MB40 & MB45 MODBUS TCP/IP Gateway
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Modbus TCP/IP & Ethernet Webserver
To communicate over a TCP/IP network, the MB40 needs five pieces of information:
1.
The Internet Protocol (IP) address of the MB40 within the network. Set by the user
2.
The Subnet Mask of the network. Set by the user
3.
The Default Gateway of the network. Set by the user.
4.
A unique MAC address. Shipped preloaded by Environdata.
5.
The TCP/IP port the request is being sent on. For the MB40, Modbus TCP/IP is on port 502,
and the webserver (HTTP) is on port 80.
These settings themselves can be set by one of three available methods:
1.
The 8 DIP switches next to the D9 connector.
2.
Modbus registers (using either Modbus RTU on RS485 or Modbus TCP/IP on Ethernet)
3.
The webpage.
Configuration Using Switches –Switch 1
Switch one determines where the TCP/IP settings are loaded from when power is applied to the
MB40. With this switch off, settings are loaded from the current values of the switches, regardless of
previous settings. With the switch on, the settings are loaded from internal memory - saved after
being previously configured via the webpage or Modbus.
Table 6: TCP/IP mode switch
Power Up Configuration
Switch 1
OFF
TCP/IP settings from switches
ON
TCP/IP settings from internal persistent memory
Configuration Using Switches –Switch 2
Switch two is the “panic switch”, returning the MB40 to default if the user writes incorrect values or
doesn’t otherwise know what settings the card currently possesses. To use, flick the switch on, hold
for one second, and turn back off again.
Don’t leave this switch on; the card will be constantly
resetting and therefore unresponsive.
Default Values
IP Address: 192.168.1.100
Subnet Mask: 255.255.255.0
Default Gateway: 192.168.1.1
Table 7: TCP/IP Reset Switch
Reset to Default
Switch 2
OFF
No action
ON
TCP/IP settings reset to default
