Max ZS for BS 3871's

[trebor]

Does anybody know where i can find the max 100% ZS values for Type 1,2 and 3 BS 3871 mcbs? The OSG only has the 80% ones and just wondered if there was anywhere that had the 100% one so i dont have to re-calculate it.
Any help much appreciated

Try this link, then 4th question down

Periodic Inspection of Existing Domestic and Similar Installations

 

[coxy]

Hi I have a 15th edition of the regs which gives disconnection times - The question I think is why are these times not in the 17th edition ?? even as a suplument ?? I have always used the ratings from the 15th edition of the regs ??

 

[ian.settle1]

Hi I have a 15th edition of the regs which gives disconnection times - The question I think is why are these times not in the 17th edition ?? even as a suplument ?? I have always used the ratings from the 15th edition of the regs ??

No you can not use the 15th or 16th values as these are based on the voltage being 240v and not 230v as is now used under harmonisation.

 

[Graeme Harrold]

jimmer just times the 80% by 1.2 to get 100%

des you can still buy 3871 mcbs crabtree c50 memshield 1 and others
why do you say they should be replaced with 60898?

You need to multiply the 80% value by 1.25 to get a more accurate 100% value

 

[davos010]

There is a table on the inside page of the NICEIC certificates stating all the max Zs ratings for 3871's 88's 1361's 1362's and 3036's.

 

[scotsparky]

There is a grweat table in the current OSG with 3871,and 60898 MC Max ZS in it.

 

[patchman21]

just googled this to check and

17th Edition Maximum Ze & Zs Values

states "BS7671 does not give maximum Zs values for BS 3871 mcb's"

If you have the disconnection time, device manufacturer (if not i can use generic) and rating I can use my software (single cable) to find the values.

Hi guys, James here with first post!


Does anyone know the max permitted Zs for a 32A type 4 3871 mcb?

Many thanks to anyone who can help, cheers


James.

5s = 1.0034
0.4s = 0.5134

Taken from Single Cable 17th eddition generic values