This XPSCM safety module is for monitoring of single-beam photo-electric sensors and has a built-in "muting" function. It meets the requirements of PL c/Category 2 conforming to EN/ISO 13849-1.and SILCL1 conforming to EN/IEC 61508 and EN/IEC 62061. Used in conjunction with XU2S single-beam photo-electric sensors (periodically tested), it establishes a category 2 light curtain conforming to IEC/EN 61496 parts 1 and 2.