ABB RETA-01, User Manual

Page: 52 / 86

Communication
52
Modbus/TCP
Overview
This chapter describes the Modbus/TCP communication protocol
for RETA-01. For detailed information on Modbus/TCP
communication refer to Modbus/TCP protocol specification 1.0.
RETA-01 uses ABB Drives communication profile with
Modbus/TCP.
Register read and write
The drive parameter and data set information is mapped into a
4xxxx register area. This holding register area can be read from
an external device, and an external device can modify the register
values by writing to them.
There are no set-up parameters for mapping the data to the 4xxxx
register area. The mapping is pre-defined and corresponds
directly to the drive parameter grouping, which is being used by
the local drive control panel.
All parameters are available for reading. The parameter writes are
verified for correct value, and for valid register addresses. Some
parameters never allow writing (e.g. actual signals), some allow
writing only when the drive is stopped (e.g. set-up variables), and
some can be modified at any time.
Register mapping
The drive parameters are mapped to the 4xxxx area as follows:
In this mapping, the thousands and hundreds correspond to the
group number, while the tens and ones correspond to the
parameter number within a group. Register addresses 4GGPP are
shown in the table below. In the table, GG represents the group
number while PP is the parameter index within the group.
40001…40096 are reserved for data sets
40101…49999 are reserved for parameters.