19.1ka psc reading on a 2 bed small house!

[ch1cki]

Any ideas??

 

[londonlec]

So a message for some sparks, more experienced than moi!...

I've never seen this scenario, so how would you get around it?
All I can think of is a 100amp BS1361 (33kA) protecting the installation after the suppliers main fuse, then into your CU as normal.

 

[Guest 004]

So a message for some sparks, more experienced than moi!...

I've never seen this scenario, so how would you get around it?
All I can think of is a 100amp BS1361 (33kA) protecting the installation after the suppliers main fuse, then into your CU as normal.

BS88 fuse, has 80Ka breaking capacity

 

[londonlec]

Would my method ensure compliance?

I think the most I have ever seen was 10/11kA. Block of flats, tranny on site.

Edit:

Do the smaller rating BS88s still have 80kA breaking cap?

 

[ch1cki]

The best way is to steak it!

 

[londonlec]

The best way is to steak it!

Steak and chips?

 

[ch1cki]

why would you want anything higher, its only 19.1? Earth rod, RCBO'S, done!

 

[Deleted member 9648]

Am I missing something?....how is an earth rod going to make any difference to a PSC of 19.1ka?

 

[IQ Electrical]

Am I missing something?....how is an earth rod going to get over a PSC of 19.1ka?

Because someone isn't sure of how to arrive at a PFC value...

Ben, what would your prospective short circuit current be with an earth rod installed?

 

[IQ Electrical]

Fuse back-up protection to 16 kA is a mandatory test for the incoming device, protective devices, connections, and any other item in a Consumer Unit complying with BS EN 60439-3 Annex ZA & BS 5486-13.

This is a conditional rating, as the conditions specifically relate to the use of an upstream BS 88-3 (formerly BS 1361) 100 A fuse.​

 

[pushrod]

I've never seen this scenario, so how would you get around it?
.

Too high a pfc could be a down side of unnecessarily upgrading meter tails. Lot of people seem to think if they are not 25mm² then they must be upgraded, but there is a down side.

Not getting round it as such, but possibly preventing it from happening.

 

[Guest 004]

Am I missing something?....how is an earth rod going to make any difference to a PSC of 19.1ka?

maybe he was thinking of disconnecting the main earth, and replacing it with the earth rod

 

[i=p/u]

main fuse would cover 33KA

 

[i=p/u]

But your mcbs would be knackered

 

[IQ Electrical]

main fuse would cover 33KA

No, the conditional rating is 16kA, check post 24.

 

[IQ Electrical]

maybe he was thinking of disconnecting the main earth, and replacing it with the earth rod

But how would that make any difference to PSSC?