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Remote programming 1

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itsmoked

Electrical
Feb 18, 2005
19,114
I'm building a control panel that will have a typical HMI touch panel screen and small PLC. Usually my customers are within an hour of me so the inevitable, "I forgot to tell you about this", is not a BIG problem and I can show up and 'support' my customer fairly conveniently.

This time though the customer will be more remote. About 3 hrs one way. Not impossible but not great. (Good as a test subject - see below)

I'll be using a PLC that is programmed via RS232 and the HMI is USB programmed. IF I need to tweak something for the customer it would certainly be a superior solution if I could have them plug an Ethernet cable into a port somewhere giving me access to the two panel control units.

So! Does anyone have suggestions for a single board computer that might be capable of this? I'd just build it into the panel from the start. Perhaps a PC104 or that company that used to make SBCs that screwed on top of 5-1/4" drives (Asomething??) Maybe some small web server board?

Any other suggestions for slaying this beast are welcome.

Keith Cress
kcress -
 
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I'm not sure if the following is your planned approach... Get the "command and control" up and running on the new local embedded SBC (using temporary local monitor, mouse, keyboard). Once that's up and running, then Windows Remote Desktop or Linux equivalent makes it remotely-controllable with not much addition effort.

So you're looking for a small reliable SBC running an OS that offers easy remoting?

Does the system already provide hooks to support this?

If the whole system is simple, I wonder if old fashioned dial-up access into your system might be easier.
 
I know that anything PC-based with Ethernet could work in this situation. It's been so long that I can't even remember what we did exactly, but we had a WinNT SBC with an RPC client on Long Island, and another with an RPC server in Anaheim, and we were able to directly talk through the internet. Unfortunately, that was about 16 yrs ago, and all I remember was that we used Turbo Pascal, but I don't have access to any of the source code at this moment, since I'm in Mammoth.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize
 
Suffering in Mammoth with all that snow and whirring ski lifts.. That's rough!


VE1BLL; Yes that's it. Both the HMI and the PLC I have to download into come with "free" downloadable SW interfaces that connect to the hardware.

IR; That's a good idea. I can use VMware (a program) that lets me see and run a remote computer over the web. Maybe I could use a cheap netbook computer and just load both the apps into it and load it with VMware for the next best thing to being there.

I remembered that SBC name -> Ampro. Ack! Never mind they've gone all useless with distributors and a website that blows.

Keith Cress
kcress -
 
The SBC solutions are a lot easier to implement these days.

We are using an Advantech AIMB-270 with an I5/I7 core for some significant number crunching; this model might be a bit overkill for your application but I recommend Advantech.

Z
 
Sadly, snow is dreadfully lacking. I'd guess about 40% of the runs are closed due to insufficient coverage. The base is barely the advertised 2 ft. Dirt is certainly popping up, here and there.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize
 
Nice board there VE1BLL.

I'd need it to run Windoz XP so that ARM wouldn't cut it.

This thing is just to replace me having to be there personally. It will be powered only when needed, likely 3 or 4 times in its life. It doesn't have to operate in high temps, nor be "industrial".

The Avantec units are very nice, but way too expensive coming in around $900.

I'm considering a Netbook as you can find them for about $250 and they provide a screen and keyboard too!

The big hitch is shaping up to being the net hookup.

Picture the whole thing setup so you could open it up, turn it on, and access the three loaded and tested apps. Using VNC I could connect to this thing from far away and use it to upload updated code to, say, the PLC.

The issue is that hookup. A typical place has a router hooked to the web that serves the facility. I can't just punch through that router and its firewall unless it's set up with an open port. It's not hard but most places don't have someone around who's router nimble... I haven't cracked this problem. :(

Keith Cress
kcress -
 
I think there are two ways you can do this. But you have painted yourself into a corner on remotely supporting this panel.

The only bad thing I see is you wont be able to get access to your HMI due to that usb connection. Can you change to a switch inside your panel have both PLC and HMI communicating on ethernet? Probably not but if you remote support this would be where you need to go to as far as communications arch in the future.

You need some seperate module that does RS232 to ethernet. There are already many of this type out there so just select one. An off the shelf type module would be idea. Test the connection in your shop before you send it. Do a VPN test from your home to this panel as a final test.

1st way and less restricted
Have a VPN connection to their plant with all the software on you computer over the internet. The customer would have to drop an ethernet connection to your panel and the network is their responsiblity. Not sure how you can communicate to HMI? Is there a seperate port for programming or is it the same USB?

2nd more paranoid customers
Have a server provided by the customer with all software to make changes with the latest files on it. You vpn to this box to connect to your panel. Also customer reponsible for this network.
 
VE1BLL; Wow that's cheap. Someone is giving that away free. To bad an editorial error stating "PC" won't have it running WinXP. :(

Cdude:

Yeah! That's where I want to go with this.

Essentially VNC ( lets you run a PC from another one elsewhere. I used to run embedded controller debugging at my office from home. That way I could check slow test results and change parameters from home without going back to the office for 10 minutes of work every few hours.

One time I knew my son was there working on something and listening to music. I ran the volume slider up and down remotely. Freaked him out. mwahaahHAAHAH

Anyway, the netbook I'd probably mount on the back of the door would be fully capable of running the loaded HMI programming tool and the PLC development tool. With VNC loaded on it I'd just need to connect to it from my location and I'd be able to essentially see the screen, press any keys, and run a mouse. Just like I was standing there. This would allow me to update both the HMI and the PLC. It would also allow me to "watch" the PLC for troubleshooting if needed.

Pretty slick I think. I can support their development without charging them for 6 hours of driving each time. Their cost would be the effort of draping a CAT5 cable from a port over to the netbook and turning on the netbook. AND, they'd need to do what they have to to allow me access to that 'port'. Possibly provide me with a VPN or not. If they had to type something on the netbook to open the channel that would be fine too. I wouldn't be changing anything in the panel without their requesting it and them CAT5ing it anyway.

Concerns are that they don't have a VPN capable router or someone capable of opening a port thru the router.



Keith Cress
kcress -
 
I used to do very similar applications, using WebEx (a paid service). My application was remote tech support for relay testing. Granted, there was generally a person at the other end I was supporting.

I displayed this technology to my company in 2007, by controlling a PC / Test Set / Relay in the US by a PC in Europe. It worked quite well.

I believe the Microsoft SW will do the same, is standardized and free. It's the Cyber security problems you may run into. If as you described, will have the plant folks make the Cat5 connection and boot up the netbook to make the changes, this may ease the pain.

One thought here...what I did was to call the remote PC and then have them give me remote control. What if you had the customer do the same (reverse of what you are describing). This may get you around the router port problem. IOW, client doesn't have to have a port open waiting for a call. They make the call to you.
 
Thanks smallgreek. Your suggestion makes good sense. Since this would only be used when they asked me to use it, I see zero security issues. And I think Windoz lets a remote computer take it over, if offered, by the local user which would get it past all the router issues. Great!! Thanks.

Keith Cress
kcress -
 
Cyber security is something to watch out for. There are bots continuously trolling for open VNC ports. I once opened a port across the internet and got a virus through the VNC port within a minute. Luckily it was a VNC port no a Mac and the virus targeted PCs, so I only had to delete it after I found it.

Z
 
zappedagain,
I agree. Make sure you put a strong password on a internet facing vnc server. I have thousands of failed login attempts that show up in windows event viewer. Mostly Asian and Eastern European country IP addresses.
 
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