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Siemens 3RU2126-4EB1 — Overload Relays

Siemens 3RU2126-4EB1 SIRIUS Thermal Overload Relay, CLASS 10

MPN3RU2126-4EB1
Active

Siemens SIRIUS 3RU2126-4EB1 thermal overload relay, CLASS 10, size S0, 690 V rated, 15 kW at 400 V, screw terminals.

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

3RU2126-4EB1 — Identification
ParameterValue
Product brand nameSIRIUS
Product designationthermal overload relay
Frame size (overload relay)S0
Combinable contactor sizesS0
Reference code (IEC 81346-2)F
3RU2126-4EB1 — Protection & Trip
ParameterValue
Overload current setting range27 ... 32 A
Trip classCLASS 10
Overload release typethermal
3RU2126-4EB1 — Electrical (main circuit)
ParameterValue
Rated operational current32 A
Poles (main circuit)3
Rated operating frequency50 ... 60 Hz
Rated insulation voltage (AC, pollution degree 3)690 V
Rated value (AC-3e), max.690 V
Rated surge withstand voltage6 kV
Main current circuitscrew-type terminals
Power loss at rated current (hot)9.6 W
Per pole3.2 W
3RU2126-4EB1 — Auxiliary contacts
ParameterValue
Auxiliary contacts: NO1
Auxiliary contacts: NC1
Auxiliary contacts: CO (changeover)0
Auxiliary switch short-circuit protection (required fuse)fuse gG: 6 A, quick: 10 A
Switching current at 24 V2 A
Switching current at 60 V0.3 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
3RU2126-4EB1 — Connection & Mounting
ParameterValue
Mounting / fastening methodstand-alone installation
Mounting positionany
Main-circuit connector arrangementTop and bottom
Auxiliary/control circuit connection typescrew-type terminals
Removable aux./control terminalNo
Conductor cross-section: solid or stranded2x (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)
Conductor range (AWG), main contacts2x (16 ... 12), 2x (14 ... 8)
Conductor range (AWG), auxiliary contacts2x (20 ... 16), 2x (18 ... 14)
3RU2126-4EB1 — Environmental
ParameterValue
Operating temperature-40 ... +70 °C
Storage temperature-55 ... +80 °C
Transport temperature-55 ... +80 °C
Relative humidity, operating10 ... 95 %
Max. installation altitude2 000 m
3RU2126-4EB1 — Mechanical
ParameterValue
Width45 mm
Height97 mm
Depth95 mm

Product details

It protects motors against overload and phase failure by monitoring the current draw and tripping the associated contactor when the thermal model reaches the trip threshold.

Rated insulation voltage is 690 V, with power ratings of 15 kW at 400 V, 18.5 kW at 500 V, and 30 kW at 690 V. The AC-3e maximum voltage is also 690 V, so it's suited for 400 V and 690 V motor circuits common in European and export panels. The auxiliary switch is integrated, saving a separate aux block on the contactor. The thermal overload release is ambient-compensated from -40 to +60 °C, so the trip curve stays stable across the panel's internal temperature range. Terminals accept 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²) solid or stranded wire, with M4 main contact screws. The screwdriver spec is Pozidriv PZ2 with a 5 to 6 mm shaft diameter — standard for panel builders.

Deployment context

The S0 frame size is a common footprint across the SIRIUS family, so panel cutouts and wiring layouts for the contactor side are standard. The integrated auxiliary switch eliminates one wiring step during panel assembly.

Frequently asked questions

What does the note 'for message Tripped' mean on this relay?

The note indicates that the auxiliary contact position labeled 'Tripped' is used to signal a trip condition to a PLC or indicator lamp. It is a standard auxiliary contact on the integrated switch.

What is the depth of the 3RU2126-4EB1?

The depth is 95 mm, with a width of 45 mm and height of 97 mm.

Where can I buy the 3RU2126-4EB1 and how is it quoted?

This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time — no stock count or price is listed here.

Will the 3RU2126-4EB1 drop into a panel designed for a 3RV1011-1HA10?

No — the 3RV1011-1HA10 is a circuit breaker, not a thermal overload relay. The 3RU2126-4EB1 is a separate overload relay that mounts to a contactor, so the panel layout and wiring differ. They are not drop-in interchangeable.

MPN
3RU2126-4EB1