mcbs?

[redface]

dose anyone know what the bs number is for some old brown trips and max fault current and max zs additions.
or a websight that would tell me about all trips and mcbs

thank you

 

[telectrix]

which trips do you mean?

 

[Guest123]

Crabtree C50's maybe???

 

[malcolmsanford]

Are they BS 3871 and what type are they if they are. A typical type 2 is rated at 7 times it's trip capacity. So a 10 amp would be 230/70 = 3.29 ohms. There is a section in the OSG but unfortunately I left mine in the office, but I'm sure one of the lads will tell, if they are BS 3871

 

[Guest123]

If they are C50's the KA rating differed between those with white markings and those with yellow ones.

There is a thread on here about them somewhere, I'll see if I can find it.

Can you confirm the are the C50 breakers first???

 

[redface]

well they are a lot bigger than the bs 3871 s that im used to and they are brown but they may still be 3871 but these brown trips are in a old comercial building i have only seen smaller ones in domestic and other idears?

 

[Guest123]

Do they look like this.......

 

[redface]

and they have no info atall on them apart from rateing 32a 5a etc

 

[redface]

thats tham thanx mate real help

 

[Engineer54]

Are you talking about those old bakerlite Square D type breakers ??

Edit....

haha!! those crap American style breakers...

 

[redface]

but what is the max ka and bs no. and caculation for max zs

 

[malcolmsanford]

They are not like these GE ones


Wholesale Thql1 Ge Mini Circuit Breaker Mcb - Buy China Wholesale Thql1 Ge Mini Circuit Breaker Mcb from Chinese Wholesalers | Nobodybuy.com

 

[Guest123]

As I said, if they have white markings they are rated to 3KA, the newer ones with yellow markings are rated to 4.5KA.

BS 3871 max loop impedance values can be found in the OSG.

 

[redface]

thanks mate so they have a low ka so that is crap and they are 3871s then

 

[Guest123]

You can still buy the newer ones (yellow markings) and these are manufactured to BS EN 60898