Coupling devices are used to secure electrical isolation between logic and load.
ENW-E12: Level Sensor Monitor, power supply 230 V AC
KRAS-M6/21, 1 changeover contacts, 24 V AC/DC
11061305:KRA-M4/1 LC, 1 normally open contact (SPST-NO), 24 V AC/DC
CR-810-DUO:Motor Protection Relay via PTC Output