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Siemens 3RU1126-1KB0-ZW97 — Overload Relays

Siemens 3RU1126-1KB0-ZW97 SIRIUS Thermal Overload Relay, CLA

MPN3RU1126-1KB0-ZW97

Siemens SIRIUS thermal overload relay, 3RU1126-1KB0-ZW97, CLASS 10 trip, S0 frame, screw-type terminals, ATEX certified.

Source DocumentedChannel stated on listing & quote
Condition PhotosReal unit photos / video on request
WhatsApp AnswersFast human replies for machine-down parts
Worldwide DispatchDHL/FedEx — transit quoted per order
Independent China distributor & sourcing agent· Listing updated Sep 2026

Specifications

3RU1126-1KB0-ZW97 — Identification
ParameterValue
Product brand nameSIRIUS
Product designationthermal overload relay
Frame size (overload relay)S0
Combinable contactor sizesS0
Reference code (IEC 81346-2)F
3RU1126-1KB0-ZW97 — Protection & Trip
ParameterValue
Overload current setting range9 ... 12.5 A
Trip classCLASS 10
3RU1126-1KB0-ZW97 — 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
Power loss at rated current (hot)6.6 W
Per pole2.2 W
3RU1126-1KB0-ZW97 — Auxiliary contacts
ParameterValue
Auxiliary contacts: NO1
Auxiliary contacts: NC1
Auxiliary contacts: CO (changeover)0
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
3RU1126-1KB0-ZW97 — Connection & Mounting
ParameterValue
Mounting / fastening methodContactor mounting
Mounting positionwith vertical mounting surface +/-135° rotatable, with vertical mounting surface +/- 45° tiltable to the front and back
Auxiliary/control circuit connection typescrew-type terminals
Removable aux./control terminalNo
Conductor cross-section: solid2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)
Conductor cross-section: finely stranded with ferrule2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)
3RU1126-1KB0-ZW97 — Environmental
ParameterValue
Operating temperature-20 ... +70 °C
Storage temperature-55 ... +80 °C
Transport temperature-55 ... +80 °C
Relative humidity, operating100 %
Max. installation altitude2 000 m
Shock resistance8g / 10 ms
3RU1126-1KB0-ZW97 — Mechanical
ParameterValue
Width45 mm
Height97 mm
Depth96 mm
3RU1126-1KB0-ZW97 — Specifications
ParameterValue
Type Of ProtectionDMT 98 ATEX G 001

Product details

Mounting is via direct contactor attachment (fastening method: contactor mounting), so it snaps onto the matching SIRIUS contactor without additional DIN-rail space. The relay carries DMT 98 ATEX G 001 certification, meaning it is approved for use in potentially explosive gas atmospheres — a requirement for Zone 1 or Zone 2 motor circuits in chemical, oil-and-gas, or grain-handling plants. The front panel is IP20 rated, finger-safe per IEC 60529, so it can sit on an open panel door without additional guarding.

If your motor has a longer acceleration time (high-inertia loads like centrifuges or large flywheels), you would typically step up to CLASS 20 or CLASS 30 — but that is a different relay, not this one. The S0 frame size is the mid-range in the SIRIUS family, physically fitting contactors in the same S0 envelope. Clearance requirements: 0 mm upward, forward, backward, and downward; 6 mm at the side. That zero-clearance top and bottom means you can stack contactors directly without leaving an air gap, but the 6 mm side gap must be maintained for heat dissipation. The solid/stranded wire range is 2× (0.5…1.5 mm²) and 2× (0.75…2.5 mm²) for the auxiliary contacts, with AWG equivalents of 2× (20…16) and 2× (18…14). For the main circuit, the same ranges apply. This covers most control wiring up to 2.5 mm² — standard for motor control centers. Auxiliary contact ratings: at 24 V it switches 1 A; at 120 V, 3 A; at 230 V, 2 A; at 400 V, 1 A.

Environmental and electrical robustness

Relative humidity during operation can hit 100% — no derating needed for condensing environments, which is common in washdown or outdoor installations. Shock resistance is 8g for 10 ms, adequate for most industrial vibration profiles (pumps, conveyors, compressors). Surge voltage withstand is rated at 6 kV, which matches the impulse voltage category for 400 V industrial circuits (overvoltage category III per IEC 60664). This means the relay can handle switching transients from contactor coils and motor starts without internal flashover. Heat dissipation per pole is 2.2 W. For a three-pole relay at full load, that is 6.6 W total — modest, but in a densely packed panel with multiple relays side by side, the cumulative heat can raise ambient temperature above the 70 °C limit. The 6 mm side clearance is the critical spacing to keep that heat manageable.

Frequently asked questions

Where can I buy 3RU1126-1KB0-ZW97?

This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time.

What compliance documentation does this relay carry?

It carries DMT 98 ATEX G 001 certification for explosive gas atmospheres. The substance prohibitance date per RoHS/REACH is listed as 07/01/2006. The reference code per IEC 81346-2 is F (protective device).

What is the closest functional alternative to 3RU1126-1KB0-ZW97?

The 3RU2116-1FC1 is a peer in the SIRIUS family but belongs to a different size/frame. The 3RU1126-1KB0-ZW97 is an S0 frame with CLASS 10 trip; the 3RU2116-1FC1 is a different frame size. They are not direct drop-in replacements without verifying the mounting interface and current range.

MPN
3RU1126-1KB0-ZW97