What PLCs are being used in coal mines?

[SNP]

Thank you Jesper!

Try to google for "explosion proof enclosure".

Of course I have done it and also googled "explosion proof enclosere coal mine". Alas, still I haven't find even one well-known producer.

But be warned that there is a BIG difference between EEX-d and EEX-e for example.

Yesterday, indeed, even to save my own life, I would be unable to say what is the defference. But today I'm much more informed.

You cannot just stuff a PLC inside an EEX-e enclosure and then call it explosion proof.
And I think that it is impractical to install a PLC in an EEX-d enclosure.

I rather plan to place an RTU, remote terminal unit than PLC. All "brains" would be on the surface.

I think you should start with some basic training in EEX terms and techniques. It is too early for you to search for specific parts.

You are right Jesper, it is too early. However, real life is to complex and fast-running.

 

[JesperMP]

STAHL is a very well known name for EEX equipment:
http://www.stahl.de/en/start.html

They also have a short description about EEX:
http://www.stahl.de/fileadmin/Dateien/download_publikationen/Grundlagen_Ex_en_web.pdf

 

[TimWilborne]

I understand that it is silly and even stupid question but is anybody aware about reliable Western producer of explosion-proof encosures that are being used in coal mines?

For me it is the main question.

Now things may have changed in the coal mining industry or maybe I just worked with an over cautious mining equipment manufacturer but I'm unaware of any enclosures that you can buy off of the shelf that can be used in the coal mining industry, at least not on the equipment itself.

Not only does it have to be explosion proof, but they also must deal with debris hitting them and roof collapses. We used to make them at a company I worked for. Most were 1/2" to 1" thick depending on the size of the enclosure, solid welded on the outside and stitched on the inside, and gusseted to help them withstand external forces.

 

[JesperMP]

I rather plan to place an RTU, remote terminal unit than PLC. All "brains" would be on the surface.

Then consider one that is 100% EEX-i.
For example Siemens ET200iS is a Profibus solution where everything is intrinsically safe.

You could then put that inside an EEX-e box for basic mechanical protection.
And then put the EEX-e box under a reinforced concrete roof to protect against caveins.
OK I am way out my league here.

 

[SNP]

STAHL is a very well known name for EEX equipment:
http://www.stahl.de/en/start.html

They also have a short description about EEX:
http://www.stahl.de/fileadmin/Dateien/download_publikationend /Grundlagen_Ex_en_web.pdf

Great!

Start reading...

... and I was told that R.STAHL produces enclosures only for zones 1 and 2. But I need them for zone 0.