Connection To Modbus - HMS Networks Intesis IN700-485 Series User Manual

Connection to Modbus

11.3. Connection to Modbus
• Ethernet port for Modbus TCP and Console connection
Connect the communication cable from the Modbus TCP network to the Ethernet port of the gateway.
IMPORTANT
Use a straight Ethernet UTP/FTP CAT5 or higher cable.
IMPORTANT
If communicating through the LAN of the building, contact the network administrator and make
sure traffic on the used port is allowed through all LAN paths.
NOTE
After powering up the Intesis gateway for the first time, DHCP will be enabled for 30 seconds.
After that time, if a DHCP server provides no IP, the default IP 192.168.100.246 will be set.
• Port B EIA-485 connection for Modbus RTU
Connect the EIA-485 bus to connectors B1 (B-), B2 (A+), and B3 (SNGD) of the gateway's Port B.
IMPORTANT
Respect the polarity.
IMPORTANT
Remember the characteristics of the standard EIA-485 bus:
– Maximum distance of 1200 meters.
– Maximum of 32 devices connected to the bus.
– A termination resistor of 120 Ω is needed at each end of the bus. The gateway has an internal
bus biasing circuit already incorporating the termination resistor. It can be enabled using the
DIP switches:
• Position 1
ON: 120 Ω termination active
OFF: 120 Ω termination inactive
• Position 2-3
ON: Polarization active
OFF: Polarization inactive
– If the termination resistor is enabled and you install the gateway at one of the ends of the bus,
do not install an additional termination resistor at that end.
NOTE
Only for the Modbus client to BACnet server application, you can also use Port A for the Modbus
RTU connection (see
• Port B EIA-232
Connect the serial cable EIA-232 from the external serial device to the EIA-232 connector of the gateway Port
B.
NOTE
This is a DB9 male (DTE) connector that only uses the TX, RX, and GND.
IMPORTANT
Respect the maximum distance of 15 meters.
USER MANUAL Version 1.0
Figure 4 (page 22)).
IN700-485 Series
Page 25 of 36