SG4 BASE
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4.3 EARTH CONNECTION
Safety light curtain units are preset for easy ground connection. A special compartment, positioned onto caps and
marked with the special symbol shown in
, allows connection with ground cable by means of an
additional screw coming with the equipment.
Fig 32 - Ground connection configuration
Ground connection configuration is the most common and guarantees the best immunity against electromagnetic
disturbances. Safety light curtain can function even without ground connection.
This condition has to be carefully evaluated according to the EMC disturbance immunity and necessary insulation
class considering the plant or entire system where the light curtain is installed.
The ground connection of the two units is not necessary for Class III, while the use of a duly-insulated low-
voltage feeder type SELV or PELV is compulsory. In this case, we recommend covering the earth symbol
present on the caps of the two units with a blank sticker.
The ground connection of the two units is compulsory for Class I, while the use of a duly-insulated feeder type
SELV or PELV is not compulsory but anyway recommended.
The following table is a summary of SG2-E electrical protections.
Electrical protections
Class I
Class III
Ground Connection
Compulsory
Not necessary
Ground connection symbol
Compulsory
Not necessary
Power supply by generators SELV / PELV
Recommended
Compulsory
