Three-phase infeed system (3RM19 three-phase busbar system)

The system permits an easy, time-saving and safe means of feeding two or more 3RM1 motor starters. It can only be used for motor starters with screw terminals in the main circuit.

The maximum summation current must not exceed 25 A. The primary infeed is connected via a three-phase infeed terminal.

The busbars are available in three lengths, with 2, 3 or 5 sockets. More than 5 devices can be connected by clamping the connection tags of a second busbar rotated by 180°.

The three-phase busbars are finger-safe but empty connection tags must be fitted with covers.

3RM19 infeed system with three-phase infeed terminal: In the above example, two three-phase busbars (5-pole busbars) rotated through 180° allow up to 9 3RM1 motor starters to be connected. Contact with the unused connection tags in unoccupied positions is prevented safely by the covers.

Device connectors for the control circuit

The device connectors for 3RM1 motor starters (only 24 V DC control supply voltage) reduce the outlay for cabling by looping through the control supply voltage. The device connectors can be snapped onto a standard mounting rail or fixed to a level mounting panel using screws.

Device connectors with 3RM1 motor starter

Using the device connectors exclusively for feeding in the control supply voltage

By using device connectors, a maximum of 5 motor starters can be supplied with 24 V DC control supply voltage. This requires the control supply voltage to be applied to the A1 and A2 terminals of only one motor starter.

Device daisy chain connectors can be be used for gaps between two motor starters. Device termination connectors terminate a group.

Using the device connectors for safe group shutdown

In combination with the 3RM11 and 3RM13 Failsafe motor starters, the device connector can also be used for safety-related shutdown. For this application, groups of no more than 5 Failsafe motor starters can be connected using a device connector, and the group must be terminated with a terminating connector. Removing the control voltage supply from the first motor starter will safely shut down the whole group.

Safe group shutdown can be implemented particularly easily in conjunction with 3SK safety relays. In this case, up to 5 motor starters can be directly connected to 3SK safety relays via the device connector and then safely shut down.

Ideal connection: Combination of four SIRIUS 3RM1 Failsafe motor starters with SIRIUS 3SK1 safety relay