What the Trip Class and size mean for motor protection
The 3RU2116-0HJ0: That suits standard motor start-ups where the inrush doesn't stretch beyond a few seconds; a Class 20 or 30 would be for high-inertia loads like fans or crushers. Size S00 means it mates with the matching S00 contactor frame — the relay snaps directly onto the contactor without extra DIN-rail space. The 45 mm width and 70 mm depth keep the assembly tight in a crowded enclosure.
Wiring and auxiliary contact ratings
Main circuit termination uses ring cable lugs — you torque the M3 screws on the contactor's main terminals. That's a solid connection for motor feeders, no push-in or spring cage here. The integrated auxiliary switch has a note "for message 'Tripped'" — meaning it signals the relay's tripped state, not the contactor's coil status. That covers most PLC input modules and indicator lamps.