Connecting The Motors In Parallel - Siemens SINAMICS S120 Function Manual

Function modules

7.10 Connecting the motors in parallel

7.10 Connecting the motors in parallel
Description
For easy commissioning of group drives (a number of identical motors operating on one
power unit) in control modes servo and vector, the number of parallel-connected motors can
be entered in STARTER or in the parameter list (p0306: Number of parallel connected
motors).
An equivalent motor is computed internally depending on the number of motors specified.
The motor identification run determines the data for an equivalent motor. Motors connected
in parallel can also operate on an encoder (on the first motor).
Note
For information about parallel connection of Motor Modules, please refer to section "Parallel
connection of power units".
Features
● Up to 20 motors connected in parallel can be operated on one converter system.
● It is not permissible to connect synchronous or reluctance motors in parallel.
● The original motor data set (p300 ff.) is not modified. It is merely the data set transfer to
● The motor identification routine also works on parallel connections. Supplementary
● The rotating measurement function also works if the motors can rotate without distance
● The cable lengths for motors connected in parallel must be as symmetrical as possible to
Commissioning via STARTER
Parameter p0306 is assigned in a STARTER commissioning screen. When subsequent
parameters are set, p0306 is included in the calculation of the current limit (p0640) and the
reference current (p2002).
Parameter p0306 has a value range of 1 to 20 and is MDS-dependent.
To create a parallel connection of motors, the appropriate motor must be selected from the
screen list, checkbox "Parallel connection motor" enabled and the number of motors
included in the parallel connection entered in the "Number" dropdown box. This display and
input facility is available only for vector drives. Parallel connections of motors for servo drives
can be configured with the expert list (parameter p0306).
318
the closed-loop control which is organized according to the number of parallel-connected
motors.
conditions for successful motor identification: The motors are working on the same load
and are thus coupled.
limit. Uneven loading of the motors or a high degree of gear backlash will negatively
affect the accuracy of the rotating measurement result.
afford the most even possible distribution of current among individual motors.
Function Manual, (FH1), 10/2008, 6SL3097-2AB00-0BP5
Drive functions