Table of Contents
Advertisement
MPH-02, MPB-02, MPD-02
Cyclic Data Transfer
DOK-INDRV*-MP*-02VRS**-FK01-EN-P
Sometimes it is possible to recognize a defective fiber optic cable by the
fact that hardly any light comes out at its end or that the optical fiber was
"drawn back" into the connector (check the face of the connector). Further
checks of the fiber optic cable cannot be carried out with simple means.
Defective fiber optic cables must be replaced.
To synchronize the drives in a ring, the master synchronization telegram
(MST) is sent at the beginning of every SERCOS cycle. The only
information the MST contains is the communication phase preset by the
master.
The content of master data telegram (MDT) and drive telegram
(AT = Antriebstelegramm) can be configured.
Once per SERCOS cycle time, a collective master data telegram for all
drives is sent from the control unit to the drives. The master data telegram
contains the master control word, the service channel and a configurable
data block. This data block mostly contains the command and limit values
the control unit wants to transmit to the drive to operate the corresponding
operating mode. The content of this data block can be configured by
means of the telegram settings.
The master data telegram is received by all drives in the ring at the same
time.
In addition, a separate drive telegram is sent once per SERCOS cycle
time from every drive to the control unit. The drive telegram contains the
drive status word, sections of the service channel and a configurable data
block. This data block mostly contains the actual and status values the
control unit needs from the drive to operate the corresponding operating
mode.
Master Control Word
The master control word is part of the master data telegram. The master
control word contains all important control information for the drives, such
as:
• drive on
• drive enable
• Drive Halt
• interpolator clock
• command operating mode
• real-time control bits 1 and 2
• control information for the service channel
Note:
The master control word is mapped to parameter S-0-0134.
The exact structure of this parameter is described in the
separate Parameter Description.
See Parameter Description "S-0-0134, Master control word"
The master control word is cyclically transmitted to the drive with every
master data telegram in the SERCOS clock (see S-0-0002, SERCOS
cycle time (TScyc)). For diagnostic purposes, the master status word
can be read via the S-0-0134, Master control word parameter.
Master Communication
4-37
Advertisement
Table of Contents
