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Siemens 3RU1126-1DD0 — Overload Relays

Siemens 3RU1126-1DD0 SIRIUS Thermal Overload Relay, CLASS 10

MPN3RU1126-1DD0

Siemens SIRIUS thermal overload relay, 3RU1126-1DD0, size S0, CLASS 10, screw-type terminals, contactor mounting, 690 V AC-3 max, IP20 front, ATEX.

Sourced new & surplus through independent channelsAuthenticity-screened · ESD-safe packingListing updated Jul 2026

Specifications

3RU1126-1DD0 — Identification
ParameterValue
Product brand nameSIRIUS
Product designationthermal overload relay
Frame size (overload relay)S0
Combinable contactor sizesS0
3RU1126-1DD0 — Protection & Trip
ParameterValue
Trip classCLASS 10
3RU1126-1DD0 — Electrical (main circuit)
ParameterValue
Poles (main circuit)3
Rated insulation voltage (AC, pollution degree 3)690 V
Rated surge withstand voltage6 kV
Main current circuitscrew-type terminals
3RU1126-1DD0 — Auxiliary contacts
ParameterValue
Auxiliary contacts: NO1
Auxiliary contacts: NC1
Auxiliary switch short-circuit protection (required fuse)fuse gL/gG: 6 A, quick: 10 A
Switching current at 24 V1 A
Switching current at 110 V0.22 A
Switching current at 120 V3 A
Switching current at 125 V0.22 A
Switching current at 220 V0.11 A
Switching current at 230 V2 A
Switching current at 400 V1 A
3RU1126-1DD0 — Connection & Mounting
ParameterValue
Mounting positionwith vertical mounting surface +/-135° rotatable, with vertical mounting surface +/- 45° tiltable to the front and back
Conductor cross-section: solid2x (0.5 ... 2.5 mm²)
Conductor cross-section: finely stranded with ferrule2x (0.5 ... 1.5 mm²)
3RU1126-1DD0 — Environmental
ParameterValue
Operating temperature-20 ... +70 °C
Storage temperature-55 ... +80 °C
Transport temperature-55 ... +80 °C
Relative humidity, operating100 %
Shock resistance8g / 10 ms
3RU1126-1DD0 — Mechanical
ParameterValue
Width45 mm
Height97 mm
Depth96 mm
3RU1126-1DD0 — Specifications
ParameterValue
Type Of ProtectionDMT 98 ATEX G 001

Product details

The screw-type terminals on the main circuit accept 2x (0.5... 2.5 mm²) solid or 2x (0.5... 1.5 mm²) finely stranded with ferrule, covering most panel wiring up to about 5.5 kW motor circuits.

Mounts on a vertical surface with ±135° rotation and ±45° tilt forward/backward — flexible for tight panel layouts. The S0 footprint is 45 mm wide × 97 mm tall × 96 mm deep, so it fits standard 45 mm DIN-rail spacing when paired with its contactor. Side clearance of 6 mm to adjacent devices is sufficient for heat dissipation; no forced derating needed at the rated 5.7 W power loss in hot operating state. Shock-rated to 8g for 10 ms — fine for most industrial panels but not for high-vibration mobile equipment without additional damping.

Carries ATEX protection type DMT 98 ATEX G 001 for use in potentially explosive gas atmospheres. Surge voltage resistance rated at 6 kV, which covers installation category III in 400 V networks. Relative humidity tolerance of 100% during operation means condensation inside the enclosure is not a derating factor.

Frequently asked questions

What is the closest functional second-source for 3RU1126-1DD0?

The closest functional peer is the 3RT6023-1AB00 contactor that this relay mounts onto — they share the S0 frame and screw-terminal pattern. The relay itself is the overload protection half of that contactor pair; no direct second-source relay exists from another brand with the same footprint and CLASS 10 curve without rewiring.

MPN
3RU1126-1DD0