60942-7 Max Zs Tables

60947-2 Max Zs Charts

60947-2 Max Zs Charts

The maximum Zs tables and charts for BS EN 60947-2 MCCB’s varies between manufactures and specific to the MCCB part number, then again depending on the settings of the actual MCCB device. Due to the many variables there isn’t a quick Zs calculation for 60947-2 MCCB (moulded case circuit breaker) or ACB (air circuit breaker) protection devices.

In order to obtain the correct Zs value for ACB’s and MCCB’s you need to refer to the manufacturers data table for the specific device part number and specific device settings.

We are aware on how time consuming it can be trying to locate the Zs value for a BS EN 60947-2 MCCB or ACb, therefore we designed and developed the Max Zs Values App which includes all common protective devices such as MCB’s, Fuses and RCBO’s along with a selection of manufacture specific MCCB’s, the Max Zs Values app is available on iPhone, iPad and Android

Zs Values for 60947-2 MCCB’s

We have a number 60947-2 Zs charts from different MCCB manufacturers. We have included the Max Zs charts for 60947-2 MCCB’s in an Max Zs Values App.


Maximum permitted Zs for BS EN 60947-2 Protective Devices

The maximum permitted Zs values for 60947-2 protective devices vary between different manufacturers, for instance 60947-2 Merlin Gerin Zs values are different to 60974-2 Eaton Zs values and 60947-2 Square D max Zs values are different to 60947-2 Dorman Smith and ABB max Zs values for example.

BS EN 60947-2 Zs Tables

Tables and charts for MCCB’s and ACB’s are normally available to download from the manufacturer’s website, on occasions you maybe able to phone the manufacturer who can point you in the right direction. ACB | MCCB | 60947-2

​We have included some BS EN 60947-2 Zs charts within our Max Zs Values App where you can look up the Zs chart for the MCCB listed by the part number such as NSX250 or TMD160D. The MCCB Zs charts are grouped by manufacture for easy to find look up Zs charts for MCCB’s.


An extensive database of maximum Zs values.

100% + 80% values
MCB’s & RCBO’s

Download for iOS  Download for Android