max zs table in the osg

[Lighting]

Hi all sorry for this silly question but i cant seem to find the max Zs table for a 10A BS88-2 Fusein the osg. I can find it in the BGB table 41.4
10A = 7.19 ohms and i know to multiply it by 0.8 (7.19 x 0.8 = 5.75) for rule of thumb but i would like to find the right table in the osg

 

[Octopus]

Not all the bgb is in the osg!

 

[Farmelectrics]

Use the value in the reqs but don't forget to apply the 80% factor

 

[Andy78]

Are you sure you are looking at the right table in the BGB ? table 41.4 is for 5 seconds disconnection.

 

[Pete999]

Hi all sorry for this silly question but i cant seem to find the max Zs table for a 10A BS88-2 Fusein the osg. I can find it in the BGB table 41.4
10A = 7.19 ohms and i know to multiply it by 0.8 (7.19 x 0.8 = 5.75) for rule of thumb but i would like to find the right table in the osg

Page 122 ???? I think thats right

 

[Lighting]

Are you sure you are looking at the right table in the BGB ? table 41.4 is for 5 seconds disconnection.

Hi I'm using table 41.4 has it is for street lighting.

 

[Lighting]

Page 122 ???? I think thats right

Hi Peter999 page 122 is table c1 Application of cables for fixed wiring.

 

[Pete999]

Hi Peter999 page 122 is table c1 Application of cables for fixed wiring.

Are you using the latest OSG? the yellow one?

 

[telectrix]

yellow? i'm still on the red one. it's the same electricity whatever osg you use.

 

[Pete999]

yellow? i'm still on the red one. it's the same electricity whatever osg you use.

Page 122 table B3 not sure if that is what the op is after

 

[Lighting]

Are you using the latest OSG? the yellow one?

no I'm still using the green one

 

[Pete999]

no I'm still using the green one

Flgged mine of flea bay

 

[Engineer54]

Use the value in the reqs but don't forget to apply the 80% factor

To be honest, i've never used this 80% factor and probably never will now!!
Can't see the point of why they need to mess around with proven values that have served electrical installations well for literary donkey's years...

 

[Jonspark]

To be honest, i've never used this 80% factor and probably never will now!!
Can't see the point of why they need to mess around with proven values that have served electrical installations well for literary donkey's years...

i know your not in Britain, but if you were, surely you'd have to work to BS7671 requirements?

wouldn't not meeting these requirements constitute a C2

 

[telectrix]

the figures are given in BS7671 without the 80% correction factor. these are what i use. in winter when we are measuring @3 deg.C, not 20, should we then apply another correction?

 

[Jonspark]

the figures are given in BS7671 without the 80% correction factor. these are what i use. in winter when we are measuring @3 deg.C, not 20, should we then apply another correction?

dont know. just thought you had to apply appendix 14

 

[davesparks]

i know your not in Britain, but if you were, surely you'd have to work to BS7671 requirements?

wouldn't not meeting these requirements constitute a C2

A C2 would be the code applied to a potentially dangerous fault found on an EICR, there is no such thing on an EIC.
If he has used values other than those in the books and recorded this deviation as part of the installations documentation then as long as the testing proves that the circuit is within those values there is no problem. Bs7671 is not the be all and end all of electrical installation!

 

[Engineer54]

Perhaps i should of also pointed out that the typical Zs values measured on our projects will meet and exceed anything that's presently deemed as max Zs values...

 

[Jonspark]

A C2 would be the code applied to a potentially dangerous fault found on an EICR, there is no such thing on an EIC.
If he has used values other than those in the books and recorded this deviation as part of the installations documentation then as long as the testing proves that the circuit is within those values there is no problem. Bs7671 is not the be all and end all of electrical installation!

doesn't an earth loop impedance value greater than that required warrant a potentially dangerous fault, ergo C2?

which other values apart from the manufactures are there?

 

[Jonspark]

Perhaps i should of also pointed out that the typical Zs values measured on our projects will meet and exceed anything that's presently deemed as max Zs values...

and so they should!