ABB ACH550-UH HVAC, Руководство пользователя

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1-262 ACH550-UH User’s Manual
Fieldbus adapter
Details for the ABB Drives profile (which apply for all protocols) are provided in ABB
drives profile technical data on page 1-271 .
Control interface
In general, the basic control interface between the fieldbus system and the drive
consists of:
• Output Words:
–
CONTROL WORD
–
REFERENCE
(speed or frequency)
– Others: The drive supports a maximum of 15 output words. Protocols limits
may further restrict the total.
• Input Words:
–
STATUS WORD
– Actual Value (speed or frequency)
– Others: The drive supports a maximum of 15 input words. Protocols limits may
further restrict the total.
Note: The words “output” and “input” are used as seen from the fieldbus controller
point of view. For example an output describes data flow from the fieldbus controller
to the drive and appears as an input from the drive point of view.
The meanings of the controller interface words are not restricted by the ACH550.
However, the profile used may set particular meanings.
Control Word
The
CONTROL WORD
is the principal means for controlling the drive from a fieldbus
system. The fieldbus controller sends the
CONTROL WORD
to the drive. The drive
switches between states according to the bit-coded instructions in the
CONTROL
WORD
. Using the
CONTROL WORD
requires that:
• The drive is in remote (REM) control.
Fieldbus
Fieldbus Controller
Control Word (CW)
References
Status Word (SW)
Actual Values
Parameter R/W Requests/Responses
Process I/O
Service
Messages
(Acyclic)
(cyclic)