200A OPD 3 phase short circuit capacity

[buttonmoon]

Hi all

Any of you know whether there is a table or other source (other than waiting on hold for ages or opening the fuse covers)to find the short circuit capacity for a 200A main fuse in a 3 phase 40 year old supply?
Also is it going to be BS88 or 1361?

 

[malcolmsanford]

If they have tags then it is likely to be BS 1361 and if they are bullet fuses then BS 88

If they are most likely to be the old BS 88-2-2 or BS88-6 they could be 3000+ for 0.1 seconds but that type of fuse would most likely be for distribution and could be as low as 1200.

If they are 1361s then you really need to be contacting the manufacturers for their SC ratings

 

[Plonker 3]

Attachment is for BS1361 fuses.

 

[Chr!s]

Id expect it to be a BS 88, 80 kA

 

[Chr!s]

If they have tags then it is likely to be BS 1361 and if they are bullet fuses then BS 88

If they are most likely to be the old BS 88-2-2 or BS88-6 they could be 3000+ for 0.1 seconds but that type of fuse would most likely be for distribution and could be as low as 1200.

If they are 1361s then you really need to be contacting the manufacturers for their SC ratings

Hi Malc

I thought 1361 stopped at 100 amp?

 

[Plonker 3]

Hi Malc

I thought 1361 stopped at 100 amp?

Looks like that, having just looked at the PDF I have posted.

 

[Plonker 3]

A couple of bits of information I have found

Trading Depot - Lawson Fuses Application Data

http://www.fmccrustel.ru/pdf/BS88/BS88.pdf

 

[malcolmsanford]

Hi Malc

I thought 1361 stopped at 100 amp?

Hi Chr!s I think you could get 125amps at one time mate ................ and that is why I said most likely BS 88 either the 2.2 or the 6.

Saying that I have never seen a 1361 over 100amp but I'm sure at the pit they used 125 amps, but I stand corrected mate or they may have been to a different standard

I know the old Regs only went up to 100amp 1361 but there is something in my mind saying 125, but there again there is a lot in my mind that is rubbish lol

 

[buttonmoon]

I just found a bunch of catalogues and they all seem to be bs88 for 400/415v 200A
http://www.neweysonline.co.uk/newey...ion_&_Control_Switch_&_Fusegear_Technical.pdf

 

[buttonmoon]

Oh and 80kA Short circuit capacity

Thanks for your help guys

 

[buttonmoon]

This new EICR business is a bit of a pain.

 

[trebor]

Hi all

Any of you know whether there is a table or other source (other than waiting on hold for ages or opening the fuse covers)to find the short circuit capacity for a 200A main fuse in a 3 phase 40 year old supply?
Also is it going to be BS88 or 1361?

We only used BS88 J type fuses in any service over 100A the BS1361 cartridge fuses being used for domestic and small services ie 60A and 100A

Iv1e just dug down to the bottom of my old toolbox and found a 200A which is rated at 80kA

As a point of interest no one would know what fuse rating is in a cut out as this was not recorded on our paperwork, so a 4ooA service head could have fuses from 400A down depending on the declared load at the the time of metering

 

[buttonmoon]

We only used BS88 J type fuses in any service over 100A the BS1361 cartridge fuses being used for domestic and small services ie 60A and 100A

Iv1e just dug down to the bottom of my old toolbox and found a 200A which is rated at 80kA

As a point of interest no one would know what fuse rating is in a cut out as this was not recorded on our paperwork, so a 4ooA service head could have fuses from 400A down depending on the declared load at the the time of metering

Do you mean that the only way to know is to open the head?

 

[trebor]

Do you mean that the only way to know is to open the head?

That is up to the individual, all i would say is that any data enquiry to the dno results in a standard answer which sometimes could be correct and a lot of times will be wrong,so I guess the answer is yes, but with caution, if the cut out is plastic not too bad, but if it is the ironclad green ISCO then be very careful as carriers are porcelain and sometimes the thumbscrews are missing leaving a live part exposed

 

[topquark]

Do you mean that the only way to know is to open the head?

Yes, give the the DNO for your area a ring and see if they have a process for you to follow.