EEVblog Electronics Community Forum

Electronics => Beginners => Topic started by: Asgards on September 05, 2013, 05:30:11 pm

Title: Connecting to serial PLC over Ethernet network
Post by: Asgards on September 05, 2013, 05:30:11 pm
I have an older Mitsubishi PLC with a RS232 serial connector. I want to connect to this PLC over a local Ethernet network. I assume that I can use a serial to Ethernet converter for this, is that correct? If so, do you have any recommendations / experience how to setup such a connection?
Title: Re: Connecting to serial PLC over Ethernet network
Post by: SeanB on September 05, 2013, 06:25:13 pm
Funny, I got one at the local scrapyard recently, Lantronix unit.

(http://farm3.staticflickr.com/2869/9614282755_a052e39dea.jpg) (http://www.flickr.com/photos/33277124@N08/9614282755/)
IMG_1238 (http://www.flickr.com/photos/33277124@N08/9614282755/#) by SeanB_ZA (http://www.flickr.com/people/33277124@N08/), on Flickr

Title: Re: Connecting to serial PLC over Ethernet network
Post by: CalG on September 06, 2013, 12:49:58 am
Might ask here

http://www.plctalk.net/qanda/index.php (http://www.plctalk.net/qanda/index.php)
Title: Re: Connecting to serial PLC over Ethernet network
Post by: Asgards on September 07, 2013, 06:39:35 am
Thanks for the suggestions. To answer my own question, I did find a serial Ethernet converter here http://www.usconverters.com/index.php?main_page=product_info&cPath=66&products_id=225 (http://www.usconverters.com/index.php?main_page=product_info&cPath=66&products_id=225) which I was able to connect to the PLC. The setup is actually pretty easy once I found out how to use the converter.
Title: Re: Connecting to serial PLC over Ethernet network
Post by: peter.mitchell on September 07, 2013, 07:57:14 am
Funny, I got one at the local scrapyard recently, Lantronix unit.

(http://farm3.staticflickr.com/2869/9614282755_a052e39dea.jpg) (http://www.flickr.com/photos/33277124@N08/9614282755/)
IMG_1238 (http://www.flickr.com/photos/33277124@N08/9614282755/#) by SeanB_ZA (http://www.flickr.com/people/33277124@N08/), on Flickr

10/10 I've used a whole lot of these! Very reliable, often more so than what they are connected to, :P
Title: Re: Connecting to serial PLC over Ethernet network
Post by: SeanB on September 07, 2013, 01:18:53 pm
Want it?
Title: Re: Connecting to serial PLC over Ethernet network
Post by: AlfBaz on September 07, 2013, 03:26:21 pm
Hey Peter, you're from Oz. Have you tried those $170 jobs from jaycar? If you have are they any good?
Title: Re: Connecting to serial PLC over Ethernet network
Post by: peter.mitchell on September 08, 2013, 07:30:40 am
Hey Peter, you're from Oz. Have you tried those $170 jobs from jaycar? If you have are they any good?

I haven't tried that specific unit, no, however, I have tried a few cheap units, which all have long term stability issues, and considering the price, i'd just get a lantronix. We used them attached to between GSM modems and industrial equipment for remote management and monitoring with literally years of up-time and no issues. Here is one that is going pretty cheap if you want to pick one up http://www.ebay.com.au/itm/Lantronix-UDS-10-Device-Server-/121171423275?pt=AU_Servers&hash=item1c3661302b&_uhb=1 (http://www.ebay.com.au/itm/Lantronix-UDS-10-Device-Server-/121171423275?pt=AU_Servers&hash=item1c3661302b&_uhb=1) , probably been cable tied to some piece of ancient equipment sitting in a rack for the past 10 years.
Title: Re: Connecting to serial PLC over Ethernet network
Post by: AlfBaz on September 08, 2013, 07:38:09 am
I know could/should search but have you had any experience going the other way. More specifically Ethernet -> 485?

EDIT: PS thanks for that link, I'll keep an eye on it
Title: Re: Connecting to serial PLC over Ethernet network
Post by: Tooms on September 08, 2013, 07:40:18 am
Hi

I have before connected an home automatic controller there is having an serial port to the network and then having an virtual serial port on the pc

http://www.tooms.dk/articles_tutorials/ihc_serialportserver/default.asp (http://www.tooms.dk/articles_tutorials/ihc_serialportserver/default.asp)


Tooms

Title: Re: Connecting to serial PLC over Ethernet network
Post by: peter.mitchell on September 08, 2013, 07:48:31 am
I know could/should search but have you had any experience going the other way. More specifically Ethernet -> 485?

EDIT: PS thanks for that link, I'll keep an eye on it


I'm unsure what is meant by that? These devices are bi-directional so I'm not sure about "the other way". Also, they work fine for RS-485, though you have to be careful what you use them on, I find devices using RS-485 can be more susceptible to latency issues caused by the conversions and networks latency as opposed to devices using RS-232, which don't really give a shit.
Title: Re: Connecting to serial PLC over Ethernet network
Post by: bingo600 on September 08, 2013, 02:42:17 pm
Moxa also makes some neat Ether -> Serial units.
They have a "DLL" , that makes the Ether -> Serial ports come up as a "Com-Port" on Windows

/Bingo
Title: Re: Connecting to serial PLC over Ethernet network
Post by: madires on September 08, 2013, 03:15:31 pm
If you got an old router supported by openwrt you could use ser2net.