MB40 & MB45 MODBUS TCP/IP Gateway
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Troubleshooting
A number of LED’s have been provided to assist with troubleshooting, should you run into problems
with the MB40.
Power Connected
Without any connections made except power, the Tx LED next to the D9 port should flash red once
roughly every 5 seconds. This confirms the gateway is on and operational.
Weather station Comms
If the Gateway is receiving messages from the weather station, the green Rx LED should flash in
response to the red Tx LED roughly every 10 seconds.
Ethernet
If a valid connection is made on Ethernet cable between another controller, network card, or Ethernet
switch, at least one LED on the Ethernet socket will be illuminated
– regardless of TCP/IP settings. If
not, there is a problem with the network equipment.
RS485
If any type of serial data is sent over RS485, the Rx LED will flash. If the serial data is a valid Modbus
command at the correct address, baudrate, and parity, the gateway will send a response. This will
cause the green Tx LED to flash.
Troubleshooting Procedure
1) Begin with the Gateway disconnected from all cabling and all DIP switches in the off position.
2) Apply 8 to 28 volts to the power terminals. Check the Tx LED next to the D9 port. It should flash
red roughly once every 5 seconds. If so, move to step 3. If not:
a) Check the wires of the power supply are the correct way around.
b) Probe the power terminals with a multimeter to ensure you are receiving the required DC
voltage.
3) Plug the weather station into the MB40 using the D9 connector. Check the Rx LED next to the D9
connector. It should now flash green in combination with the red LED. If so, move to step 4. If not:
a) Check that the weather station is powered.
b) Check the cabling from the weather station to the gateway.
c) Plug an Ethernet cable from the gateway to a controller (either directly or via an Ethernet
switch). After a moment, the lights on the Ethernet socket should illuminate/flash. If so, go to
step 4. If not, there is a problem with the network hardware. Try:
i)
Making a direct connection between the MB40 and a PC.
4) Use the switches to set the TCP/IP settings. Using a machine in the same subnet, browse to the
IP address of the gateway. If you see the MB40 webpage, you have successful Ethernet
communications. The gateway can be polled by a Modbus TCP/IP master on this address. If not:
a) Check your network settings to make sure the gateway is in the same subnet as your other
network hardware. On windows:
i)
Press: w R to open the run dialogue box.
