ABB ACQ80, Руководство по прошивке

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348 Fieldbus control through the embedded fieldbus interface (EFB)
emergency stop, selection between external control locations 1/2, or fault
reset). The drive switches between its states according to the bit-coded
instructions of the CW.
The fieldbus CW is either written to the drive as it is or the data is converted.
See section
About the control profiles
(page
350
).
The fieldbus Status Word (SW) is a 16-bit or 32-bit packed boolean word. It
contains status information from the drive to the fieldbus controller. The drive
SW is either written to the fieldbus SW as it is or the data is converted. See
section
About the control profiles
(page
350
).
 References
The references are provided by MPPT and does not depend on any user settings.
For more information on MPPT, see chapter
Flow calculation
on page
45
.

Actual values
Fieldbus actual signals (ACT1 and ACT2) are 16-bit or 32-bit signed integers.
They convey selected drive parameter values from the drive to the master.
Whether the actual values are scaled or not depends on the settings of
58.28
EFB act1 type
and
58.29 EFB act2 type
. See section
About the control profiles
(page
350
).
 Data input/outputs
Data input/outputs are 16-bit or 32-bit words containing selected drive
parameter values. Parameters
58.101 Data I/O 1
…
58.114 Data I/O 14
define the
addresses from which the master either reads data (input) or to which it writes
data (output).
 Register addressing
The address field of Modbus requests for accessing holding registers is 16 bits.
This allows the Modbus protocol to support addressing of 65536 holding
registers.
Historically, Modbus master devices used 5-digit decimal addresses from 40001
to 49999 to represent holding register addresses. The 5-digit decimal
addressing limited to 9999 the number of holding registers that could be
addressed.