Siemens SIMOTICS S-1FL6

Control functions
7.8 Communicating with the PLC
SINAMICS V90, SIMOTICS S-1FL6
Operating Instructions, 04/2019, A5E36037884-007
271
Modbus register
number
Description
Modbus
access
Unit
Scaling factor
Range or
On/Off text
Data/parameter
40960/40961 Number of pulses per
revolution
R/W - 1 0 to 16777215 p29011
40962/40963 Numerator of electronic
gear 0
R/W - 1 1 to 10000 p29012[0]
40964/40965 Numerator of electronic
gear 1
R/W - 1 1 to 10000 p29012[1]
40966/40967 Numerator of electronic
gear 2
R/W - 1 1 to 10000 p29012[2]
40968/40969 Numerator of electronic
gear 3
R/W - 1 1 to 10000 p29012[3]
40970/40971 Denominator of the
electronic gear
R/W - 1 1 to 10000 p29013
Parameter scaling
Due to the limits of the integer data in the Modbus protocol, it is necessary to convert the
drive parameters before transmitting them. This is done by scaling, so that a parameter,
which has a position after decimal point, is multiplied by a factor, to get rid of the fractional
part. The scaling factor is as defined in the above table.
7.8.2.2
Cyclic communication
Operating steps
Description
Comment
①
Configure the RS485 bus address by parameter
p29004.
You can configure the slave address from 1 to 31.
②
Select the communication protocol by parameter
p29007.
• p29007 = 0: No protocol
• p29007 = 1: USS protocol
• p29007 = 2: Modbus protocol
③
Select the command and setpoint source by parame-
ter p29008.
• p29008 = 1: Setpoint and control word from Modbus PZD
• p29008 = 2: No control word.
④
Set the transmission baud rate by parameter p29009.
• 5: 4800 baud
• 6: 9600 baud
• 7: 19200 baud
• 8: 38400 baud
• 9: 57600 baud
• 10: 76800 baud
• 11: 93750 baud
• 12: 115200 baud
• 13: 187500 baud