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What are the maximum earth loop impedance Zs values for the iKQ mcb's?

Please find the list of the iKQ mcb Zs values at 230V.

 In order to comply with BS7671 Amendment 3: 2015 the figures in the chart should be multiplied by Cmin = 0.95
Calculation for Zs Earth loop impedance
Zs - is the maximum earth fault loop impedance.
Uo - is the nominal voltage to earth (for a 400V 3 phase system this is 230V).
Ia - is the current causing the operation of the circuit breaker in less than 0.4 seconds.
Cmin - is the minimum voltage factor to take account of voltage variations depending on time and place, changing of transformer taps and other considerations. (Cmin = 0.95)
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