Remote operation

[Jcooli09]

My company has come out with very strict quarantine policies to mitigate the risk of the coronavirus. Many of our terminals have only a manager and operator on site, so a quarantine will completely kill the facility.

In order to avoid this we are considering remote loading. This is pretty easy at the PLC controlled terminals, but I have 2 facilities which still use physical buttons and large relay panels.

To get around this, I've been considering using remote I/O controlled by one of the processorts at another facility. I would just rig the outputs in parallel with the buttons and switches, and connect the indicators to the inputs. I could create an HMI which looks exactly like the control board and the we could load trucks.

Another option would be to install a MicroLogix with a little IO and do the same thing, but the control would be local.

I'm looking for opinions about this, and maybe options for less expensive processors and HMI software. My company uses Rockwell/AB exclusively, but in this case I could get away with something different if it's cheaper, easier, or quicker to get, provided we don't sacrifice reliability too much.

Any opinions will be welcomed, I know some of you guys are gurus and I'm hoping you'll critique the idea.

 

[mk42]

I'd go for local control over a remote PLC. In my experience, general IO protocols and VPNs don't work very well together, unless you're using an RTU specifically designed for it. You could still have the HMI at a remote facility if you wanted.

 

[GaryS]

By remote terminal do you mean that they are on the same property distance apart and you can just walk from the main operator station to the loading station or are they miles away ?

It is all doable. I would consider a small plc at each relay panel networked together just having remote IO I think would be dangerous what is going to happen if communication is lost there need to b some processing at the local site
Consider a micro 800 plc small cheap and supports communications
This would be an interesting project to do there are many ways to set it up.

 

[Timbert]

Many of our terminals have only a manager and operator on site, so a quarantine will completely kill the facility.

I do have to wonder about the logic of trying to change this at this point. With only two people at a facility you can't get much better social distancing than that. They will likely have close contact with more people at home. I'm assuming you would restrict the drivers of trucks from your workers.

This seems more like a problem with an inflexible policy than a technical issue.