Non-rated components within hazardous locations using enclosures

[scorp]

Hello. I have tried looking up this topic quite a few times and see different responses or requirements;

What I have is a proportional solenoid driver module, designed for mounting on a din rail, that will control a solenoid in a class 1 div 1 area. The solenoids are marked UL for class 1 div 1. The driver module made by the same company is not rated and is only marked CE which of course means nothing for us. What I am looking at doing is placing the driver module in a class 1 div 2 area and running the signal with approved cabling and glands to the solenoids.

Now since this isn't rated for installation in div 2, I am unable to put it in our PLC panel that is div 2. We have been told we could possibly put it in a seperate explosionproof enclosure and use it. We may have to possibly get the whole assembly tested and certified to do this.

What I am trying to find out is what is involved, and if there is really a need to have the assembly tested if we are going to use it in an EX enclosure with all fittings and cables approved for enclosure. We have no issue in purchasing the more expensive enclosures and parts, it is mainly a time factor in getting this equipment ready.

 

[petersonra]

You can put general purpose electrical equipment in an XP enclosure and put it out next to the solenoid if you want to. That is pretty much what XP enclosures are for. if you want the assembly UL listed go to a UL control panel shop that does UL 698A control panels.

Incidentally, a lot of stuff like what you are describing is made in versions that are UL listed for use in C1D2 areas. Maybe it is just a matter of a different module.

In any case, there may be an issue of getting the XP assembly UL listed if the part inside is not itself UL listed.

 

[scorp]

That is what a lot of us thought, but just wanted to confirm. Dealing with one enclosure manufacturer, they would only populate with UL listed or approved components.

Our equipment is considered temporary installation, and will move from on oil field location to another, so we want to make sure we are safe and in compliance for the multitude of juridictions out there.

 

[petersonra]

That is what a lot of us thought, but just wanted to confirm. Dealing with one enclosure manufacturer, they would only populate with UL listed or approved components.

Our equipment is considered temporary installation, and will move from on oil field location to another, so we want to make sure we are safe and in compliance for the multitude of juridictions out there.

It sounds like you were dealing with a UL 698A shop. it is not real easy to put a non-UL part in a UL listed panel.

They can probably still build you the box but just skip the UL label.

You might want to take a close look at your customer's specs. A lot of them require listed components.

 

[scorp]

We service and run our equipment on the customer's locations. Generally as long as we meet NEC then they usually don't have an issue with us. If there is a need to certifiy our equipment as a whole, we can probably do that, it would just take a long time and we won't be able to make changes to the design.

I was able to confirm with other sources that the XP enclosures were suitable as long as we make sure that we pay attention to the temperature of the components inside. We have a builder that can look into that for us.
Are there any specific NEC guidelines or common mistakes on XP enclosures that I should keep mind of?


This is definately an eye opener :dunce:. We also deal with Atex, so there is a lot of items we have to look at. I prefer to be designing processes and programming, this compliance stuff isn't fun but it is an important need.

 

[petersonra]

Are there any specific NEC guidelines or common mistakes on XP enclosures that I should keep mind of?

The NEC guidelines are all found in 500 and 501.

There are a lot of common mistakes made, but they are as often as not things people do that do not need to be done (like extra seals) but that do not hurt anything, but just add extra cost unnecessarily.

get the XP enclosures drilled at the factory for whatever conduit attachments you need. it is moderately painful to do drilling in the field and is likely a violation of the UL listing if that matters.