mccb max Zs ??

[dasersc]

Anyone know of or where to find Max permitted Zs for mccb`s (60947-2) please?

 

[tony mc]

I think you may need to consult the manufaturers for any applicable info as it's not in the regs.

A quick google may throw up some tech info for you.

 

[oldtimer]

Does this help


View attachment Circuit Braeker Info.[1].pdf

 

[Goody]

Anyone know of or where to find Max permitted Zs for mccb`s (60947-2) please?

The max trip current (Im) for this type of MCCB is 800 A and if the nominal voltage (Uo) is 230 v, then max Zs will be Uo/Im = 0.2875 ohms.

 

[chronyx]

Cheers, found this on Google and was stuck on a test sheet I'm typing up

 

[IQ Electrical]

Anyone know of or where to find Max permitted Zs for mccb`s (60947-2) please?

You are always safer using manufacturers data on these devices, many have adjustable characteristics on the curve.

 

[Engineer54]

You are always safer using manufacturers data on these devices, many have adjustable characteristics on the curve.

Exactly!! .... The data sheet that comes with these MCCBs will generally give you this information. If it doesn't, then it will direct you to a web site page that does. Generally all MCCBs will have different Max Zs even those of the same manufacturer, between different model numbers in the same frame size....

 

[zoom213]

im struugling to find max zs readings for siemens breakers if anyone could help, cheers

 

[Engineer54]

im struugling to find max zs readings for siemens breakers if anyone could help, cheers

Struggle no more, contact Siemens with the exact MCCB details, and they will furnish you with the information!!!

As i have stated above, Even MCCB's of the same manufacturer and frame size will/can have very different Max Zs requirements...

 

[ste77]

Amtech have a handy device called "single cable" which has almost all MCCB max Zs values for anyone that is interested

 

[Engineer54]

Amtech have a handy device called "single cable" which has almost all MCCB max Zs values for anyone that is interested

Interesting!! ...Any chance of showing a list of Schneider MCCB's with their max Zs values. I'll check them against my home made data base. ...Iv'e a feeling this list isn't going to be too accurate to be honest!!

 

[ste77]

Its not in simple tabulated layout form its has selection process where you choose the make, family, type, protection and rating then it calculates it for you. But if you have yours in tabulated form i'll happily check them against what amtech says.

 

[Guest55]

Interesting!! .. I'll check them against my home made data base. ...Iv'e a feeling this list isn't going to be too accurate to be honest!!

you mean its not precise to 4 decimal places ??
tut tut , next you'll be rounding pi down to 3
;-D

 

[Engineer54]

you mean its not precise to 4 decimal places ??
tut tut , next you'll be rounding pi down to 3
;-D

You may scoff, but there are significant differences in MCCB maximum Zs values attached to different types, even within the same type and frame sizes and families of the same manufacturer. Were not talking about type tested MCB's here... lol!!