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612 Fieldbus control through the embedded fieldbus interface (EFB)
Control of drive outputs through EFB
The address selection parameters of the data input/outputs have a setting with
which the data can be written into a storage parameter in the drive. These storage
parameters are readily selectable as signal sources of the drive outputs.
The desired values of the relay outputs (RO) and digital input/outputs (DIO) can
be written in a 16-bit word into
as the source of those outputs. Each of the analog outputs (AO) of the drive have
a dedicated storage parameter
which are available in the source selection parameters
AO2
source.
￭
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.
Modern Modbus master devices typically provide a means to access the full range
of 65536 Modbus holding registers. One of these methods is to use 6-digit decimal
addresses from 400001 to 465536. This manual uses 6-digit decimal addressing
to represent Modbus holding register addresses.
Modbus master devices that are limited to the 5-digit decimal addressing may
still access registers 400001 to 409999 by using 5-digit decimal addresses 40001
to 49999. Registers 410000 to 465536 are inaccessible to these masters.
Note: Register addresses of 32-bit parameters cannot be accessed by using 5-digit
register numbers.
About the control profiles
A control profile defines the rules for data transfer between the drive and the
fieldbus master, for example:
•
if packed boolean words are converted and how
•
how drive register addresses are mapped for the fieldbus master.
You can configure the drive to receive and send messages according to the ABB
Drives profile or the Transparent profile. With the ABB Drives profile, the embedded
fieldbus interface of the drive converts the control word and status word to and
from the native data used in the drive. The Transparent profile involves no data
conversion. The figure below illustrates the effect of the profile selection.
10.99 RO/DIO control
(13.91 AO1 data storage
word, which is then selected
and
13.92 AO2 data
13.12 AO1 source
storage),
and
13.22
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