ABB ACS 800 Series, Firmware Manual

Page: 102 / 340

Program features
102
The Master position will be transferred at 6 ms intervals using data sets 41.1 and
41.2. Both data sets are required since the data set words are of integer type which
limits the position value to -32767 mm to 32767 mm. Hence, for a wider position,
range some of the unused bits in the Follower Control Word (signal
03.11 ) are
combined together and used as the multiplying factor for position value in terms of
32767. Six bits of the Follower Control Word are used for generating the multiplying
factor. With these six bits (one bit for sign), we can have a maximum possible range
of position value from -1048544 mm to 1048544 mm. The Follower Control Word
(signal
03.11 ) is modified to include the position multiplying bits, and a new Follower
Control Word (signal 03.37 ) is used for transmission from the Master to the Follower
drives in the Shaft synchro mode. The position remainder (signal 03.38 ) is
transferred using data set 41.2.
The Master transmits the new Follower Control Word (signal 03.37 ) which consists of
the new Follower Control Word and the position multiplying bits using data set 41.1
when the Synchro control is enabled with Par.
78.01 . When Synchro control is OFF
in the Master or Master is in EXT1, the Follower Control Word (signal 03.11 ) is
transmitted using data set 41.1. Similarly, when Synchro control is ON in the Master
and the drive is in EXT2, the Master position remainder value is sent using data set
41.2; when Synchro control is OFF or the drive is in EXT1, the Speed reference
(signal
02.02 ) is sent to the Follower.
The parameter 78.01 SYNCRO CONTROL activates the execution of the Shaft
synchro function in the Master and Follower drives. The position error is calculated in
all the Follower drives only when the Synchro control is ON. Therefore, the speed
correction according to the position error in the respective Follower drives does not
happen when Synchro control is OFF. Parameters
10.14 SYNC SEL and the signal
02.23 SYNC POS ERROR are not updated in the Follower drives if the Synchro
control is OFF. SYNC FAULT will not be generated if Synchro control is OFF.
However, actual position value
02.21 will be available even when the Synchro
control is OFF.
To configure the Shaft synchro function, do the following:
• enable the use of the function with parameter 10.14 SYNC SEL in both Master
and Follower drives. Define the basic data for speed correction in the Follower
drive.
• calculate the linear rope speed.
• define the basic data for speed reference calculation in the Follower drive.