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Due to RMS continuous product improvement policy this information is subject to change without notice. 1S20_User_Guide/Iss C/10/07/23
Introduction
The 1S20 monitors either one, two or three 1S30 optical sensors to detect the presence of an arcing
fault within Metal Clad air insulated switchgear.
The 1S20 provides 2 zones or common Arc Fault trip outputs and continuously supervises the optical
sensors to ensure maximum availability of the Arc Fault Protection scheme.
Upon detection of an arc the 1S20 can either initiate or directly trip circuit breakers to affect fault
clearance.
1S20 Variants
The 1S20 is available in several voltage ranges, mounting arrangements and either 2 or 3 optical point
sensor variants.
Mounting Arrangements
1S20 - #A#
Panel mount or surface mount
1S20 - #C#
Panel mount or surface mount with DIN rail kit supplied
1S20 - #B#
Surface mount only
1S20 - #D#
Surface mount only with DIN rail kit supplied
Sensor Variants
1S20 - ##A
Maximum of two 1S30 sensors connected
1S20 - ##B
Maximum of three 1S30 sensors connected
