CZSR8403-1AR1B is a safety relay control module, suitable for DO signal isolation and conversion in SIS system, with 1 normally open (NO) contact and 1 normally closed (NC) contact, reserved terminals are convenient to realize fast offline Proof Test Test. The fuse bin on the panel is preset with 5A fuse protection. Users can quickly replace damaged fuses. The internal circuit adopts triple redundancy technology, meet the requirements of the IEC61508 standard, and the security integrity level can reach sil3.