Results 1 to 27 of 27
  1. #1
    Join Date
    Mar 2007
    Location
    Chicago, IL
    Posts
    2,797

    Default Equipment Ground Requirements at Home Office Equipment Receptacles

    My notes say :


    Some equipment is not allowed to be connected to ungrounded receptacles. Even though all the receptacles have been changed out to grounded type and they are all given GFCI protection, if there is no actual equipment ground conductor connected to the grounded terminal of the receptacle, then a number of cord and plug devices can't use those receptacles.


    I know that (for example) cord connected office equipment such as computers and printers with grounded plunges fall into this category, but I can't find the code reference that defines such equipment.



    Anyone know what it is is?


    Similar Threads:
    NHIE Practice Exam
    Michael Thomas
    Paragon Property Services Inc., Chicago IL
    http://paragoninspects.com

  2. #2
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    26,250

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by Michael Thomas View Post
    I know that (for example) cord connected office equipment such as computers and printers with grounded plunges fall into this category, but I can't find the code reference that defines such equipment.

    NEC 110.3(B) Installation, and Use of Equipment. It is required to be installed and used in accordance with its listing and labeling.
    - 110.3 Examination, Identification, Installation, and Use of Equipment.
    - - (B) Installation and Use. Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  3. #3
    Ted Menelly's Avatar
    Ted Menelly Guest

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    In every report under electric service and branch circuits I tell all clients that if nothing is done to upgrade the electric that they should and must (for their own sake) upgrade the receptacles to any and all appliances, TV, entertainment equipment, office electronics etc etc etc. I express it even heavier than the entire electric system for the fact that most homes do not get the upgrades before the buyer moves in.

    The equipment is to expensive. Who cares about a lamp??


  4. #4
    Join Date
    Jul 2008
    Location
    Snowbird (this means I'm retired and migrate between locations), FL/MI
    Posts
    4,086

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Any equipment that states in its labeling/listing that it is required.
    The presence of the grounding cap is evidence that it requires connection to equipment grounding to utilize it in accordance with its listing.

    This is why all those "downstream" receptacles which are not grounded but are GFCI protected "upstream" by a GFCI receptacle must be labeled "NO EQUIPMENT GROUND".

    The Code makes reference that items be used in accordance with their listing, not contrary to their listing, this includes devices which are cord-and-plug-connected.


  5. #5
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    26,250

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by H.G. Watson, Sr. View Post
    Any equipment that states in its labeling/listing that it is required.
    The presence of the grounding cap is evidence that it requires connection to equipment grounding to utilize it in accordance with its listing.
    ...
    The Code makes reference that items be used in accordance with their listing, not contrary to their listing, this includes devices which are cord-and-plug-connected.
    Which is covered by this post from above:

    Quote Originally Posted by Jerry Peck View Post
    NEC 110.3(B) Installation, and Use of Equipment. It is required to be installed and used in accordance with its listing and labeling.
    - 110.3 Examination, Identification, Installation, and Use of Equipment.
    - - (B) Installation and Use. Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.


    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  6. #6
    Join Date
    Jul 2008
    Location
    Snowbird (this means I'm retired and migrate between locations), FL/MI
    Posts
    4,086

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by Jerry Peck View Post
    Which is covered by this post from above:
    No actually it wasn't. I summarizied from other articles also and the White Book. I covered more than your meger citation.

    There was a post that followed your prior post. You aren't the guru and ultimate authority you seem to think you are.


  7. #7
    Ted Menelly's Avatar
    Ted Menelly Guest

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Hmmmm

    So, after all that the equipment or appliance would not have a plug on it with the ground prong unless it was meant to be grounded as such.

    All that technical wizardry to say the same thing I said with out all the tech code wizardry.

    Some things are just to simple.

    The other thread with the Microwave. Most may only need x to run but start up is much greater. As far as I ever new a micro always needed its own circuit and not on a GFCI

    Some things are just to simple.

    I do like reading all the rehash thow. It does keep me on my toes and in the know.


  8. #8
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    26,250

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by H.G. Watson, Sr. View Post
    No actually it wasn't. I summarizied from other articles also and the White Book. I covered more than your meger citation.

    There was a post that followed your prior post. You aren't the guru and ultimate authority you seem to think you are.
    I see back to your cheerful and nice ways, huh?

    No one said or implied that I am the ultimate authority, nor even the intermediate authority, it is also very clear that you are not the ultimate authority either, nor are you even the intermediate authority.

    My post of NEC 110.3(B), though PRECISELY covers what is being discussed and is a suitable and satisfactory code reference as one does not need to, nor are they required to, cite each and every code section which is applicable to a given condition.

    Given the controlling condition which is OBVIOUS in the above referenced installations - the installation instructions for the referenced equipment states installation requirements would are not met by the installation (the OBVIOUS part) - then the installations are not in accordance with the requirements of the listing, labeling, and installation instructions ... and THAT is a violation of NEC 110.3(B). Plain and simple.

    You may not like the plain and simple answer, but it is an effective, and accurate, answer. You seem to have a need to try to dazzle us with ... well, whatever it is you are trying to dazzle us with.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  9. #9
    Join Date
    Jul 2008
    Location
    Snowbird (this means I'm retired and migrate between locations), FL/MI
    Posts
    4,086

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by Jerry Peck View Post
    I see back to your cheerful and nice ways, huh?

    No one said or implied that I am the ultimate authority, nor even the intermediate authority, it is also very clear that you are not the ultimate authority either, nor are you even the intermediate authority.

    My post of NEC 110.3(B), though PRECISELY covers what is being discussed and is a suitable and satisfactory code reference as one does not need to, nor are they required to, cite each and every code section which is applicable to a given condition.

    Given the controlling condition which is OBVIOUS in the above referenced installations - the installation instructions for the referenced equipment states installation requirements would are not met by the installation (the OBVIOUS part) - then the installations are not in accordance with the requirements of the listing, labeling, and installation instructions ... and THAT is a violation of NEC 110.3(B). Plain and simple.

    You may not like the plain and simple answer, but it is an effective, and accurate, answer. You seem to have a need to try to dazzle us with ... well, whatever it is you are trying to dazzle us with.
    One doesn't have to look up its listing or instructions, THE CORD CAP SAYS IT ALL.

    The citation Michael Thomas was referring to is (2008 NEC) Article 406, specifically the entirety of 406.3

    Last edited by H.G. Watson, Sr.; 02-26-2009 at 05:49 PM.

  10. #10
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    26,250

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by H.G. Watson, Sr. View Post
    One doesn't have to look up its listing or instructions, THE CORD CAP SAYS IT ALL.

    The installation instructions say it all.

    The other stuff just adds to it.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  11. #11
    Join Date
    Jul 2008
    Location
    Snowbird (this means I'm retired and migrate between locations), FL/MI
    Posts
    4,086

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by Michael Thomas View Post
    My notes say :


    Some equipment is not allowed to be connected to ungrounded receptacles. Even though all the receptacles have been changed out to grounded type and they are all given GFCI protection, if there is no actual equipment ground conductor connected to the grounded terminal of the receptacle, then a number of cord and plug devices can't use those receptacles.


    I know that (for example) cord connected office equipment such as computers and printers with grounded plunges fall into this category, but I can't find the code reference that defines such equipment.



    Anyone know what it is is?
    2008 NEC Article 406, the entirety of 406.3.

    I don't have the OSHA references handy, but if you need them please advise.


  12. #12
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    26,250

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by Michael Thomas View Post
    My notes say :

    Some equipment is not allowed to be connected to ungrounded receptacles. Even though all the receptacles have been changed out to grounded type and they are all given GFCI protection, if there is no actual equipment ground conductor connected to the grounded terminal of the receptacle, then a number of cord and plug devices can't use those receptacles.

    I know that (for example) cord connected office equipment such as computers and printers with grounded plunges fall into this category, but I can't find the code reference that defines such equipment.

    Anyone know what it is is?
    Quote Originally Posted by H.G. Watson, Sr. View Post
    2008 NEC Article 406, the entirety of 406.3.
    Where is 2008 NEC 406.3 does it state that?

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  13. #13
    Join Date
    Aug 2008
    Location
    Maryland
    Posts
    1,899

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Mike,

    This is the Article I was thinking of. I just could not find the time to look.

    Atricle 250.114 has the complete list.


  14. #14
    Join Date
    Mar 2007
    Location
    Chicago, IL
    Posts
    2,797

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by Jim Port View Post
    Mike,

    This is the Article I was thinking of. I just could not find the time to look.

    Atricle 250.114 has the complete list.
    Thanks, GOOGLE turns up:

    The following cord and plug connected equipment is required to be grounded (2005 NEC 250.114(3)), unless protected by a system of double insulation:
    A. Refrigerators, freezers, air-conditioners.
    B. Clothes-washing, clothes drying, dishwashing machines; kitchen waste disposers; information technology equipment ; sump pumps and electrical aquarium equipment
    C. Hand-held motor-operated tools, stationary and fixed motor-operated tools, light industrial motor-operated tools
    D. Motor-operated appliances of the following types: hedge clippers, lawn mowers, snow blowers, and wet scrubbers.
    E. Portable handlamps.


    Michael Thomas
    Paragon Property Services Inc., Chicago IL
    http://paragoninspects.com

  15. #15
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    26,250

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by Jim Port View Post
    Mike,

    This is the Article I was thinking of. I just could not find the time to look.

    Atricle 250.114 has the complete list.

    That does not address Michael's question, that only addresses for when an equipment ground is present.

    Replacement receptacles without an equipment ground present are addressed 406.3(D), which allows for the installation of non-grounding type receptacles and ungrounded-grounding type receptacles which are GFCI protected and labeled with "No Equipment Ground".

    Thus, once one of those receptacles has been installed, per code and are code compliant, then the controlling factor defaults back to 110.3(B) where the equipment is to be installed in accordance with its listing, labeling, and installation instructions.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  16. #16
    Join Date
    Aug 2008
    Location
    Maryland
    Posts
    1,899

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by Michael Thomas View Post
    My notes say :


    Some equipment is not allowed to be connected to ungrounded receptacles. Even though all the receptacles have been changed out to grounded type and they are all given GFCI protection, if there is no actual equipment ground conductor connected to the grounded terminal of the receptacle, then a number of cord and plug devices can't use those receptacles.


    I know that (for example) cord connected office equipment such as computers and printers with grounded plunges fall into this category, but I can't find the code reference that defines such equipment.



    Anyone know what it is is?
    Jerry,

    Again you misread the post. The red cleary asks what certain equipment cannot be used if the receptacle is ungrounded. 250.114 is the list of equipment that MUST be used in grounded receptacles, therefore it DOES answer the OPs question.


  17. #17
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    26,250

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by Jim Port View Post
    Jerry,

    Again you misread the post. The red cleary asks what certain equipment cannot be used if the receptacle is ungrounded. 250.114 is the list of equipment that MUST be used in grounded receptacles, therefore it DOES answer the OPs question.
    Jim,

    Again you misread the post.

    And misunderstand the code.

    The code you cited applies to NEW INSTALLATIONS, the code I cited applies to REPLACEMENTS, which is what Michael was asking asking about, and, equipment CONNECTED TO THOSE REPLACED receptacles, not connected to new receptacles on new circuits.

    If that house were being constructed today, the code reference you cited would be a correct code reference.

    However, the code IN EFFECT AT THE TIME OF CONSTRUCTION allowed for otherwise, thus, the REPLACEMENT receptacles must meet todays (at the time of their replacement) code.

    Otherwise you are saying that every single older home with ungrounded receptacles and circuits IS REQUIRED TO BE RE-WIRED?

    Once installed to code and so accepted (whether or not it actually meets code) and has been given a certificate of occupancy that building is allowed to remain in conformance to THAT CODE in effect at the time of construction for the life of the building and installations. NEWLY installed items are required to meet the code in effect at the time of the installation of such items.

    The NEC only has, as I recall, *two* retroactive requirements:
    - 1) In the event of over-fusing with Edison base fuses, those are required to be adapted over to the Safe-T-Fuse adapters.
    - 2) In the event a receptacle is replaced which is now required to have GFCI protection that replacement receptacle is required to have GFCI protection.

    If there are others, I am sure Fred or Roland will post them and update what I have posted.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  18. #18
    Join Date
    Aug 2008
    Location
    Maryland
    Posts
    1,899

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by Michael Thomas View Post
    Thanks, GOOGLE turns up:

    The following cord and plug connected equipment is required to be grounded (2005 NEC 250.114(3)), unless protected by a system of double insulation:
    A. Refrigerators, freezers, air-conditioners.
    B. Clothes-washing, clothes drying, dishwashing machines; kitchen waste disposers; information technology equipment ; sump pumps and electrical aquarium equipment
    C. Hand-held motor-operated tools, stationary and fixed motor-operated tools, light industrial motor-operated tools
    D. Motor-operated appliances of the following types: hedge clippers, lawn mowers, snow blowers, and wet scrubbers.
    E. Portable handlamps.
    Michael seems to agree that this is the list he was looking for. Perhaps he doesn't know what he was asking because he seems to agree with me?

    Do you get treated as a hostile witness often when you don't answer the question that was asked? You continue to distort the questions or answers in an feeble attempt to to justify your ofbase answers.

    Using any of that equipment from that list on a non-grounded circuit even if fed with GFI protection would be a violation. Using the GFI option to convert other receptacles that are ungrounded would be compliant EXCEPT when used in conjuction with items on that list.

    Sorry, this answer isn't just one of those ones that can be cut and pasted. You need to be able to read and interpret what is being said.


  19. #19
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    26,250

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by Jim Port View Post
    Using any of that equipment from that list on a non-grounded circuit even if fed with GFI protection would be a violation.
    Of current installation requirements, not of the existing installation requirements, which allowed for ungrounded circuits.

    The exception would be, as I've pointed out several times before, when the installation instructions state that it is to be grounded, in which case it is a violation of 110.3(B).

    Michael can clarify what his intent was, he was, at the time of that last post, reporting what he found on a Google search.

    If that was, and is, his intent, then I read his question incorrectly, however, his question did refer to:

    (red text is mine for highlighting)
    Quote Originally Posted by Michael Thomas View Post
    My notes say :

    Some equipment is not allowed to be connected to ungrounded receptacles. Even though all the receptacles have been changed out to grounded type and they are all given GFCI protection, if there is no actual equipment ground conductor connected to the grounded terminal of the receptacle, then a number of cord and plug devices can't use those receptacles.

    I know that (for example) cord connected office equipment such as computers and printers with grounded plunges fall into this category, but I can't find the code reference that defines such equipment.
    This is from a typical GE Refrigerator installation instruction ( http://products.geappliances.com/Mar...e=49-60445.pdf ): (bold and underlining are mine) - this would be a violation of 110.3(B) to plug that into a non-grounded receptacle ... where have I heard 110.3(B) before???
    The power cord of this appliance is equipped with a 3-prong (grounding) plug which mates with a standard 3-prong (grounding) wall outlet to minimize the possibility of electric shock hazard from this appliance.

    Have the wall outlet and circuit checked by a qualified electrician to make sure the outlet is properly grounded.

    If the outlet is a standard 2-prong outlet, it is your personal responsibility and obligation to have it replaced with a properly grounded 3-prong wall outlet.


    The refrigerator should always be plugged into its own individual electrical outlet which has a voltage rating that matches the rating plate.


    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  20. #20
    Join Date
    Aug 2008
    Location
    Maryland
    Posts
    1,899

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by Jerry Peck View Post
    Michael can clarify what his intent was, he was, at the time of that last post, reporting what he found on a Google search.
    What he found using the Google search was the Code Article that I posted.

    BTW, 110.3 is not the answer for everything. It just seems to be your answer when you can't find a more relevant article.


  21. #21
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    26,250

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by Jim Port View Post
    BTW, 110.3 is not the answer for everything. It just seems to be your answer when you can't find a more relevant article.

    No, 110.3(B) is not the answer to everything, and I do not bring it up often, only when needed, such as this thread.

    It really is just as plain and simple as 110.3(B) in cases, such as all the above when the equipment is not installed in accordance with the manufacturer's installation instructions and the listing and labeling.

    Granted, there are times when "another code section can be added on to the violation", but correcting the other code section does not necessarily correct the violation of 110.3(B), meaning there still is a code violation which needs to be corrected.

    Question for you: When you go into a 1930's house wired with ungrounded circuits and find a new(er) refrigerator which is plugged into one of the two-prong adapters, do you write it up as being improperly installed and not grounded? Or how do you write it up? Presuming you are doing a home inspection and not a kitchen remodel code inspection.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  22. #22
    Join Date
    Aug 2008
    Location
    Maryland
    Posts
    1,899

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by Jerry Peck View Post
    No, 110.3(B) is not the answer to everything, and I do not bring it up often, only when needed, such as this thread.

    It really is just as plain and simple as 110.3(B) in cases, such as all the above when the equipment is not installed in accordance with the manufacturer's installation instructions and the listing and labeling.
    Chalk up another answer from Jerry that does answer the question that was asked. Michael cleary asked for a list of equipment that could not be used on ungrounded circuits. He did not ask why it could not be used. 110.3(3) would be WHY it cannot be used and was an inappropriate responce. Jerry your answer is not a list.


  23. #23
    Join Date
    Jul 2008
    Location
    Snowbird (this means I'm retired and migrate between locations), FL/MI
    Posts
    4,086

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by Jim Port View Post
    Michael seems to agree that this is the list he was looking for. Perhaps he doesn't know what he was asking because he seems to agree with me?

    Do you get treated as a hostile witness often when you don't answer the question that was asked? You continue to distort the questions or answers in an feeble attempt to to justify your ofbase answers.

    Sorry, this answer isn't just one of those ones that can be cut and pasted. You need to be able to read and interpret what is being said.
    Well said Jim Port! You gave him an expanded "list" reference, and the defined parameters he asked for are in the reference I provided. The presence of the grounding pin on the cord cap are indicative.

    Last edited by H.G. Watson, Sr.; 02-28-2009 at 10:04 AM.

  24. #24
    Join Date
    Mar 2007
    Location
    Chicago, IL
    Posts
    2,797

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Thanks to all four of you for your responses. All, in their individual ways, are useful, not infrequently the "correct" answer to a question I ask here is the answer to a different question than the one I asked, and the most important thing I learn is something I didn't know I needed to learn when I asked my question!

    This is a business that requires us to be precise in understanding the basis of our understanding, and understanding how to report what we understand...

    Anything that helps improve that understanding is useful.

    I was in fact initially looking for that list of equipment specifically requiring connection to an equipment grounding conductor.

    But I have no problem at all with the discussion expanding to include the general question of how and when lack of such grounding should be reported, and the possible basis for doing so, and I think I have received a "better answer" to my question for it's having done so.

    Last edited by Michael Thomas; 02-28-2009 at 10:25 AM.
    Michael Thomas
    Paragon Property Services Inc., Chicago IL
    http://paragoninspects.com

  25. #25
    Ted Menelly's Avatar
    Ted Menelly Guest

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Hmmm, what a concept. A three prong plug calls for a grounded three prong receptacle.

    What an idea.


    There was a thread about refrigerators going on the same circuit as the kitchen GFCIs when it calls for its own circuit and own little three prong grounded no GFCI receptacle.

    Hmm, another wonderful concept.


  26. #26
    Join Date
    Jul 2008
    Location
    Snowbird (this means I'm retired and migrate between locations), FL/MI
    Posts
    4,086

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Quote Originally Posted by Michael Thomas View Post
    My notes say :


    Some equipment is not allowed to be connected to ungrounded receptacles. Even though all the receptacles have been changed out to grounded type and they are all given GFCI protection, if there is no actual equipment ground conductor connected to the grounded terminal of the receptacle, then a number of cord and plug devices can't use those receptacles.


    I know that (for example) cord connected office equipment such as computers and printers with grounded plunges fall into this category, but I can't find the code reference that defines such equipment.



    Anyone know what it is is?
    It days gone by it was fairly common to have intermittant "grounds" or "floating grounds" attached especially to metalic plumbing as receptacles and wiring was worked on. Although current editions of the NEC prohibit this practice it is something for the HI to be aware of. (also that plumbing work may have replaced the metalic elements breaking this continuous connection to earth and/or ground) with other materials and/or introduced alternate paths - for example replacement of galvanized waste plumbing with PVC, galvanized or copper potable plumbing with pex, CPVC, or other materials, dielectric unions, and removal or losening of jumpers).

    You may find this article of interest Michael Thomas: The 10 Worst Grounding Mistakes You'll Ever Make which amongst other things highlights the "why" about the importance to having cable TV, broadband signal amplifiers and over the air TV amplifiers properly grounded.

    Also as I understand it, in the City of Chicago, and the areas adjacent (Cook County) do not or did not typically run a wire for ECG (3-wire) but use(d) bonded EMT, metalic boxes and self-grounding devices (switches/receptacles) for providing ECG. Something that differs significantly from the usual practices in other areas of the country.


  27. #27
    Join Date
    Jul 2008
    Location
    Snowbird (this means I'm retired and migrate between locations), FL/MI
    Posts
    4,086

    Default Re: Equipment Ground Requirements at Home Office Equipment Receptacles

    Portable appliances with metal cases should have a bonding conductor in the flexible cord and plug to be connected to the distribution system. That is required a separate grounding conductor used to bond (electrically connect) all normally non-current carrying parts of an electrical installation. EGC normally non-current carrying.

    Since around the 60s 120v devices. IIRC since about 96 exception for the 240/with 120 changed and thus the 4-wire appliance cord sets and outlets keeping seperate bond.

    Power supplies and motors that aren't isolated.

    The UL White Book you may still be able to view or DL for free current and prior editions.

    IIRC some high-carbon plastics, cases, switches and the like on some older computer terminals, keyboards, monitors, etc. had some design issues back in the 70s & 80s too (fuse protection in the wrong place) company name started with a "W". Some of the early self contained "portable" CRT & word processors with hard wired keyboards in a metal case can't recall the name at the moment had "pro" at the end and used those early 7 or 10 inch floppy flexable disks were notorious. Wasn't just static charge problems disrupting but high voltage and capacitor discharge conducting and arcing if not properly grounded.

    Last edited by H.G. Watson, Sr.; 03-07-2009 at 09:44 AM.

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •