3RU2136-4HB1

What type of device is this?

This is a thermal overload relay from the Siemens SIRIUS 3RU2 range, designed for motor protection in three-phase control systems. It monitors motor current and trips when overload conditions are detected.

What current range does it cover?

The adjustable overload setting range is 40 to 50 A, allowing it to be set to match the rated full-load current of the connected motor.

What trip class does it use?

It is a Class 10 thermal overload relay, meaning it is intended for standard motor starting applications where the overload relay should trip relatively quickly under sustained overload conditions.

Can it be reset manually and automatically?

Yes. The relay provides manual and automatic reset functionality, giving users flexibility depending on the control panel design and operational preference.

What size contactor is it intended to work with?

It is an S2 size overload relay and is intended for use with compatible S2 contactor arrangements or as a stand-alone mounted device.

How is it mounted?

The unit is specified for stand-alone installation, making it suitable for panel layouts where the overload relay is installed separately rather than directly mounted beneath a contactor.

What type of terminals does it use?

It uses screw-type terminals for both the main current circuit and the auxiliary/control circuit. The main circuit connections are arranged at the top and bottom of the device.

What auxiliary contacts are included?

It includes one normally closed auxiliary contact for contactor disconnection and one normally open auxiliary contact for trip indication. There are no changeover auxiliary contacts.

What operating voltage is it rated for?

The main circuit has a rated operating voltage of up to 690 V AC, with a rated operational current of 50 A.

What motor power ratings are associated with it?

For AC-3 and AC-3e duty, the relay is rated for motor applications up to 22 kW at 400 V, 30 kW at 500 V, and 45 kW at 690 V.

What is the ambient operating temperature range?

The specified operating temperature range is -40 °C to +70 °C, with temperature compensation from -40 °C to +60 °C.

What are its approximate dimensions?

The relay measures approximately 105 mm high, 55 mm wide and 117 mm deep, making it a compact S2-frame motor protection component.

What degree of front protection is provided?

The front of the device is rated IP20 to IEC 60529 and is finger-safe for vertical contact from the front.

What conductor sizes can be used on the main terminals?

For the main contacts, the relay accepts solid or stranded conductors up to 1 x 50 mm² or 2 x 35 mm², depending on the connection arrangement. For finely stranded conductors with end processing, it accepts up to 1 x 35 mm² or 2 x 25 mm².

What tightening torque is required for the terminals?

The specified tightening torque is 3 to 4.5 N·m for the main screw terminals and 0.8 to 1.2 N·m for the auxiliary screw terminals.