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Double insulated versus grounded plug

Double insulated versus grounded plug

Double insulated versus grounded plug

(OP)
Our safety team here at our facility is hell bent on removing all of our desk type fans because the plugs aren't grounded. Where they are made of plastic, most of our department feel this is over the top as far as safety goes.Most of them are probably double insulated anyway. Is there any reference in the NEC or OSHA that anyone can let me know about and help to straighten this problem out??  Thanks, Ballpeen.

RE: Double insulated versus grounded plug

Purchase some in-line GFI protection devices and everyone should be happy.

RE: Double insulated versus grounded plug

I believe that there is a reference, somewhere, to the fact that if an item is double insulated that it does NOT need to be grounded.  

The above comes from a discussion I remember back in my High School Electricity-I class.  We also discussed what double insulated means and IIRC it means that both the hot and neutral lines are switched (I suppose in case it is plugged in backwards) AND there is an insulation barrier to the case, which is generally non metallic.

You might have an easier time finding a UL standard to this effect than finding an NEC standard, though typically UL tends to follow NEC pretty close.

RE: Double insulated versus grounded plug

If double insulated, it's actually quite important NOT to ground it.

The nice thing about double insulated appliances is that you can operate them safely outside the equipotential zone without risking a shock should the protective conductor start to float above local earth.  Grounding them removes that protection.

Having said that, I wouldn't be at all keen on appliances that are neither grounded, nor demonstrably double-insulated.

A.

RE: Double insulated versus grounded plug

Ungrounded, un-doubleinsulated used to be the norm.  Everytime you touched a metal surface you could feel the AC coupling buzzing into your fingertips.

TTFN

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RE: Double insulated versus grounded plug

Look for a UL certification on the fan??

RE: Double insulated versus grounded plug

(OP)
  Most of these fans are old enough so that the labeling is missing, which makes it difficult to find a reference for them. I contacted OSHA by email and they weren't too specific on this either. Most of the wording that I got was too confusing. I wish they put it down in laymen's terms.They said that I need to send them something in a letter form, before I could get a specific answer. I guess the best way is to purchase a bunch of GFI's to accommodate these type of fans and be done with it. Don't get me wrong, I'm all for safety. I just feel that certain people are trying to make a name for themselves at our facility at the expense of others, if you get my meaning.

RE: Double insulated versus grounded plug

Since your fan is located in a workplace it will need to be approved by an NRTL such as UL, CSA, TUV etc. If the fans are old the best option is to probably replace them with fans that are approved.

Cheers,
Nick

RE: Double insulated versus grounded plug

Yeah.

Something with an approval tag.

Like from China...  

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: Double insulated versus grounded plug

(OP)
Well said itsmoked!

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