What it is and where it lands
The Siemens 3RU1116-1CB0-ZX95 is a SIRIUS thermal overload relay in the S00 frame size — the smallest footprint in the SIRIUS family, sized for compact motor control centers and DIN-rail panels where every millimeter of width counts. It's a three-pole relay with a CLASS 10 trip characteristic, meaning it will open the circuit within 10 seconds at 7.2× the set current — standard protection for standard-start induction motors driving pumps, fans, and conveyors. The IP20 front protection keeps fingers out of the terminal area inside the panel; it's not rated for washdown environments, so keep it behind a gland plate or enclosure door.
Mounting and wiring — the practical bits
This relay mounts directly onto a contactor via the contactor mounting interface — no DIN rail bracket needed if you're pairing it with a SIRIUS contactor of matching S00 frame. Screw terminals on both main and auxiliary circuits: main terminals accept 2× (0.5…1.5 mm²) solid or 2× (0.75…2.5 mm²) solid, plus the AWG equivalents (2× 20…16 and 2× 18…14). Auxiliary terminals take 2× (20…16) and 2× (18…14) AWG. Mounting position is flexible — vertical surface with ±135° rotation or ±45° tilt front-to-back — which helps when you're cramming this into a tight corner of a retrofit panel. Clearance to neighboring devices: 0 mm upwards, forwards, backwards, and downwards; 6 mm at the side. That zero-gap top and bottom means you can stack contactor-overload pairs without wasting rail space.
What the ratings mean in the field
Shock resistance rated at 8g for 10 ms — that's enough to survive a forklift bump into the panel or a moderate seismic event without nuisance tripping. Surge voltage withstand of 6 kV gives the relay decent immunity against switching transients on the motor circuit; it's not a full surge protector, but it won't fail on the first spike from a contactor dropout. Operating temperature range -20 to +70 °C covers most indoor industrial environments; storage and transport range -55 to +80 °C means it can sit in an unheated warehouse or truck without damage. Power dissipation per pole is 1.9 W — three poles means about 5.7 W total heat inside the enclosure. Factor that into your panel thermal budget if you're running multiple relays in a sealed box.
Lifecycle and sourcing reality
It carries ATEX approval (DMT 98 ATEX G 001) for use in potentially explosive atmospheres, plus the usual CE marking under the Low Voltage Directive. RoHS compliance date is noted as July 1, 2006, so it's fully RoHS-compliant.