3RM13 motor starter with reversing functionality, electronic overload protection and safety-related shutdown

SIRIUS 3RM1 motor starters are compact devices 22.5 mm wide, combining a large number of functions in a single enclosure. They consist of combinations of relay contacts, power semiconductors (hybrid technology), and a solid-state overload relay for switching induction motors up to 3 kW (at 400 V) and resistive loads up to 10 A (at AC voltages to 500 V) under normal operating conditions.

The 3RM1 motor starters with overload protection with wide setting range are offered as direct-on-line starters and reversing starters and as versions with safety-related shutdown.

The 3RM1 motor starters are available in four versions:

? Function available

-- Function not available

Hybrid technology

The 3RM1s combine the benefits of semiconductor technology and relay technology. This combination is also known as hybrid technology. The hybrid technology in the motor starter is characterized by the following features:

• The inrush current is is conducted briefly via the semiconductors.
  Advantage: protection of relay contacts, long service life due to low wear
• The uninterrupted current is conducted via relay contacts.
  Advantage: lower heat losses compared with the semiconductor.
• Shutdown is implemented again via the semiconductor.
  Advantage: the contacts are only slightly exposed to arcs, and this results in a longer service life.

Functional density/space requirement

The 3RM1 motor starters combine the functions of direct-on-line/reversing starting, electronic overload protection and safety-related shutdown in a single device, without changing in size.

For simple applications (such as starting and reversing three-phase loads with overload protection), motor starter combinations of power contactors and a solid-state overload relay, for example, can be replaced by a 3RM1 device. The more functions are required, the more devices can be replaced. The surface area required for each motor starter in the control cabinet is reduced by values of 20 to 80 %.

In the case of assemblies and grouped feeder units there are further advantages.

Wiring outlay

By combining various functions in a single device, wiring outlay is reduced. The greater the scope of functions, the greater the saving in wiring. Savings can be made in:

• Mains supply line and motor feeder, and device connections in the main circuit
• Wiring of the reversing contactor assembly in the main circuit, if required
• Contact locking if there is a reversing contactor assembly in the control circuit
• Control cables for coil terminals in the control circuit

These savings reduce the time required for the wiring itself. At the same time, they reduce both the risk of wiring errors and the amount of testing required after control cabinets have been completed.

Configuration and stock keeping

The wide setting range of the electronic overload release (up to 1:5) reduces the cost of keeping stocks and the considerations involved in configuration where the actual motor current to be expected is concerned. Compared with protection equipment with thermal overload protection, only 3 versions are now required, instead of 17, to cover a current range of 0.1 to 7 A when using the 3RM1.

Connection methods

The 3RM1 is available with screw terminals and spring-type terminals or mixed connection method (screw terminals for the main circuit and push-in terminals for the control circuit).

Screw terminal for removable terminal (3-pole) for 3RM1 motor starters and 3SK1 safety relays

Spring-type terminal as push-in connection for removable terminal (3-pole) for 3RM1 motor starters and 3SK1 safety relays

Push-in connection method

Push-in connections are a form of spring-type connection allowing fast wiring without tools for rigid conductors or conductors equipped with end sleeves.

Fine-stranded or stranded conductors with no end finishing are wired using a screwdriver (with a 3.0 x 0.5 mm blade).

As with other spring-type terminals, a screwdriver is also required to release the conductor. The same tool as above can be used for this purpose.

The advantages of the push-in terminals are found, as with all spring-type terminals, in speed of assembly and disassembly and vibration-proof connection. There is no need for the checking and tightening required with screw terminals.

Innovative enclosure concept

1 Terminals

The terminals are easy to replace, optionally with screw or spring-type connections:

• 1,2,3: 3-pole terminals for the control circuit
• 4,5,6: 2-pole terminals for the main circuit

2 Labeled cover caps

To access the top and bottom terminals, the covers must be opened. To facilitate orientation, there is a laser inscription on the inside of the caps for the connections.

3 Sealable cover

To protect against unauthorized access, a sealable cover can be attached.

4 LED status display

You can see at a glance from the LED status display whether operation is normal or whether faults exist. This allows fast, selective commissioning. Faults can be quickly traced and even more quickly corrected.

5 Rotary coding switch

The current of the motor to be monitored can be set using the rotary coding switch. When a motor is replaced, it can be adapted within the respective wide setting range. This means that in most cases the motor starter does not have to be replaced.

6 TEST/RESET button

Acknowledgment in the event of a fault:
1. Resetting in the event of overload
2. Performance of the test function
3. Switching from manual to auto reset

7 Data matrix code

The data matrix code enables simple and fast scanning in of article numbers and serial numbers.

8 Width

The width of only 22.5 mm saves space in the control cabinet, and is thus cost-effective, especially in plants with a large number of small motors up to 3 kW.

Innovative enclosure concept for the SIRIUS 3RM1 motor starters

Safety-related shutdown/safety integration

Thanks to the redundant design of the main circuit and internal monitoring, safety-related shutdown in accordance with SIL 3 / PL e is possible by shutting down the control supply voltage with 3RM11 Failsafe and 3RM13 Failsafe motor starters, or in the case of the 24 V DC control voltage version, by shutting down the control inputs. Additional safety relays are not required in the main circuit.

Combination of four SIRIUS 3RM1 Failsafe motor starters with SIRIUS 3SK1 safety relay to allow safety-related collective disconnection of connected motors

3RM1 motor starters are ideal for combining with the 3SK1 safety relay (see "Safety Technology" > "SIRIUS 3SK1 Safety Relays"). They can be combined by means of:

• conventional wiring
• a special device connector

This makes it very simple to shut down connected motors collectively. The wiring, and ultimately the shutting down of the control supply voltage in Emergency-Stop situations, is performed via the device connector. There is no further need for complex looping of the connecting cables.

Feedback to the control system

The electronic output in the 24 V DC control voltage version of the 3RM10 and 3RM12 motor starters allows the status of the connected motor to be reported to the higher-level control system. If the motor starter is controlled via inputs IN1 to 2, once the motor has been switched on and has started up correctly the output "OUT" is set.

Infeed system for the main circuit

The 3RM19 infeed system available as an accessory for the main circuit with three-phase busbars allows fast, virtually error-free wiring of motor starters on the mains connection side and may reduce the number of short-circuit protective devices.

Article No. scheme

¹⁾ Mixed connection method: Control circuit realized as push-in spring-type terminal and main circuit as screw terminal