3.3
Process Data Description
The process data description defines the content of the process data to be transmitted. All three
process data words can be assigned individually by the user. In general, the process input data and
the process output data are handled separately. This enables you to specify which process output
data (setpoints) are to be transmitted to the inverter from the control unit, and which process input
data (actual values) are to be transferred from the MOVITRAC
®
31.. inverter in the opposite direction
to the higher-level control unit for your particular application. The following six fieldbus parameters
are available for defining the individual process data:
P560
PO1 Setpoint Description
P561
PI1 Actual Value Description
P562
PO2 Setpoint Description
P563
PI2 Actual Value Description
P564
PO3 Setpoint Description
P565
PI3 Actual Value Description
When one of the above-mentioned parameters is changed, acceptance of the process output data for
setpoint processing via the fieldbus is automatically blocked. The process output data received will
not be processed according to the new actual value and setpoint descriptions until the fieldbus
parameter
P570
Enable Fieldbus Setpoints = YES
is re-activated (see also Section 3.3.4.).
3.3.1
Setpoint Description for the PO Data
The
PO1 - PO3 Setpoint Description parameters define the content of the process output data words,
which are sent via the fieldbus system from the higher-level automation unit (Fig. 6). Each process
output data word is defined by its own parameter, so altogether three fieldbus parameters offering
the same options are available to describe the process output data.
M
O
VI
TRAC
®
841
E
Q
RUN
BUS
FAULT
PD1
PD2
PD3
PD1
PD2
PD3
AW 44
AW 42
AW 40
EW 44
EW 42
EW 40
PD3
PD2
PD1
PD3
PD2
PD1
Fieldbus
CONTROL MODE
Process input data (PI)
Process output data (PO)
PLC address area
00315AEN
Fig. 5: Process data mapping in the PLC
Inverter Control
with Process Data
3
12
MOVITRAC
®
31.. Fieldbus Unit Profile
Phone: 800.894.0412 - Fax: 888.723.4773 - Web: www.clrwtr.com - Email: [email protected]
