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UL approval question

UL approval question

UL approval question

(OP)
I'm researching instruments and I'm relatively new to this line of work. I hope my question is easy to answer.

If a measuring instrument is UL listed and classified as for example, Class 1, Div 1 & 2, Groupe E, F, G (Ashcroft B-Series Switches), does this mean it is a UL approved device?

I heard it doesn't necessarily have to. It may just be a classification but not necessarily approved (like a FM approval).

RE: UL approval question

Does it have a UL label on it? If so, it is approved by UL for these areas with no other requirements (UL "listed"). If it has a U backwards R label, then it is UL "recognized" which means you need to read the installation instructions carefully as there is some requirement, from UL, for the product to be fully UL "listed".

RE: UL approval question

Oh, one other thing. There is a number on the label which tells you the standard that UL is approving this too. Believe it is like 5 numbers or so but it is right on the label. Look this number up on UL.com and it will tell you what standard the product was tested too and you should then know if this is what you need.

RE: UL approval question

Technically the hole piece of equipment should be UL Certified (which will be expensive).  Usually all an inspector is looking for is a UL sticker on the power supply box.  If your machine has an external breaker box on it, get that certified (I think it would be the UL 50 Standard) and that would probably satisfy him to connect power.  

I deal with this allot, we build outdoor power supply cabinets for cable and telecom industry.  Most inspectors require the Breaker Box inside by Certified (UL or CSA).  Technically the whole cabinet should be certified but they are really interested in seeing the sticker at the power connections.

Fill what's empty. Empty what's full. And scratch where it itches.

RE: UL approval question

eSung 911,

The word "Listed" means the device has been evaluated to all possible hazardous related to a particular category.  Listed products can are stand alone products that need no further investigation.  If you see this on a a Hazarodus Locations product like the one you referenced in your example that means that the applicable ordinary locations standard and hazardous Locaions standard were evaluated.  

The word "Classified" means that the product has been evaluated to only certain hazards.  i.e. Classified Enclosures.  Sometimes the ordinary location is involved sometimes not.

Like the gentleman mentioned the backwards R with the U means the device is a "Recognized Component", that has "conditions of acceptability".  The conditions of acceptability express limitations on the certification and have to be evaluated in the end products use.

"Unlisted Component" a device which is for use with another part made by the same manufacturer.  Doesn't have to have any markings at all.

The 5 digit lettering that appears on the products label is called a "control number" and has nothing to do with what you may find on the UL web site. The control number is specific to a manufacturer and its UL's way of designating a listing to a certain manufacturer.  The CCN, Category Conrol Number, is what you want to use if you go to UL's website to look up a listing, but this usually is not on the products label.  If you go to UL's website, www.ul.com, a lot of this information should be detailed.

RE: UL approval question

Hi, I am part of a team that is currently designing and constructing a Mailbox Style Vacuum Chmber System that needs to be UL certified.  Can anyone recommend to me a company that would help me get this certification?  I am new to this line of work.

Thank you

RE: UL approval question

This thread is ancient. Not sure why someone thought to revamp it.

Its best to start a new thread but certainly UL itself does testing. There are third party test houses who could probably do it too. I would start with UL so you know which standards apply then solicit a third party if you want. It may get it listed quicker than UL but the cost probably won't be to much different.

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