Chapter 6 – Communication
NMBA-01 Installation and Start-up Guide
6-5
Multiple Drive Control
Set-up
Multiple Drive Control needs only parametrisation of one single drive,
the first drive in the ring. To configure the Modbus adapter, the fieldbus
parameters of the first drive are set by means of its control panel. (See
Chapter 5 for more specific information.) The drive in question is at that
time connected point-to-point with the NMBA-01(see
Figure 4-2). After
the Modbus adapter has been configured, the drives can be
reconnected for Multiple Drive Control.
During initialisation of the NMBA-01, the number of drives connected to
the ring is checked. The slaves are autonumbered starting from the first
drive in the ring. For example if fieldbus parameter
03 STATION
NUMBER of the first drive is 5, then the station number of the second
drive is 6 etc. In Multiple Drive Control, the NMBA-01 sends only two
fieldbus parameters to all other drives in the ring. These parameters
are
01 MODULE TYPE and 03 STATION NUMBER and they are read
only.
Parameter Handling
The NMBA-01 can read and write up to 99 parameters in one frame if
these are in the same parameter group. The user can read and write
(Modbus function codes 0x03, 0x06 and 0x10 Hex) all parameters of
each drive in Multiple Drive Control as if they were each connected to
their own NMBA-01 module. However, the response time might be
longer depending on the number of parameters to be handled.
Broadcast messages cannot be used for changing parameters.
Data Set
Communication
Data sets 1, 3, 5,... (data from NMBA-01 to the drive) can be used in
broadcast messages. However, data sets 2, 4, 6,... (data from the drive
to the NMBA-01) cannot be used in broadcast messages.
efesotomasyon.com - Control Techniques,emerson,saftronics -ac drive-servo motor
