Siemens SINAMICS S120 Commissioning Manual page 199

Checking the phase position, EMF phase U - EMF phase V - EMF phase W for parallel motors
The phase positions of the individual motors with respect to each other must match:
● EMF phase U motor 1 with EMF phase U motor 2
● EMF phase V motor 1 with EMF phase V motor 2
● EMF phase W motor 1 with EMF phase W motor 2
The deviation within a particular phase position may be a maximum of 10°.
Figure 2-58
Commissioning Manual
Commissioning Manual, (IH1), 01/2013, 6SL3097-4AF00-0BP3
2.13 Commissioning SIMOTICS 1FW6 built-in torque motors
Phase U motor 1 may not lag behind EMF phase U motor 2 by more than 10 °
Commissioning
197