The Siemens 3RU1116-1JB0-ZW97 is a SIRIUS-brand thermal overload relay in Size S00, designed for motor protection in control panels. The ATEX certification (DMT 98 ATEX G 001,) qualifies it for use in potentially explosive gas atmospheres, so it can be specified into Ex-rated motor starter assemblies.
Size S00 footprint: 45 mm wide, 87 mm tall, 78 mm deep. Mounts directly onto the contactor — no DIN rail required for the relay itself, though the contactor typically snaps onto a DIN rail. Clearance requirements are minimal: 0 mm upwards, forwards, backwards, and downwards; only 6 mm at the side is needed. This means it can be packed tightly against adjacent devices in a multi-starter row, saving rail space. Wire sizes: solid 2×(0.5…1.5 mm²) and 2×(0.75…2.5 mm²); stranded with ferrule 2×(0.5…1.5 mm²) and 2×(0.75…2.5 mm²); AWG equivalents 2×(20…16), 2×(18…14), and 2×12 for main contacts, and 2×(20…16), 2×(18…14) for auxiliary contacts.
Auxiliary contact ratings and thermal dissipation
The built-in auxiliary contact (likely a 1 N/O + 1 N/C configuration, though not explicitly stated) is rated across common control voltages: 1 A at 24 V, 0.22 A at 110 V, 3 A at 120 V, 0.22 A at 125 V, 0.11 A at 220 V, 2 A at 230 V, and 1 A at 400 V. The 3 A at 120 V rating is notably higher than the others — likely a resistive or AC-15 pilot-duty rating — so if your control circuit is 120 VAC, you have more headroom. Power dissipation per pole is 2.2 W, so the total 3-pole dissipation is 6.6 W. In a densely packed panel with multiple starters, this heat adds up — factor it into your enclosure thermal calculation, especially if the ambient during operation can reach +70 °C.
