Max Zs Values (pre-2015)




    Pre-amendment 3 version for looking up old Zs values for older installations, useful for checking if the installation complied with the max Zs values at the time of installation for installations designed before 2015. Old BS 7671 values.

    Maximum Zs Values
    Calculates maximum permitted Zs values for BS and BS EN devices, MCB's, RCBO's, Fuses and Manufacturer Specific Device values, specific values for RCD's in TT earthing systems, LV, REC Ze values....100% and 80% temperature adjusted values. (Pre-amendment 3)


    + BS EN Devices Zs values Calculator
    + Manufacturer specific device Zs values
    + REC Ze values
    + Calculate Zs values from known la ratings
    + Max Zs values for RCD's for TT earthing systems
    + 55 Volts single phase Zs values calculator
    + 63.5 Volts three phase Zs values calculator
    + RCD/RCBO Zs values calculator
    + BS fuses Zs values
    + 100% values
    + Temperature adjusted values
    + Zs values for 230v

    Tags: maximum zs permitted by bs 7671 , showing values , maximum zs permitted on 7.5 mcb , 17th edition maximum zs values , why is the max measured zs 80% of the max permitted , tnc-s earthing system ze and zs values , maximum zs values 17th edition , maximum permitted zs , maximum bs 7671 zs

    Users review

    from 35 reviews



    Users comments for Max Zs Values (pre-2015)

    Dan Bell

    by Dan Bell

    Jan 17, 2016  |  "Good"

    Now out of date as we paid for the this u shud update figures to incorporate amendment 3

    Lucian Toea

    by Lucian Toea

    Sep 30, 2015  |  "Great"

    Good app but needs updating

    tony head

    by tony head

    Sep 20, 2015  |  "Good"

    PLEASE update to Am3 values!

    Richard Hackett

    by Richard Hackett

    Sep 14, 2015  |  "Great"

    New zs values missing

    nick killick

    by nick killick

    Aug 20, 2015  |  "Good"

    Needs updating or it is useless

    Paul E

    by Paul E

    Jul 19, 2015  |  "Poor"

    Was great but now out of date as the values have changed with the recent amendment 3 of the regulations.