Siemens 3RU2136-4HD1 SIRIUS Thermal Overload Relay, Class 10

Name: 3RU2136-4HD1
Brand: Siemens
SKU: 3RU2136-4HD1
Availability: LimitedAvailability
Author: Lube-Tech Lonnie

Specifications

Identification

3RU2136-4HD1 — Identification
Parameter	Value
Product brand name	SIRIUS
Product designation	thermal overload relay
Frame size (overload relay)	S2
Combinable contactor sizes	S2
Reference code (IEC 81346-2)	F

Protection & Trip

3RU2136-4HD1 — Protection & Trip
Parameter	Value
Overload current setting range	40 ... 50 A
Trip class	CLASS 10
Overload release type	thermal

Electrical (main circuit)

3RU2136-4HD1 — Electrical (main circuit)
Parameter	Value
Rated operational current	50 A
Poles (main circuit)	3
Rated operating frequency	50 ... 60 Hz
Rated insulation voltage (AC, pollution degree 3)	690 V
Rated value (AC-3e), max.	690 V
Rated surge withstand voltage	6 kV
Main current circuit	screw-type terminals
Power loss at rated current (hot)	15.6 W
Per pole	5.2 W

Auxiliary contacts

3RU2136-4HD1 — Auxiliary contacts
Parameter	Value
Auxiliary contacts: NO	1
Auxiliary contacts: NC	1
Auxiliary contacts: CO (changeover)	0
Auxiliary switch short-circuit protection (required fuse)	fuse gG: 6 A, quick: 10 A
Switching current at 24 V	2 A
Switching current at 60 V	0.3 A
Switching current at 110 V	0.22 A
Switching current at 120 V	3 A
Switching current at 125 V	0.22 A
Switching current at 220 V	0.11 A
Switching current at 230 V	2 A
Switching current at 400 V	1 A

Connection & Mounting

3RU2136-4HD1 — Connection & Mounting
Parameter	Value
Mounting / fastening method	stand-alone installation
Mounting position	any
Main-circuit connector arrangement	Top and bottom
Auxiliary/control circuit connection type	spring-loaded terminals
Removable aux./control terminal	No
Conductor cross-section: solid or stranded	2x (0.5 ... 2.5 mm²)
Conductor cross-section: finely stranded with ferrule	2x (0.5 ... 1.5 mm²)
Conductor range (AWG), main contacts	2x (18 ... 2), 1x (18 ... 1)
Conductor range (AWG), auxiliary contacts	2x (20 ... 14)

Environmental

3RU2136-4HD1 — Environmental
Parameter	Value
Operating temperature	-40 ... +70 °C
Storage temperature	-55 ... +80 °C
Transport temperature	-55 ... +80 °C
Relative humidity, operating	10 ... 95 %
Max. installation altitude	2 000 m

Mechanical

3RU2136-4HD1 — Mechanical
Parameter	Value
Width	55 mm
Height	105 mm
Depth	117 mm

Product details

Class 10 trip and what it means for your motor

The 3RU2136-4HD1 is a SIRIUS thermal overload relay — the bimetallic strip heater that sits between your contactor and the motor, watching for overcurrent. That's fast enough to protect a standard squirrel-cage induction motor during a locked-rotor event without nuisance-tripping on a normal start. The voltage ceiling matches the main contactor's rating, so you can run this on a 690 V distribution system without a separate voltage-reduction tap.

Panel fit and terminal details

Size S2 frame — 55 mm wide, 105 mm tall, 117 mm deep — mounts in any orientation on the DIN rail or directly to the panel backplate (cites:,). The normally-open contact closes when the relay trips, feeding a PLC input or alarm lamp.

Temperature tolerance and compliance

Temperature-compensated from -40 to +60 °C ambient, so the trip curve stays accurate whether the panel is in a hot mill or a cold warehouse (cites:). The substance-prohibitance declaration dates to October 15, 2014 — this relay meets RoHS and REACH requirements for that compliance window (cites:).

Frequently asked questions

Where can I buy the 3RU2136-4HD1 and get a price?

This relay is available through independent industrial distribution. Submit an RFQ for current pricing and lead time — availability is confirmed at quote time, not on the listing.

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

That note labels the auxiliary contact function — the integrated switch changes state when the bimetallic strip has tripped, providing a dry-contact signal to a PLC or alarm circuit (cites:,).