92
Operating Instructions – MOVITRAC® B
5
Communication and unit profile
Startup
Actual value
description of PI
data
The parameters
Actual value description PI1 - PI3
define the content of the process
input data words transmitted by the frequency inverter to the higher-level controller (see
figure below). Each process data word is defined with an individual parameter. There-
fore, three parameters are necessary for describing the process input data.
The following parameters can be transmitted across the process data channel using
process input data words PI1 to PI3. 32-bit values, such as the actual position, are trans-
mitted in two process data words. You can decide yourself in which process data word
the more significant part (high) and the less significant part (low) is transmitted.
Scaling of process
data
The process data are always transmitted as fixed-point values to make for simple calcu-
lation in the ongoing system process. Parameters with identical units of measurement
5946342027
Assignment
Meaning
Scaling
NO FUNCTION
Assigning a process input data word with
NO FUNCTION
means
that the inverter system does not update this process input data
word. In this case, MOVITRAC
®
B returns the value 0000hex to
the higher-level controller.
SPEED
Set to
SPEED
, the frequency inverter returns the current actual
speed in rpm to the higher-level automation system.
The actual speed value can only be sent back properly if the
inverter can determine the actual motor speed via speed feed-
back. For applications with slip compensation, the deviation from
the real motor speed solely depends on the accuracy of the slip
compensation set by the user.
1 digit = 0.2 / min
OUTPUT CUR-
RENT
Set to
OUTPUT CURRENT
, the frequency inverter returns the
current actual value of the output current in [% In] to the higher-
level automation system (in percent, with reference to the nominal
current of the inverter).
1 digit = 0.1% I
N
ACTIVE CUR-
RENT
By assigning a process input word
ACTIVE CURRENT
, the fre-
quency inverter provides the actual active current value % I
n
to
the higher-level automation system.
1 digit = 0.1 % I
N
STATUS WORD 1
/
STATUS WORD 2
Assigning status word 1 or status word 2 to the process input data
allows for accessing status information as well as fault and refer-
ence messages.
SPEED [%]
Set to
SPEED [%]
, the frequency inverter returns the current
actual speed in % n
max
/ P302 to the higher-level automation sys-
tem.
4000
hex
= 100% n
max
IPOS PI-DATA
Set to
IPOS PI
(IPOS Process Input Data), an individual actual
value can be transmitted from the IPOS
plus®
program to the
higher-level controller via process input data. This setting allows
for exchanging up to 48 individually coded bits between the
IPOS
plus®
program and the higher-level controller using the pro-
cess data channel.
You can directly write process input data in IPOS
plus®
using the
command
SetSys PI
data. For more detailed information, refer to
the "IPOS
plus®
positioning and sequence control system" manual.
Three words with
individually
coded 16 bits
each can be
exchanged
between the
higher-level con-
troller and
IPOS
plus®
.
PI 1
PI 2
Process input data
PI 3
Status word 1
Status word 2
Act. speed val.
Apparent curr.
etc.
Status word 1
Status word 2
Act. speed val.
Apparent curr.
etc.
Status word 1
Act. speed val.
Apparent curr.
etc.
P876: ACT. VAL. DESCR. PI3
P875: ACT. VAL. DESCR. PI2
P875: ACT. VAL. DESCR. PI1
Status word 2
00
I
Summary of Contents for Movitrac B
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