Siemens SIMOTICS T-1FW6 Configuration Manual page 493

Coupled motors
11.1 Operating motors connected to an axis in parallel
When the torque of an individual motor is not sufficient for the drive application, then it is
possible to distribute the required torque over 2 or more motors.
Mount the motors on the same axis. The motors are then mechanically coupled.
You have 2 possible variants for supplying the individual motors:
• Each motor is operated on its own Motor Module with its own encoder or using an
appropriate encoder signal splitting. This operation does not represent an electrical parallel
connection. The motors only operate together mechanically.
Options for generating encoder signals are:
– Several encoders
– Several measuring heads on one scale
– Hardware signal splitting
– Software signal splitting (TEC SERVCOUP)
• All of the motors are connected to the same Motor Modules. In this case, the article numbers
of all of the motors involved must be the same. The motors are then electrically connected
in parallel, and operate in the parallel mode.
For example, if you require information about optimally engineering or dimensioning drive
systems with torque motors operating in parallel, then contact technical support.
Note
Country-specific safety requirements for parallel operation
Country-specific safety requirements and regulations apply when connecting motors in parallel
at a Motor Module.
For example, in the US, for special motor protection, carefully comply with the requirements laid
down in standards NFPA 70 and NFPA 79.
Notes for parallel operation
The motor power cables must be the same length in order to ensure uniform current
distribution.
When operating several motors in parallel, you must accommodate additional motors and
cables. Plan the additional installation space required.
Add the rotor moment of inertia of each motor involved to the overall moment of inertia of
the axis.
1FW6 Built-in torque motors
Configuration Manual, 09/2022, A5E52220645B AA
11
491