What it is and what it protects
The Siemens 3RU1116-1FB1 is a SIRIUS thermal overload relay in the Size S00 frame, designed for three-phase motor protection in control panels. It trips on a Class 10 curve — meaning it disconnects within 10 seconds at 7.2× the set current, fast enough to protect standard induction motors during a stall or locked-rotor event without nuisance tripping on normal starts. It mounts standalone on a vertical surface with ±135° rotation and ±45° tilt front/back, giving panel builders flexibility to fit it into tight enclosures or odd-angle subpanels. The front is IP20 — touch-safe for the operator side — but the relay itself is not sealed against washdown; keep it inside a cabinet. Each pole dissipates 2.2 W under load, so in a multi-relay enclosure you need to account for the cumulative heat. At 45 mm wide, three of these side-by-side consume 135 mm of DIN rail — plan your gutter space accordingly.
Wiring and termination
Main and auxiliary circuits use screw-type terminals. The main contacts accept 1× 20–16 AWG, 1× 18–14 AWG, or 1× 12 AWG solid/stranded. Auxiliary contacts accept 2× 20–16 AWG or 2× 18–14 AWG. For finely stranded wire with ferrules, the range is 2× (0.5–1.5 mm²) and 2× (0.75–2.5 mm²). The auxiliary contact ratings cover the common control voltages: 1 A at 24 V, 3 A at 120 V, 2 A at 230 V, and 1 A at 400 V AC. At 110 V and 125 V the contact is rated 0.22 A — likely a DC rating for those voltages, so verify the load type before wiring a DC solenoid or contactor coil through it.
Where it fits and what it talks to
This relay lives in the SIRIUS S00 family, the smallest frame size. It carries ATEX approval (DMT 98 ATEX G 001). Surge voltage resistance is rated at 6 kV, which aligns with IEC 60947-1 overvoltage category III for industrial control panels. The reference code per IEC 81346-2 is F (protective device), which helps when tagging the device in an EPLAN or similar schematic.