Max ZS

[Jako13!]

Does anyone know how to find the max ZS for these types of breakers? Thanks in advance guys.

 

[netblindpaul]

OEM data, & not a 7671 application if uk & not 60364 if eu.

 

[westward10]

That's a motor protection breaker and they normally provide overcurrent and short circuit protection I could be wrong here but Zs values aren't applicable as fault protection is provided elsewhere.

 

[Julie.]

Does anyone know how to find the max ZS for these types of breakers? Thanks in advance guys.

You do know they are motor protection devices not standard mcbs

It uses type 2 coordination between the starter and inbuilt magnetic trip.

The magnetic trip is 13x the maximum setting.

So if you have a 10A this would be 130A even if the actual motor current was set to say 8.3A.

Given 130A, the voltage and the standard correction factors, you can calculate the Zs

EDIT

seen the type of device has just been mentioned- x post!

These devices have inbuilt thermal characteristics targeted at motor protection rather than standard curves, and a direct magnetic trip, for overloads the curve trips the starter, but for large fault current the inbuilt breaker breaks the fault - this is type 2 coordination.

It's an Alan Bradley device BTW.