INVT Goodrive350 Series, Руководство по эксплуатации

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Communication extension card PROFIBUS communication card
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The PROFIBUS-DP system uses the services at the data link layer (Layer 2) through
service access points (SAPs). Functions of each SAP are clearly defined. For more
information about SAPs, see the related PROFIBUS master user manuals, that is,
PROFIdrive––PROFIBUS models or EN50170 standards (PROFIBUS protocol) for
variable-speed drives.
3. PROFIBUS-DP information frame data structure
The PROFIBUS-DP system allows fast data exchange between the master and VFD
devices. For VFD devices, data is always read and written in the master/slave mode.
VFDs always function as slave stations, and one address is clearly defined for each slave
station. PROFIBUS transmits 16-bit packets periodically. Figure 2-4 shows the structure
of the packet.
Parameter
identification (PKW)
Process data
(PZD)
Distributable zone
PKW1 PKW2 PKW3 PKW4
CW
SW
PZD2 PZD3
PZD2 PZD3
PZD12
PZD12
Fixed
zone
Figure 2-4 PROFIBUS-DP information frame data structure
Parameter zone:
PKW1––Parameter identification
PKW2––Array index number
PKW3––Parameter value 1
PKW4––Parameter value 2
Process data:
CW––Control word (transmitted from the master to a slave. For description, see Table 2-5)
SW––State word (transmitted from a slave to the master. For description, see Table 2-7.)
PZD––Process data (defined by users)
(When the process data is output by the master to a slave, it is a reference value; and when
the process data is input by a slave to the master, it is an actual value.)
PZD zone (process data zone): The PZD zone in a communication packet is designed for
controlling and monitoring a VFD. The master and slave stations always process the received
PZD with the highest priority. The processing of PZD takes priority over that of PKW, and the
master and slave stations always transmit the latest valid data on the interfaces.
CWs and SWs
Using CWs is the basic method of the fieldbus system to control VFDs. A CW is transmitted by