Siemens SINAMICS V90 Operating Instructions Manual page 188

Control functions
7.7 Communicating with the PLC
8.
9.
Example 2
This example shows the operating procedures when we use the setpoint and control word
from Modbus as the Modbus control source in IPos control mode.
1.
2.
3.
4.
5.
188
Write the control word you desired via the register 40100.
Note:
Bit 10 of the register 40100 must be set to 1 to allow the PLC to control the drive.
You need to trigger a rise edge for OFF1 to enable SON status for the motor, and
OFF2 and OFF3 must be set to 1. The step must be executed when you enable SON
for the first time.
For example, we write 0x41E to the register 40100 firstly and then write 0x41F to the
register. The motor now is in SON status. You can check the control word definition
table below to see the meaning of "0x41E" and "0x41F".
Write the speed setpoint via the register 40101.
Note:
You can calculate the actual speed value with the scale factor. Value 0x4000 repre-
sents the value of 100% × motor rated speed. Therefore, 0x2000 represents half of
the motor rated speed.
Set RS485 bus address for the drive.
• p29004 = 1
Select the Modbus protocol by p29007.
• p29007 = 2
Select Modbus control source by p29008.
• p29008 = 1
Set the transmission baud rate by p29009.
• p29009 = 8 (38400 baud)
Save the parameters and restart the drive.
SINAMICS V90, SIMOTICS S-1FL6
Operating Instructions, 07/2015, 6SL3298-0AV60-0BP0