This new SPD is intended for to be used in situations where the SPD cannot be connected to equipotential bonding or earthing conductor. It is to be mounted onto signal lines and its internal connection has only in diferential mode (line – line) only, serving both as coarse and fine protection of lines running at voltage level up to 24 V.
Concerning its technical execution the SPDs contain a replaceable module which, even when removed, does not make the signal line to be interrupted. DMG-024-V/1-4FR1-DIF can be used for two cores till four cores signal lines.
More information see online catalog: here