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Siemens 3RU2126-1FJ0 — Overload Relays

Siemens 3RU2126-1FJ0 SIRIUS Thermal Overload Relay, Class 10

MPN3RU2126-1FJ0

Siemens SIRIUS thermal overload relay, 3RU2126-1FJ0, Size S0, Trip Class 10, rated 690 V, 50-60 Hz, contactor-mount, with integrated auxiliary switch.

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

3RU2126-1FJ0 — Identification
ParameterValue
Product brand nameSIRIUS
Product designationthermal overload relay
Frame size (overload relay)S0
Combinable contactor sizesS0
Reference code (IEC 81346-2)F
3RU2126-1FJ0 — Protection & Trip
ParameterValue
Overload current setting range3.5 ... 5 A
Trip classCLASS 10
Overload release typethermal
3RU2126-1FJ0 — Electrical (main circuit)
ParameterValue
Rated operational current5 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
3RU2126-1FJ0 — 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
3RU2126-1FJ0 — 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
3RU2126-1FJ0 — 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
3RU2126-1FJ0 — Mechanical
ParameterValue
Width45 mm
Height85 mm
Depth85 mm

Product details

Rated for 690 V and 50-60 Hz operation, it mounts directly onto a contactor (fastening method: contactor mounting), saving panel space versus a standalone enclosure. The thermal release design compensates for ambient temperature between -40 and +60 °C, so the trip point stays accurate across the enclosure's internal heat rise. Motor power ratings it can protect: 1.5 kW at 400 V, 2.2 kW at 500 V, and 4 kW at 690 V. The auxiliary switch is integrated — no add-on block needed for the trip-indication signal.

Size S0 means it fits the standard S0 contactor footprint — direct snap-on or screw-clamp mounting to the contactor, no additional DIN-rail bracket needed. The ring-cable-lug connection for the main circuit handles M4 ring terminals. Mounting position is any, so horizontal or vertical panel layouts work without derating the trip curve. Dimensions: 45 mm wide × 85 mm high × 85 mm deep — fits within a standard 45 mm module slot. The auxiliary switch uses a Pozidriv PZ2 screwdriver tip with a 5-6 mm shaft diameter.

Auxiliary contact ratings and the 'Tripped' message

The integrated auxiliary switch carries the trip-indication signal. Its contact ratings vary by voltage: 2 A at 24 V AC, 3 A at 120 V AC, 2 A at 230 V AC, 1 A at 400 V AC, and 0.22 A at 125 V DC. The Note for message 'Tripped' on the component line refers to the state when the relay has operated — the auxiliary contact changes state to signal a trip condition to the PLC or annunciator.

Operating temperature range: -40 to +70 °C. Storage and transport: -55 to +80 °C. Temperature compensation active from -40 to +60 °C. The substance prohibition date of 10/01/2009 aligns with RoHS compliance (lead-free and other restricted substances). MTTF with high demand rate: 2,280 years.

Frequently asked questions

What is the 3RU2126-1FJ0's 'Note for message Tripped'?

The note indicates the state when the thermal overload relay has operated — the integrated auxiliary switch changes state to signal a trip condition.

What are the motor power ratings for the 3RU2126-1FJ0?

It protects motors rated 1.5 kW at 400 V, 2.2 kW at 500 V, and 4 kW at 690 V, all at 50-60 Hz.

How does the 3RU2126-1FJ0 compare to the 3RU2116-1FC1?

Both are SIRIUS S0-frame thermal overload relays with Class 10 trip curves. The 3RU2126-1FJ0 is the higher-current variant in the same physical footprint — it drops into the same contactor mounting and panel cutout without rewiring, but the current setting range differs. Verify the motor FLA falls within the 3RU2126-1FJ0's adjustment range before substituting.

Where can I buy the 3RU2126-1FJ0 and get current pricing?

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

MPN
3RU2126-1FJ0