Type 4 stablok breakers

[markc17]

Hi all, after some clarifcation really

Carrying out some work in a building, sub divided into Federal electric stablok boards.
All of the ring main circuits in the whole building are protected by 30 amp stablok breakers..type 4.. of which there are hundreds. The conduit is acting at the earting and this is buried floor and ceiling in concrete.
On a recent PIR, some of the EFLI's are coming in 'too high'. It seems that the company that tested have simply used the figures from the regs for a type d 60898 breaker 32 amp - 0.36 and compared it against this.
I cannot find any information on type 4's anywhere so did the calcs (x 50).. and the result is much lower than this and would infact put most of the circuits out.
I did however come across a discussion on a thread, in which somebody said they had the data for a 30A federal 3871 type 4, and that the Zs was 0.64. ( i can only imagine that the lower rated tripping current was used in the calcs)
I am slightly confused, and would love some clarification, and also any information on FE stablok breakers if there is any going...

Many thanks,

Mark

 

[Engineer54]

If at all possible get shot of those Fed elec Boards and breakers, they were out and out crap when they first come on the market in the UK and they are STILL crap today!! Stab-lok type MCB's can be a real pain for many reasons, especially the American Fed Elec, W House, G Elec, black bakelite type MCB's. Why anyone would use type 4 breakers on Ring circuits is beyond me, but about par for the course in the States for outlet circuits!!

 

[markc17]

I know... awful circuit breakers.. unfortunately, not an option to rewire the whole building at the moment so just need some clarification on the breakers themselves. I have been finding evidence on the net of other people experiencing the same thing.. whole boards full of type 4 breakers so there must have been a reason for this that i am missing.

I cant seem to find any information on Federal Electric UK.. somebody said they may have been bought out by Schneider..

 

[Guest111]

I know... awful circuit breakers.. unfortunately, not an option to rewire the whole building at the moment so just need some clarification on the breakers themselves. I have been finding evidence on the net of other people experiencing the same thing.. whole boards full of type 4 breakers so there must have been a reason for this that i am missing.

I cant seem to find any information on Federal Electric UK.. somebody said they may have been bought out by Schneider..

[h=2]Federal Electric Ltd., Wolverhampton[/h]

Street:	Fordhouse Road, Bushbury
Zip Code/City:	WV10 9ED Wolverhampton, West Midlands
Phone:	01902 303300
Website:	www.schneider-electric.co.uk

 

[Flanders]

I was told that you might as well use a switch as opposed to stab lock as they take some tripping out, I have not seen any official data on this only what has been thrown around building sites in idle chat. Give Schnieder Technical a call they may have some data on them for you. Otherwise you could start a rolling program changing 1 DB at a time

 

[Engineer54]

I know... awful circuit breakers.. unfortunately, not an option to rewire the whole building at the moment so just need some clarification on the breakers themselves. I have been finding evidence on the net of other people experiencing the same thing.. whole boards full of type 4 breakers so there must have been a reason for this that i am missing.

I cant seem to find any information on Federal Electric UK.. somebody said they may have been bought out by Schneider..

No, they were and still are just a crap system. I believe those Fed Elec only came with type 3 and 4 breakers, i could be wrong, but i've never seen a fed elec type 1 or type 2 breaker.

 

[markc17]

Managed to get the original circuit breaker application data from Federal Electric... Zs for a type 4 is much higher than stated for a 3871 in the regs.. not sure i understand why but makes allowance for the hundred or so breakers on this system.

 

[Flanders]

Managed to get the original circuit breaker application data from Federal Electric... Zs for a type 4 is much higher than stated for a 3871 in the regs.. not sure i understand why but makes allowance for the hundred or so breakers on this system.

Could you share this information with us ? It might help gets some Thanks on the board

 

[markc17]

absolutely.. i had a nightmare trudging the net trying to find stuff on this.. in the end i spoke to an old timer working in the tech department who very kindly took the time to look it up for me.... will have to wait till monday as i am just leaving work.. there is a few pages of data so i will have to work out how to make it availablle some how..if anybody knows how i can attach an adobe file on here i will do it....

 

[clarke24]

absolutely.. i had a nightmare trudging the net trying to find stuff on this.. in the end i spoke to an old timer working in the tech department who very kindly took the time to look it up for me.... will have to wait till monday as i am just leaving work.. there is a few pages of data so i will have to work out how to make it availablle some how..if anybody knows how i can attach an adobe file on here i will do it....

Hi mark, id be greatful if you could email the data to me at [email protected]. Thanks

 

[Engineer54]

Managed to get the original circuit breaker application data from Federal Electric... Zs for a type 4 is much higher than stated for a 3871 in the regs.. not sure i understand why but makes allowance for the hundred or so breakers on this system.

If that's the case then these breakers do not comply with BS 3871 Type 4 breakers. That is the whole point of having a BS typing for MCB's!!

 

[GLENNSPARK]

If that's the case then these breakers do not comply with BS 3871 Type 4 breakers. That is the whole point of having a BS for MCB's!!

seems the americans themselves arn`t too keen on these stabloc`s either:

Sta Block Breaker Question - Electrical - Contractor Talk

 

[GLENNSPARK]

here:

federal stab-lok disconnection times.

For .4 sec disconnection times:

5=2.14

10=1.28

14=.85

20=.64

25=.51

30=.42

40=.32

50=.25

60=.21

80=.16

100=.12

5 second dis times:

5=6.18

10=3.71

15=2.47

20=1.85

25=1.48

30=1.23

40=.92

50=.74

60=.61

80=.46

100=.37

 

[Silly Sausage]

seems the americans themselves arn`t too keen on these stabloc`s either:

Sta Block Breaker Question - Electrical - Contractor Talk

Has Tony not introduced you to the wonders of CR4 yet?

 

[GLENNSPARK]

Has Tony not introduced you to the wonders of CR4 yet?

yep....been on it..
not recently though....

 

[markc17]

If that's the case then these breakers do not comply with BS 3871 Type 4 breakers. That is the whole point of having a BS typing for MCB's!!

Well, in this case i still am better off using the manufacturers data rather than comparison with a type d 3871. I have recommended a rolling plan of board changes, which is going to take a few years, but atleast i have done everything in my power to have the correct information to put down. At the end of the day, they pass according to manufacturers data, which atleast explains why they were put in in the first place. Now down to them.

 

[markc17]

The times i have are different to those, even with rule of thumb.. can i ask where you got this info?

 

[Engineer54]

Well, in this case i still am better off using the manufacturers data rather than comparison with a type d 3871. I have recommended a rolling plan of board changes, which is going to take a few years, but atleast i have done everything in my power to have the correct information to put down. At the end of the day, they pass according to manufacturers data, which atleast explains why they were put in in the first place. Now down to them.

How can manufactures data of MCB's marked up as ''Type 4'' differ from those set out in the British Type 4 Standard for god's sake?? You have a minimum and maximum tripping time/current characteristic where the maximum is generally taken for Zs purposes. MCB's are manufactured to meet a specific trip Type, under British standards, Not the other way round!!

Changing these DB's is a good plan, Personally i wouldn't even a thank You for any of those old Yank based Fed Elec board or breakers

 

[netblindpaul]

E54,
If you look into this, in detail, you will, I suspect find, this is why FE are no more!...

 

[Engineer54]

E54,
If you look into this, in detail, you will, I suspect find, this is why FE are no more!...

Now THAT would make a lot of Sense!! ...lol!!