Class 1 Division 1 w/PanelviewPlus

[JZerb]

If you were to take a Panelview Plus, mount that in an enclosure that is purged by a purge unit that takes the environment from Class 1 Division 1 down to a non-hazardous area. Does that now make the Panelview Plus sufficient for the area? Or would one need an intrinsically safe touch screen setup?

 

[BlueAltezza]

I think the PV is only rated for Div II, so my initial thought would be you can't use it on a Div I enclosure with the screen exposed.

I have seen hmi's mounted to pressurized enclosures with their own access doors (via key) - which should essentially just be an extension of the main enclosure if sealed properly.
I believe the screen must be behind a protective window to meet the c1d1 requirements - unfortunately that means it can't be touched during normal operation.

I'm no expert, so hopefully someone with more knowledge can chime in!

 

[JZerb]

The access door was an idea tossed around where I work. That you could do something in which the operator could use the HMI while the machine was not in operation. Then once the machine had to be used you’d have to close the access door and use a push button to start the process. Wasn’t sure if that was a legit way of doing it or not personally.

 

[cardosocea]

The access door was an idea tossed around where I work. That you could do something in which the operator could use the HMI while the machine was not in operation. Then once the machine had to be used you’d have to close the access door and use a push button to start the process. Wasn’t sure if that was a legit way of doing it or not personally.

I would say for that to fly, you probably would have to hard wire the power supply of the panel to the access door switch. OSHA or equivalents don't tend to accept pinky swear as a control measure.

 

[James Mcquade]

panelview terminals are rated class 1 div 2, class 2 div 2.

per Allen Bradley, you cannot mount a panelview terminal in an enclosure that is purged or pressurized, the screen will break. this was from 8 years ago when I needed to do just that. we had to end up using hazardous pushbuttons, switches, and indicator lights.

james

 

[JZerb]

panelview terminals are rated class 1 div 2, class 2 div 2.

per Allen Bradley, you cannot mount a panelview terminal in an enclosure that is purged or pressurized, the screen will break. this was from 8 years ago when I needed to do just that. we had to end up using hazardous pushbuttons, switches, and indicator lights.

james

Interesting. I have never directly asked anyone at AB if I could even do what I described originally, just figured it would be ok. I’ll be sure to call AB tomorrow to verify that it cannot be done that way. If that truly is the case I’ll be ruining a few people’s day tomorrow. Thanks for the info!

 

[Bullzi]

Any chance you can move the PV to a Div. 2 area?

 

[rupej]

Another question- does anyone make a C1D1 touchscreen? Or screen with programmable buttons?

 

[JZerb]

Any chance you can move the PV to a Div. 2 area?

Unfortunately I cannot.

Another question- does anyone make a C1D1 touchscreen? Or screen with programmable buttons?

Only thing I found was Pepperl & Fuchs makes a touch screen that has the capability to be C1D1 if you order the intrinsically safe touch screen option. Then in my case I’d need a thin client and a license for either machine edition or site edition to run on the PC I’d assume.

 

[Jeff23spl]

Anything protruding outside of your pressurized box will need to be cl1 div1 rated.

About the access door, that one is the same as the whole panel door. For div1 it would need to shut down the panel and you will need to have some means to confirm the internal parts got enough time to cool down before opening....

for every ten request for classified panels, at least 9 of them finally ends by moving all possible electric components outside of the zone and keep some push button and lights.

 

[cwal61]

They do make C1D1 keyboards. I have put PC's inside purge panels in C1D1 Locations For HMI. Never heard of screen cracking issue. You purge panel at 60 psi for time according to cubic feet of panel and then the system maintains like 1/2 pound of pressure and monitors cabinet pressure vs. atmosphere.

 

[JZerb]

Anything protruding outside of your pressurized box will need to be cl1 div1 rated.

About the access door, that one is the same as the whole panel door. For div1 it would need to shut down the panel and you will need to have some means to confirm the internal parts got enough time to cool down before opening....

for every ten request for classified panels, at least 9 of them finally ends by moving all possible electric components outside of the zone and keep some push button and lights.

Ya we do have a lot of people ask and then in the end they don’t want to pay so plans get changed.

How about a customer or someone saying “Well the HMI is above 18” from the floor so it doesn’t need to be C1D1 since vapors fall”

 

[James Mcquade]

We have always used purge units sized for the enclosure.
it's been 8 years and I have forgot which ones we used at my former job.

james

 

[Jeff23spl]

They do make C1D1 keyboards. I have put PC's inside purge panels in C1D1 Locations For HMI. Never heard of screen cracking issue. You purge panel at 60 psi for time according to cubic feet of panel and then the system maintains like 1/2 pound of pressure and monitors cabinet pressure vs. atmosphere.

You never put 60psi or you will end up with a round shaped box...(just multiply your panel surface in square inch by psi to know the applied force)

There is a vent valve to exhaust any excess pressure to do the rapid air exchange.

If the whole thing including the screen is inside the panel with a differential pressure below 1psi, is it worst than using it a sea level at higher atmospheric pressure ? i wouldn't be worried as long as there is a vent.

 

[Jeff23spl]

How about a customer or someone saying “Well the HMI is above 18” from the floor so it doesn’t need to be C1D1 since vapors fall”

Not sure all gaz are heavier than ambiant air...
But anyway, i would just ask them to have this to be approved and signed by the same engineer that designed the area to be classified....