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Siemens 3RU2126-1JJ0 — Overload Relays

Siemens 3RU2126-1JJ0 SIRIUS Thermal Overload Relay, Class 10

MPN3RU2126-1JJ0

Siemens SIRIUS thermal overload relay, 3RU2126-1JJ0, Size S0, Trip Class 10, rated 690 V, 4 kW at 400 V, contactor mounting.

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

3RU2126-1JJ0 — Identification
ParameterValue
Product brand nameSIRIUS
Product designationthermal overload relay
Frame size (overload relay)S0
Combinable contactor sizesS0
Reference code (IEC 81346-2)F
3RU2126-1JJ0 — Protection & Trip
ParameterValue
Overload current setting range7 ... 10 A
Trip classCLASS 10
Overload release typethermal
3RU2126-1JJ0 — Electrical (main circuit)
ParameterValue
Rated operational current10 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 circuitRing cable lug connection
Power loss at rated current (hot)6.6 W
Per pole2.2 W
3RU2126-1JJ0 — 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
3RU2126-1JJ0 — Connection & Mounting
ParameterValue
Mounting / fastening methodContactor mounting
Mounting positionany
Main-circuit connector arrangementTop and bottom
Auxiliary/control circuit connection typering terminal lug connection
Removable aux./control terminalNo
3RU2126-1JJ0 — 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
3RU2126-1JJ0 — Mechanical
ParameterValue
Width45 mm
Height85 mm
Depth85 mm

Product details

SIRIUS thermal overload relay, Size S0, Class 10

The Siemens 3RU2126-1JJ0 is a SIRIUS thermal overload relay, Size S0, with Trip Class 10 — meaning it trips within 10 seconds at 7.2× the set current, matching the typical startup profile of standard AC induction motors. Rated for 690 V and delivering 4 kW at 400 V, 5.5 kW at 500 V, and 7.5 kW at 690 V, it is sized for motor protection in 50/60 Hz circuits. The thermal bimetallic release compensates from -40 to +60 °C, so the trip curve stays accurate across the panel environment.

Mounts directly to the contactor via the fastening method specified; no separate DIN-rail base required. Accepts any mounting position, and the auxiliary switch is integrated — no add-on block needed for the trip signal. Main circuit connections use ring cable lugs (M4 screw), so the wiring stays secure under vibration. Dimensions: 85 mm wide, 45 mm deep, 85 mm tall — fits the standard S0 footprint.

Frequently asked questions

What compliance documentation does 3RU2126-1JJ0 carry?

The substance prohibitance date is 10/01/2009, indicating RoHS compliance. The relay is part of the SIRIUS family, which typically carries CE, UL, CSA, and IEC certifications (confirm specific marks with the datasheet).

MPN
3RU2126-1JJ0