Installation of Door-Mounted HMI in a z-purged enclosure in a C1D2 Environment.

[XL Automation]

The use of the purge effectively makes the interior of the enclosure a non-classified area in this case. However, can a Nema 4X HMI without a touchscreen (and without C1D2 rating) be installed in the enclosure. I could argue that the HMI is isolated from the environment by its NEMA rating, and the HMI "guts" are inside the enclosure.

Opinions?

Thanks,
Michael

 

[petersonra]

I had a long chat with an AB product manager about this once. It turns out that some of the panelviews with membrane keypads cannot take the pressure from the backside. It causes the membrane to delaminate.

 

[XL Automation]

I had a long chat with an AB product manager about this once. It turns out that some of the panelviews with membrane keypads cannot take the pressure from the backside. It causes the membrane to delaminate.

Yes, this certainly makes sense, and thanks for the feedback!

But what about industrial monitors? I probably should have mentioned my specific case, but I was trying to be somewhat generic, and unwittingly holed myself into a non-touchscreen HMI, which would have to have a membrane keypad for operator input. In my case though, I want to install a standard industrial monitor without a touchscreen in the door. There will also be a separate C1D1 keyboard (let's ignore this for now). So, I THINK that the only issue would be whether the exterior of the monitor would even need classification at all, since there is only exposed stainless steel and glass that is NEMA 4X rated.

 

[petersonra]

Why not just buy a C1D2 rated monitor? they are readily available. then you would not need to screw around with a pressurization system.

 

[XL Automation]

Why not just buy a C1D2 rated monitor? they are readily available. then you would not need to screw around with a pressurization system.

There is far more in the panel than just a monitor.