Using I/O module in Class 1 div1/2

[scorp]

Hello,

I am looking at simplifing a unit that usually will sit in a class1 div2 area but sometimes may be in div 1. It is usually used for a few weeks at a time then ships to other sites.

Generally we have 4 - 6 cables with current loops between it and another unit. What I am looking at doing is reducing the cabling so our techs can reduce the amount of exposed cabling and reduce chances of faults from bad connections.

I am looking at mounting a plc I/O on the unit and hardwiring the loops to the plc. Then running an ethernet connection to the PLC processor on another unit. Now the PLC and the current loops will require a cable providing 24V and there will be another cable for the ethernet. Can I put the PLC within a Class 1 div 1 rated explosion proof container then use an armored cable for the 24V supply and use IP68 rated ethernet connectors that cover RJ45s and use instrinsicly safe ethernet barriers. Then using the explosion proof glands to run the 4 -20 ma loops throughout the unit.

I thought about using a purge, but then I would have to run instrument air to the unit, which can be a pain. Any suggestions or do I need to give more information?

Thanks

 

[weressl]

Hello,

I am looking at simplifing a unit that usually will sit in a class1 div2 area but sometimes may be in div 1. It is usually used for a few weeks at a time then ships to other sites.

Generally we have 4 - 6 cables with current loops between it and another unit. What I am looking at doing is reducing the cabling so our techs can reduce the amount of exposed cabling and reduce chances of faults from bad connections.

I am looking at mounting a plc I/O on the unit and hardwiring the loops to the plc. Then running an ethernet connection to the PLC processor on another unit. Now the PLC and the current loops will require a cable providing 24V and there will be another cable for the ethernet. Can I put the PLC within a Class 1 div 1 rated explosion proof container then use an armored cable for the 24V supply and use IP68 rated ethernet connectors that cover RJ45s and use instrinsicly safe ethernet barriers. Then using the explosion proof glands to run the 4 -20 ma loops throughout the unit.

I thought about using a purge, but then I would have to run instrument air to the unit, which can be a pain. Any suggestions or do I need to give more information?

Thanks

You can ship a compressed air cylinder with the purged panel.

 

[petersonra]

XP boxes are the pits.

Go with a purged system.

If there is no air available in the area it is installed, ship a pre-pressurized tank with it.