Bosch rexroth MBT, Manual

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For selection of the motor encoder to achieve the required accuracy, the fol‐
lowing points have to be taken into consideration:
●
Speed range of the motor
● Speed range of the encoder
● Encoder resolution/accuracy
● Compatibility with controller
Measuring principle
Absolute encoder The advantages of absolute encoder systems are based on a high availability
and operational reliability of the entire system. Additional advantages include:
●
Monitoring and diagnostic functions of the electronic drive system are
possible without any additional wiring
● The maximum available motor force is available immediately after pow‐
er-up
● No referencing required
● Easy commissioning
● Commutation settings are only required for initial commissioning
The use of an absolute encoder system enables that commuta‐
tion of the motor only needs to be carried out once upon initial
commissioning.
Incremental encoder If an incremental encoder system is used, the pole position has to be deter‐
mined every time the drive is switched on. This is done by means of a drive-
internal process every time the motor is switched on. Subsequently, the mo‐
tor power can develop.
The drive-internal procedure for commutation has to be carried
out every time the drive is switched on.
For more information on encoder systems, encoder signals and correspond‐
ing interface connections, please refer to the control units documentation
DOK-INDRV*-CSH********-PR□□-□□-P. For detailed information on the indi‐
vidual encoder types, please refer to the respective publications of the encod‐
er manufacturers.
If used in connection with the DIAX04 and ECODRIVE03 drives
by Rexroth, MBT motors may only be operated togerther with an
absolute measuring system. In this case, all current firmware ver‐
sions of DIAX04 and ECODRIVE03 can be used!
The combination of an incremental measuring system with MBT
motors cannot be used for DIAX04 and ECODRIVE03! These
kind of applications are not supported!
In connection with the new IndraDrive generation, MBT motors
can be combined both with incremental and with absolute meas‐
uring systems!
Suppliers for encoder systems include:
MBT High Synchronous Torque Motors 283/409
Application notes
R911298798_Edition 08 Bosch Rexroth AG