Host Engineering Forum

General Category => ECOMs and ECOM100s => Topic started by: Henryp on December 10, 2014, 07:27:56 PM

Title: Ecom 100 Modbus port to SCADA communications
Post by: Henryp on December 10, 2014, 07:27:56 PM

Can an Ecom 100 be set to a Modbus port other than 502 like the Do-more internal port can be?

Title: Re: Ecom 100 Modbus port to SCADA communications
Post by: Greg on December 15, 2014, 03:58:11 PM

Yes. Use NetEdit's Peer-to-peer settings. In the Add Device Address dialog you can change the port number to whatever you want.

Title: Re: Ecom 100 Modbus port to SCADA communications
Post by: Henryp on February 02, 2015, 06:38:00 PM

Changing the port number in the peer to peer settings didn't work The PLC still answered to SCADA Modbus commands on port 502. Attach is a screen print.

Title: Re: Ecom 100 Modbus port to SCADA communications
Post by: Controls Guy on February 02, 2015, 08:17:48 PM

I believe it will always respond on 502, even when you specify a different port.  So "change" might not be the correct word, as opposed to maybe "add" the other port.  IIRC, the Modbus protocol spec recommends or requires that behavior.  Did you try polling on the new port you specified?

Title: Re: Ecom 100 Modbus port to SCADA communications
Post by: Greg on February 03, 2015, 08:26:18 AM

Sorry Henryp, I assumed you wanted the ECOM100 to be the Modbus TCP Client (Master). That is what you use the peer-to-peer table for; to configure the ECOM100 as the client (master). If, however, you want the ECOM100 to be the Modbus TCP Server (Slave), then, no, it is not possible to have it answer on any other TCP port other than 502 for Modbus TCP comms.

Title: Re: Ecom 100 Modbus port to SCADA communications
Post by: Controls Guy on February 03, 2015, 10:29:49 AM

Oh OK, maybe what I was saying applies to Do-More instead.

Title: Re: Ecom 100 Modbus port to SCADA communications
Post by: Henryp on February 03, 2015, 11:30:00 AM

Could this feature be added in the future to the Ecom 100?  The internal Do-More port can already do this.  From a security stand point it is a best practice not to use and block the standard 502 port if possible.