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Max Zs Values

By Pro Certs Software Ltd

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Calculate maximum permitted Zs values (earth loop impedance) as per BS7671, also includes temperature adjusted values.

Using the picker wheel select the protective device (fuse's, MCB's, RCBO's) and device rating to calculate the maximum permitted Zs value for your selected device.

+ BS7671 Amendment 3 2015 values
+ BS EN device's
+ Fuse's
+ MCB's
+ RCBO's
+ RCD's
+ Ze + R1+R2 = Zs
+ 100% values
+ 80% values
+ 0.4 second disconnection times
+ 0.2 second disconnection times
+ 5 second disconnection times

Search for 'Pro Certs Software' in the app store for our other electrical apps designed for the electrical industry aimed at electricians and electrical engineers.

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What's New in Version 2.1

V 2.0 - 27/09/2015: Updated Zs values for BS 7671 amendment 3 2015.
V 2.1 - 28/09/2015: Fixed share bug.


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Max Zs Values
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This app is designed for both iPhone and iPad
  • NIS 6.90
  • Category: Reference
  • Updated:
  • Version: 2.1
  • Size: 8.3 MB
  • Language: English
  • Developer:

Compatibility: Requires iOS 6.0 or later. Compatible with iPhone, iPad, and iPod touch.

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