You're reading an older article from ELECTRICAL CONTRACTOR. Some content, such as code-related information, may be outdated. Visit our homepage to view the most up-to-date articles.
The new type of GFCI employing the latest technology comes with a caveat that must be brought to our attention. Do not get the impression that if this type of receptacle is wired incorrectly that a person cannot be killed or injured.
Although the receptacle will not reset, the outlet is still energized and will not offer any protection. Then, you may ask, how is this different from the existing type of GFCI receptacle?
UL wants Ground-Fault Circuit-Interrupter (GFCI) manufacturers to provide more protection for the internal GFCI circuitry. This has been a particular concern for public safety agencies, including the U.S. Consumer Product Safety Commission (CPSC). However, what will happen when a GFCI is damaged despite its improved resistance to surges and corrosion?
Under the new requirements, the GFCI can still be reset after it is damaged. If, for any reason, the new type is damaged and can no longer provide ground-fault protection, it cannot be reset. This is a GFCI that is fully compliant with the new UL requirements for 2003.
Meeting new UL requirements
Is this new GFCI an improvement? The answer is yes. After many years of discussion, planning, and testing, UL has released the following changes to its standard covering GFCIs.
Six revisions to the UL requirements for the GFCI have been drafted and they became effective January 2003. They are:
1. A more stringent voltage surge test to ensure the GFCI can handle a higher surge current.
2. A new corrosion test to demonstrate greater immunity to moist conditions.
3. A test to verify that proper operation of the GFCI cannot be prevented by manipulation of the GFCI controls.
4. A reverse line-load miswire test that requires the GFCI to trip when miswired.
5. An abnormal overvoltage test that requires the GFCI not become a fire or shock hazard during extreme overvoltage conditions.
6. Increased requirement for GFCI to operate properly after exposure to conducted radio frequencies.
Everyone in the trade must be informed about what it does and does not do. If the new type is miswired:
o The GFCI will not reset
o The GFCI will still be energized
o The GFCI will have no protection
While the GFCI cannot be reset when the receptacle's line and load is reversed, the receptacle is still energized and protection is lost. What then is the difference between the new type and the old in connection with item No. 4? The reset button will not remain pushed in.
Of course, if the electrician or homeowner wires the downstream outlets to the line wires, there is no protection for the downstream receptacles.
If the receptacle is miswired by connecting the hot conductors to the load terminals, and the downstream to the line terminals, these receptacles are also without protection.
If they connect the downstream receptacles to the line terminals of the miswired receptacle, when the power is first turned on, the initial reaction will be the GFCI will trip, and power will be removed from these downstream receptacles. But the GFCI receptacle itself will be hot.
If this sounds confusing, join the crowd. Some of the salesmen I have talked to at both retail and wholesale locations are confused. All those I have contacted had the understanding that with the new type of lockout GFCI receptacle it was impossible for it to be energized if it was miswired.
One salesman told me I had better get hold of the factory rep because he was just there last week and explained that it would not remain energized under such a miswired condition.
A possible solution
I performed tests on several brands and have also talked to UL and the manufacturers. Though it may not state it clearly, most of the instructions warn you of the GFCI not being able to protect if it is miswired.
One manufacturer even gave me the impression that the receptacle would not be energized if it was miswired. I do believe a warning box—in a distinctively different text color than the rest of the instructions—should be on the installation sheet. It should say:
“WARNING: Line/load reversal will leave power on at the GFCI, with no GFCI protection. This miswiring is indicated by the reset button not staying in when pressed.”
Still the responsibility is with the installer, whether it be an electrician, apprentice or homeowner. He or she should be qualified to make the installation.
In the new 2002 NEC, the word “trained” has been added to the definition of “qualified.” Consider this article as your training for this new GFCI. So yes, we have a caveat, and we need the training.
It is noteworthy to mention that I received an e-mail from UL on this subject stating, “We anticipate a new proposal that will require a dead face when a GFCI is wired with line and load reversed. I think that will take care of the problem that you describe.
I will also have to agree with another statement in that e-mail: “What you are asking for is not as simple to design as you might think.” EC
CORCORAN, of EMC Code Consultants, can be reached at 360-757-3605 or via e-mail at [email protected].