Siemens SINAMICS G120 - Page 163

Configuring the fieldbus
7.6 Communication via RS485
Inverter with CU230P-2 Control Units
Operating Instructions, 11/2013, FW V4.6.6, A5E02430659B AG
163
Additional settings
Parameters
Description
p0015 = 21
Drive device macro
Select the I/O configuration (USS fieldbus)
p0791[0 … 1]
Fieldbus analog outputs
Parameter to interconnect the analog outputs for control via the fieldbus
p2030 = 2
Fieldbus telegram selection
2: Modbus RTU
p2020
Baud rate
Factory setting: 19200 bit/s
p2024[0 … 2]
Modbus timing
(see Section "Baud rates and mapping tables (Page 164)")
•
p2024[0]: Maximum slave telegram processing time:
The time after which the slave must have sent a response to the master.
•
p2024[1]: Character delay time:
Character delay time: Maximum permissible delay time between the individual characters in the
Modbus frame (Modbus standard processing time for 1.5 bytes).
•
p2024[20]: Inter-telegram delay:
Maximum permissible delay time between Modbus telegrams (Modbus standard processing time for
3.5 bytes).
r2029
Fieldbus fault statistics
Displays receive faults on the fieldbus interface
p2040
Fieldbus monitoring time
0 ms … 1999999 ms, factory setting: 100 ms.
The more slaves that are connected in the network, the longer the fieldbus monitoring time must be.
If process data is not transferred within one cycle of the fieldbus monitoring time, then the inverter shuts
down with fault F01910.
p2040 = 0 ⇒ bus monitoring deactivated.