric shock every time you take the fuse carrier out you expose live busbars , yes i know the should switch it off when the do it but its the general public we are talking about and 80% just pull out the fuse its a miricle people havent been killed with them or perhaps they have

 

[telectrix]

looks like your'e returning to your normal self, nick.

 

[Deleted member 26818]

TBH there are so many different factors that could influence the outcome it's difficult to stamp an assured answer one way or t'other.

I calculate to 1.15 (spot on somerset ) ergo a 1.0mm cpc is insufficient to withstand the fault current for the given time.

All IMO.

Is 115 for k an appropriate value to use, considering the conductor is unlikely to initially be at 70ºC or greater?

 

[Guest123]

More appropriate than 143 I feel.

 

[i=p/u]

nothong wrong with the 3036 fuse-/boards if has been designed to the standard

 

[PC Electrics]

2.5/1.0 ring final on a BS 3036 fuse is a code 2 as it fails the adiabatic equation for this type of fuse

I agree with k=115. We have to assume the circuit is in use when the fault develops.

 

[Deleted member 26818]

2.5/1.0 ring final on a BS 3036 fuse is a code 2 as it fails the adiabatic equation for this type of fuse

I agree with k=115. We have to assume the circuit is in use when the fault develops.

Are you suggesting that the 143 value for k is for circuits that are not in use when faults occur?

 

[nickblake]

looks like your'e returning to your normal self, nick.

oh yes , think i let things get to me a bit this week ,blaming my self for my accident too just got a bit down , ill be ok lol , dam stitches are starting to itch now argghhhh

yes I/P nothing wrong with BS 3036 boards , having said that if the spark fuse cover is missing then you have live exposed parts , wooden framed ones are a fire risk if a fault developes within the board ,and on this type of board is very common , and also they are open to mis use , how often have you found the incorrect wire in the fuse carriers 30 amp fuse wire in a 5 amp carrier , nice ,and when you take into consideration the correction factor for the fuse 0.725 then there is a possability you could blow the wiring due to the incorrect fuse wire , and yes we do joke about it but i have found nails in these carriers , and comming across it so many time is the reason i dislike them

 

[Deleted member 9648]

I dislike the old wylex 3036 boards but as long as it was intact and the fuse cover was in place..(very important)... I would not code it.
As far as the 1.0mm cpc goes it complied at the time it was installed and I've yet to see one damaged by a fault current....code 4 only for me.

 

[i=p/u]

can even throw tinfoil from ciggie pkt in them,

 

[i=p/u]

but for untrained people like myself, you do have to isolate before removing fuse, when i just started training i tried pull one out in mothers house , and couldnt ... isolated then could.she has 3x60amp with about 6 circuits on each. if i was to change could i get 1 board to accomadate all circuits.. ie whats the most ways you can get in domestic boards