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Siemens 3RB3123-4RB0 — Overload Relays

3RB3123-4RB0 - Siemens

MPN3RB3123-4RB0
Active

Overload relay 0.1...0.4 A Electronic For motor protection Size S0, Class 5...30 Contactor mounting Main circuit: Screw Auxiliary circuit: Screw Manual-Automatic-Reset Internal ground fault detection

$385.57Ref. price · indicative, final on quote
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

3RB3123-4RB0 — Identification
ParameterValue
Product brand nameSIRIUS
Product designationsolid-state overload relay
Frame size (overload relay)S0
Combinable contactor sizesS0
Reference code (IEC 81346-2)F
3RB3123-4RB0 — Protection & Trip
ParameterValue
Overload current setting range0.1 ... 0.4 A
Trip classCLASS 5E, 10E, 20E and 30E adjustable
Overload release typeelectronic
3RB3123-4RB0 — Electrical (main circuit)
ParameterValue
Rated operational current0.4 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)0.1 W
Per pole0.03 W
3RB3123-4RB0 — 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
Switching current at 24 V2 A
Switching current at 60 V0.55 A
Switching current at 110 V0.3 A
Switching current at 120 V4 A
Switching current at 125 V0.3 A
Switching current at 220 V0.11 A
Switching current at 230 V3 A
3RB3123-4RB0 — Connection & Mounting
ParameterValue
Mounting / fastening methodContactor mounting
Mounting positionany
Main-circuit connector arrangementTop and bottom
Auxiliary/control circuit connection typescrew-type terminals
Removable aux./control terminalYes
Conductor cross-section: solid1x (0.5 ... 4 mm²), 2x (0.5 ... 2.5 mm²)
Conductor cross-section: solid or stranded1x (0,5 ... 4 mm²), 2x (0,5 ... 2,5 mm²)
Conductor cross-section: finely stranded with ferrule1x (0.5 ... 2.5 mm²), 2x (0.5 ... 1.5 mm²)
3RB3123-4RB0 — Environmental
ParameterValue
Operating temperature-25 ... +60 °C
Storage temperature-40 ... +80 °C
Transport temperature-40 ... +80 °C
Relative humidity, operating10 ... 95 %
Max. installation altitude2 000 m
Shock resistance15g / 11 ms
3RB3123-4RB0 — Mechanical
ParameterValue
Width45 mm
Height87 mm
Depth84 mm
MPN
3RB3123-4RB0