1-240 ACH550-UH User’s Manual
Embedded fieldbus
Mapping summary
The following table summarizes the mapping between the ACH550 (parameters and
I/0) and Modbus reference space. For details, see Modbus addressing below.
Communication profiles
When communicating by Modbus, the ACH550 supports multiple profiles for control
and status information. Parameter 5305 (
EFB CTRL PROFILE) selects the profile used.
•
ABB DRV LIM – The primary (and default) profile is the ABB DRV LIM profile, which
standardizes the control interface with ACH400 and ACH550 drives. This profile
is based on the PROFIBUS interface, and is discussed in detail in the following
sections.
•
DCU PROFILE – Another profile is called the DCU PROFILE profile. It extends the
control and status interface to 32 bits, and is the internal interface between the
main drive application and the embedded fieldbus environment.
•
ABB DRV FULL – This profile standardizes the control interface with ACS600 and
ACS800 drives. This profile is also based on the PROFIBUS interface, and
supports two control word bits not supported by the
ABB DRV LIM profile.
Modbus addressing
With Modbus, each function code implies access to a specific Modbus reference set.
Thus, the leading digit is not included in the address field of a Modbus message.
Note: The ACH550 supports the zero-based addressing of the Modbus
specification. Holding register 40002 is addressed as 0001 in a Modbus message.
Similarly, coil 33 is addressed as 0032 in a Modbus message.
Refer again to the “Mapping Summary” above. The following sections describe, in
detail, the mapping to each Modbus reference set.
0xxxx Mapping – Modbus Coils. The drive maps the following information to the
0xxxx Modbus set called Modbus Coils:
• Bit-wise map of the
CONTROL WORD (selected using parameter 5305 EFB CTRL
PROFILE). The first 32 coils are reserved for this purpose.
• Relay output states, numbered sequentially beginning with coil 00033.
ACH550 Modbus Reference Supported Function Codes
• Control Bits
• Relay Outputs
Coils(0xxxx) • 01 – Read Coil Status
• 05 – Force Single Coil
• 15 – Force Multiple Coils
•Status Bits
• Discrete Inputs
Discrete Inputs(1xxxx) • 02 – Read Input Status
• Analog Inputs Input Registers(3xxxxx) • 04 – Read Input Registers
• Parameters
• Control/Status Words
• References
Holding Registers(4xxxx) • 03 – Read 4X Registers
• 06 – Preset Single 4X Register
• 16 – Preset Multiple 4X Registers
• 23 – Read/Write 4X Registers
To Next Page
Loading...
