Thin client as "monitor" for HMI/SCADA ?

Hi.

I am thinking about how to provide a monitor in case I have a PC (for example for the HMI/SCADA) installed in the control cabinet. The PC itself is a DIN-rail embedded PC with Windows 7 embedded.

The distance may be too much for a DVI and USB connection for the monitor and keyboard and mouse.

I am thinking about using a thin client PC as the monitor for the embedded PC.
The thin client could use RDP for example, for remotely controlling the embedded PC, or maybe VNC.

Has anyone done something similar ?
Anything to be aware of ?
Something like users that have to be setup on both embedded PC and thin client. And maybe startup issues.

Siemens have some "Industrial Thin Client" PCs, but these are like Panels, i.e . to be installed in a cabinet door or cabinet.
But I would prefer just a regular monitor that will look normal on any desktop, rather than a panel that has to be installed in its own housing.

Do you really want a whole PC? Can't you just use a Video/USB extender over CAT5 or CAT6 cable? Much cheaper, and usually more reliable.

Example Linky.

I have used both concepts you talk about.
The Siemens ITC is great for a touch screen option, a few issues I have found.
If you loose a connection the only way I have found to reconnect is to re-power the unit, it will reconnect fine after.
There is a really annoying task-bar that always seems to be in the wrong position on the screen so I always disable it.
It has all options to connect RDP, VNC etc.

Another option is this
http://www.marketwire.com/library/MwGo/2015/8/20/11G051325/Images/ACP_ThinManager_Ready_Hazardous_Areas_Thin_Clients-1093995594375.jpg

Good luck, the concept works very well.

Thank you both.

rdrast, can you fill in something about why you think that a KVM extender is more reliable ?
What I do not like about a KVM solution is that you need special hardware at both ends.
edit: I have done it before, and I found it a bit messy with all the cables and power supplies etc. at both ends.
But I am not totally against it of it is more reliable than a thin client PC.

edit again: No I dont need "a whole PC". With thin client I mean something like this: http://www.fujitsu.com/fts/products/computing/pc/thin-clients/futro-a300/


adamplc, the reconnection issues you mention, was that with RDP, VNC, or both ?

edit: I find that a thin client with RDP or VNC would be a tidy solution, with just the LAN cable to the embedded PC needed.
And if something goes wrong with the thin client, you can just quickly setup another PC for RDP or VNC.

JesperMP,
if the network goes down for maintenance on the client etc I have to restart the ITC to reconnect. They are all RDP connections.
I currently have 9 ITC units so that can be a pain to bring them all backup. If your network will always be running you won't run into this issue.

I also have a WinnCC machine using a similar HP thin client as that Fujitsu, the thing I love about these clients is if the hardware goes obsolete you can buy anything to get you running again, even a laptop.

A PC is just that, another PC. Another video card, another HDD/SSD, another operating system, a lot of stuff just to handle a display and mouse.
I've used the KVM extenders for two decades without any issues, going all the way back to VGA and Serial Mice. They can either be IP based or not; usually you can go at least 300 feet just over a dedicated CAT 5 cable.

Google,

https://www.milestek.com/blog/index...-over-lan-extenderconverter-product-showcase/

similar to KVM

If you go the thin client route (ex. Wyse box) it gives you the best future support.
Should anything go wrong with the thin client box, you can use any other thin client box to replace it. Or, like you mentioned just use any PC to replace it.

If you use a KVM extender, either you need to buy two of those (one for each end) or you need to install software on the host PC. Should anything go wrong then you need to replace with the same/compatible model of KVM.

KVM is easy to setup.
Thin client keeps you vendor neutral.

Use TightVNC.

We tried a KVM extender on a project and it was just too long for stable signal and the entender wasn't cheap either. Ended up buying a little brick PC for $200 and used VNC instead. Works great.

adamplc said:

if the network goes down for maintenance on the client etc I have to restart the ITC to reconnect. They are all RDP connections.
I currently have 9 ITC units so that can be a pain to bring them all backup. If your network will always be running you won't run into this issue.

Click to expand...

You are saying that if there is an active RDP, and if the connection LAN goes down, for whatever reason, RDP wont be able to reconnect without a reboot of the thin client ?

We normally split the LANs into our machine LAN, and the customers own LAN. We are in full control of our own LAN. We would never allow our system to be dependant on the customers IT department.

But .. even if we are in full control of our LAN, I can imagine that if any network issue means the thin client must be rebooted, it will be a hassle if not a dealbreaker.

rdrast said:

A PC is just that, another PC. Another video card, another HDD/SSD, another operating system, a lot of stuff just to handle a display and mouse.

Click to expand...

If you look at the thin client PC I linked to, you can see that it is actually very simple. The one I linked to can even by mounted piggy-back on a monitor, so it will look very clean and tidy. The thin client comes ready to run with Linux on board. So there is nothing to maintain.

It may be a little more expensive than a KVM solution (*), but the extra cost is worth it to us if we can omit the KVM box + cables + power supply in the control cabinet.

If I shall convince my colleagues, it has to look as simple and neat as possible.

*: Or is it ? The Fujitsu thin client I linked to costs approx 200 €. Can you get a KVM extender for semi-long distances for that ?

We run our SCADA on our server and use a thinclient for connection. The thinclient connects to RDS and the SCADA viewer is connected with Remote app on the server. Works great!

I had done one application with multiple thin clients and come to conclude that nothing was to gain for all of the additional software setup and maintenance.

I have also used the Beckhoff panels with a 25 meter DVI cable. Their panels have electronics in them that can amplify and use weak DVI signals without the need of an amplifier/repeater. For example, the CP79xx control panel with DVI/USB extended interface. They also support USB touch screen by using a USB to CAT5 adapter that comes with their DVI/USB cable kit.

According to their web site you can use up to a 50m DVI cable:

http://www.beckhoff.com/english/industrial_pc/cp_dvi.htm?id=451687892053394

JesperMP said:

You are saying that if there is an active RDP, and if the connection LAN goes down, for whatever reason, RDP wont be able to reconnect without a reboot of the thin client ?

We normally split the LANs into our machine LAN, and the customers own LAN. We are in full control of our own LAN. We would never allow our system to be dependant on the customers IT department.

But .. even if we are in full control of our LAN, I can imagine that if any network issue means the thin client must be rebooted, it will be a hassle if not a dealbreaker.

Click to expand...

Yep if the RDP connection is dropped I cannot get it to automatically reconnect.
Real pain in the arse, but if you have a stable connection you won't see this problem.
I haven't looked into the task window as I had to remove it due to it taking up sections of the screen.
This is all related to the Siemens ITC's.
There is a setting within the configuration utility to resume connection but it doesn't work.

Thanks adamplc, good to know.