Operating instructions

Functions
5.11 Operation in fieldbus systems
CU240S and CU240E Control Units, FW 3.2
194 Operating Instructions, 03/2009, A5E02440075B AA
Once the read request has been issued and a waiting time of one second has elapsed, the
parameter values are copied from the inverter via SFC 59 and saved in DB2.
FC3 to write parameters to the inverter
Figure 5-41 Function block for writing parameters
You first have to define which value (MW35) is written to which parameter index (MW23) of
which parameter (MW21). The specifications are saved in DB3.
SFC 58 copies the specifications for the parameters to be written from DB3 and sends them
to the inverter. No other write requests are permitted while this one is being processed.
For more information about SFC 58 and SFC 59, consult the STEP 7 online help.