Module Reserved Channel Concept; Rtd Range Information - ABB Remote I/O RIO600 Installation And Commissioning Manual

1MRS757488 H
7.1.27
7.1.28
RIO600
Installation and Commissioning Manual
the binary input readable points, that is points mentioned in the point list, of the
SIM8F/SIM4F module and the SCM module of 4I4O application type.
• If the binary input read method is set to "Latched", the RIO600 Modbus slave
responds with the first status change value between the polls for a Modbus poll
that requests the status of binary input channels of the DIM8 H or DIM8 L module
and the binary input readable points of the SIM8F/SIM4F module and the SCM
module of 4I4O application type. For example, if the value for a particular binary
input changes from status "0" to status "1" between two consecutive Modbus
polls and then back to status "0", the RIO600 Modbus shows value "1" to the
Modbus master. The value here is latched to the first status change between the
polls.
• If the binary output write is set to "Not Allowed" and the Modbus master tries to
write a value to either DOM channels, SIM8F/SIM4F's or SCM's writeable
channels, this results in exception code 4.
• If the analog output write is set to "Not Allowed" and the Modbus master tries to
write a value to either AOM channels, this results in exception code 4.
• If the time synch source is not selected as "Modbus" and the Modbus master tries
to write a value to the time registers, an exception code 4 is sent from the RIO600
Modbus slave to the Modbus master.

Module reserved channel concept

Keeping the future expansion in consideration, RIO600 Modbus implementation
reserves a few channel numbers.

RTD range information

RIO600 Modbus implementation can be used to retrieve the range information for
each of the RTD channels. Modbus address 704 onwards can be used in a 3X/4X read
poll to retrieve the range information of any RTD channel present in the stack.
123 shows the manner in which the RTD range information for RTD channels should
be interpreted.
Table 123: Reporting of RTD range information
Range
normal
high
low
high high
low low
In case a channel is reserved for future use, value "0" should be
reported for it.
Modbus TCP communication
Value reported
0
1
2
3
4
Section 7
Table
181