Hi all,

I have a solar package in the field. In it there is a serial to ethernet converter (terminal server). The serial port on this terminal server is used to gather data from a totalflow using totalflow protocol as a terminal server modem.

The Morningstar controller in the solar package has a device called a Meterbus adapter that can be polled via MODBUS ascii/rtu or MODBUS TCP. I am trying to find a device with 2 serial ports that can speak both modbus tcp and be a terminal server. Other option is to add a modbus ascii to ethernet adapter, and a small ethernet switch. I am limited to how much more power I can draw. I have approx 3 watts to play with.

 

David,

If you already have a terminal server (aka device server) installed, and the Meterbus adapter talks Modbus/TCP (Ethernet), it seems that all you need is a small unmanaged switch. The smallest models are usually 5-ports, and power consumption is generally under 3W. Also, industrial models are very economical, usually under 100 $US.

Regards,

Paul Wacker
Product Manager (ICOM)
Advantech Corp.

 

I haven't bought one of these myself, but it seems to meet your criteria:

http://www.advantech.com/products/EKI-1222/mod_GF-TUBW.aspx

Advantech EKI-1222 2-port Modbus Gateway. Power consumption is 2.5 watts.

You can probably find equivalents from several other companies if you do a search with Google.