Functional earth

Functional earth 1:

Installation with protective conductor connection

When installing electrical systems and components, the protective conductors must be connected first. They must be disconnected last when uninstalling.

Depending on the magnitude of the leakage currents, observe the following regulations for the implementation of the protective conductor connection:

    • Minimum requirement for protective conductor: KU value of 4.5
    • The minimum requirement for leakage currents: IL < 10 mA; KU = 6 for IL > 10 mA

    Value

    Explanation

    KU

    Variable for the classification of safety-related types of failure for protection against dangerous shock current and excessive heating

    KU = 4.5

    Achieved in relation to interruption:
    With permanently connected protective conductor connection
    ≥ 1.5 mm2
    With protective conductor connections ≥ 2.5 mm2 via connector for industrial plants according to IEC 60309-2

    KU = 6

    Achieved in relation to interruption:
    With permanently connected conductors ≥ 10 mm2; the type of connection and routing must comply with the standards applicable to PE conductors

    Functional earth 2:
    Screw the cable lug of the ground strap [1] to the functional earth connection [4] of the tile using a screw [2] and washers [3]
    Functional earth 3:
    Screw the cable lug of the ground strap [1] to the machine bed [4] using a screw [2] and washers [3]

    There are two options for the functional earthing of your system: