DH485 to ethernet bridge

Hi, I have PanelViev 1000 grayscale and SLC5/03. I run SCADA via ethernet bridge that is connected to SLC5/03 via RS232. The PanelView is connected with PLC via DH485. I run out of ports to connect another ethernet bridge to PLC so I can modify PLC online, but on HMI there is one DH485 (RJ45) port that I use to connect PC via 1747-UIC. Due to the need of some changes every now and then I would like to use PanelView DH485 (R45) port to connect it to the ethernet bridge so I can access PLC and HMI from control room.
I was thinking about 1747-UIC usb to DB9 conversion and connect it with the ethernet bridge, but I am not sure will it work.
So my question is: Is there any way of connecting DH485 (RJ45) to the network so I can access it via ethernet bridge software virtual port or any other way?

Thanks for help

Prosoft has had a couple offerings that should be able to do it. Look for the discontinued 5201-DFNT-DH485 or current A-DH485R/B.

Disclaimer: I've never used either

Thanks for this, I have already looked at it, but the cost is to big. Any other solutions?

Maybe a long shot but.... how about changing the 5/03 to a 5/05, then configure the 5/05 DB9 for DH485 and using the DB9 for the panelview but you have Ethernet for the rest

Still not a cheap option either but maybe you can find a used 5/05? or if you have a spare slot adding a 1747-AENTR?

Or a 3rd option... change out both the HMI and PLC if the machine is going to be around for sometime

Part 1: No Cheap Way

Welcome to the PLCTalk forum community, and thank you for all the excellent detail in your post.

Unfortunately, there is no EtherNet/IP to DH485 gateway that is inexpensive and easy to connect to your system. There are expensive ones (EquusTek and Prosoft) and they will require some extra wiring devices.

You would connect the EtherNet/IP to DH485 gateway to a DH485 trunkline with three 1747-AIC isolators: one for the gateway, one for the SLC-5/03 DH458 jack, and one for the PanelView's DH485 Communication Port.


You probably have a 2711-K10G3 or -T10G3. These have the classic 2-plug DH485 network port and an RS-232 port that only supports line printers (it can't be used for upload/download).

The DH485 port works like you have described: the "DH485 Communication Port" is the flatter "AMP" connector that connects to the RJ-45 style connector on an SLC-5/01, 02, or 03 controller.

The "DH485 Programming Connector" is the RH-45 connector and allows you to connect a computer with PanelBuilder32 software via a 1747-PIC or 1747-UIC for upload/download purposes.

You asked if there might be a way to use the RS-232 port that's on the 1747-UIC to access the PanelView from Ethernet using an Ethernet/Serial converter.

There is not: that RS-232 port on the 1747-UIC has the same functionality (DH485 protocol only) as the RJ-45 port on the 1747-UIC, just with a different voltage and signal type.

Part 2: No Easy Way

An interesting part of your post was:

> I run out of ports to connect another ethernet bridge to PLC so I can modify PLC online

Click to expand...

That tells me that you don't have a "protocol aware" device like a 1761-NET-ENI that knows about EtherNet/IP and DF1 protocols. Instead, you have a virtual serial port server, which are simple and generic and inexpensive. You can only connect one PC, because it uses a TCP/IP socket to transport serial data to that RS-232 port as a "virtual serial port".

Can you post exactly what make and model you have ?

The SLC-5/03 controller actually does support DF1 Full Duplex to DH485 protocol "pass through" that allows you to access devices on the DH485 network from a connection to the RS-232 port.

Because you are using a virtual serial port, you can configure RSLinx Classic for the "KF3/KE" mode, not "DF1 Point to Point" mode, and enable passthrough in the status files of the SLC-5/03, and you could browse the DH485 network and see both the SLC-5/03 and the PanelView 1000.

BUT.... you will find that passthrough has a limit on the size of messages that it can handle, and for that reason you can't use it to download/upload *.PVA application files to a PanelView Standard terminal.

Darnit.

Part 3: A Parallel Path for Serial Connections

You said that your goal is to be able to access both the SLC-5/03 and the PanelView 1000 from a comfortable and safe location in a control room, over the Ethernet network.

You're already accessing the SLC-5/03 using a "virtual serial port".

So... what about a "virtual USB port" ?

The USB chipset inside the 1747-UIC isn't anything special, and it is running the very tolerant DF1 Full Duplex protocol over USB, the same as an old fashioned 1770-KF3 or 1747-KE would run over RS-232.

So it's entirely possible you could use a device that has both Ethernet and a USB port as a "virtual USB port" with USB redirection software, very similar to how you're running a virtual COM port now.

There's a commercial product called FlexiHub that I have a subscription for to service machines we have deployed around the world. It allows me to connect a USB port with an activation dongle (a very expensive software license) in my office to an HMI computer at the customer site via the Internet and a VPN (we use TeamViewer). It has been very stable and successful and has saved me thousands of dollars and weeks of travel time.

I tend to agree with the guys at FlexiHub: you can do this with a smooth commercial product, or take the bumpier road of open source.

https://www.flexihub.com/usb-over-ip-raspberry-pi/

https://www.virtualhere.com/usb_server_software

Anyone on the Forum got a PanelView and a Raspberry Pi and some free time ?

Hi All,
Thanks for all the ideas, at first swapping SLC05/03 to SLC05/05 is not possible due to limited budget and work involved in this solution, but thanks for idea.
I like the idea of USB over ethernet, or virtual USB. Over the weekend I have looked for other solutions and I have found "WAVLINK Print Server, 10 / 100Mbps Ethernet to USB 2.0 Network LPR Print Server for Windows", this allow also other devices to be shared via ethernet so I'll give a try.

Regarding connection setup for SCADA I use USR-TCP232-306 bridge to connect to DB9 on SLC05/03. On control PC I have installed USR-COM software that create virtual COM to which I connect via IWS. It works superb, it is very stable and reliable. On power down it reconnects automatically. I use other bridge HF2211 for RS485 connectivity with energy monitor, this bridge don't require software and allows for converting RTU to RTU over TCP/IP, as well works great. Both solutions are less than £100, together.
I will give a try with this USB over ethernet and let you know, somebody may look for similar solution in the future.

Most Ethernet print servers are typically very limited in their functionality. If the only evidence that it supports memory devices and HID devices is a graphic showing icons of a camera and a mouse, I don't recommend buying one expect it to provide a virtual USB redirect utility suitable to run a COM port driver.

I would look instead for something labeled a "Ethernet USB Server".

This thread got me interested in whether a networked USB serial server would work with the 1747-UIC driver in RSLinx Classic.

I spent a little time experimenting with the VirtualHere software, which has a generous trial period and inexpensive ($50 USD) license. It runs on a tiny footprint on a Raspberry Pi 3 B (not the B+, interestingly), and I happen to have a box full of them retired from another project.

The initial configuration was easy and straightforward, but making sure that the Windows USB drivers were properly installed and configured required some reboots and retries. I got it working both in a Windows 10 Professional 64-bit computer, and in a Windows 7 32-bit VMWare Virtual machine.

The 1747-UIC was the aftermarket alternative unit from PLCCables, not a genuine A-B device.

This isn't a true "EtherNet/IP to DH485 bridge". Instead, it allows an engineering workstation in a system like the one described in this thread to connect to an old PanelView or SLC-500 system on DH485 over a TCP/IP network as though they were sitting a meter from the system using a USB connection and the 1747-UIC.

I am after first tests, and so far it looks great. I have tested it on Windows 7 and USB network server works with 1747-UIC, I have tested Download, Upload, Online so now I will run it over longer period of time to see if it is stable enough to be reliable for my application.
The device I used is Wavelink WL-NU78M41.
It require software which create Com port, but in my case I had to set specific Com because as default it assign already used Com so there was port conflict.
There is small web page for this USB network server where network parameters can be set. Simple enough to setup and use.
Thanks all for ideas and effort.

Thanks very much for that update, especially the specific hardware.

I am pleasantly surprised to learn that such an inexpensive device that's largely advertised for printer redirection works well as a serial COM port redirector, even having an easy-to-use COM port configuration on its configuration webpage.