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
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)
In order to comply with BS7671 Amendment 3: 2015 the figures in the chart should be multiplied by Cmin = 0.95
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)