FC101 Design Guide

7.1.4 Parameter Settings for Modbus
Communication
Parameter Function
Parameter 8-30 Prot
ocol
Select the application protocol to run for
the RS485 interface.
Parameter 8-31 Add
ress
Set the node address.
NOTICE!
The address range depends on the
protocol selected in
parameter 8-30 Protocol.
Parameter 8-32 Bau
d Rate
Set the baud rate.
NOTICE!
The default baud rate depends on the
protocol selected in
parameter 8-30 Protocol.
Parameter 8-33 Pari
ty / Stop Bits
Set the parity and number of stop bits.
NOTICE!
The default selection depends on the
protocol selected in
parameter 8-30 Protocol.
Parameter 8-35 Min
imum Response
Delay
Specify a minimum delay time between
receiving a request and transmitting a
response. This function is for overcoming
modem turnaround delays.
Parameter 8-36 Ma
ximum Response
Delay
Specify a maximum delay time between
transmitting a request and receiving a
response.
Parameter 8-37 Ma
ximum Inter-char
delay
If transmission is interrupted, specify a
maximum delay time between 2 received
bytes to ensure timeout.
NOTICE!
The default selection depends on the
protocol selected in
parameter 8-30 Protocol.
Table 7.2 Modbus Communication Parameter Settings
7.1.5 EMC Precautions
NOTICE!
Observe relevant national and local regulations
regarding protective ground connection. Failure to
ground the cables properly can result in communication
degradation and equipment damage. To avoid coupling
of high frequency noise between the cables, keep the
RS485 communication cable away from motor and brake
resistor cables. Normally, a distance of 200 mm (8 in) is
sucient. Maintain the greatest possible distance
between the cables, especially where cables run in
parallel over long distances. When crossing is
unavoidable, the RS485 cable must cross motor and
brake resistor cables at an angle of 90°.
195NA493.11
1
2
90°
1 Fieldbus cable
2 Minimum 200 mm (8 in) distance
Figure 7.3 Minimum Distance between Communication and
Power Cables
RS485 Installation and Set-... Design Guide
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