NFPA - TIA 1748 & TIA 1749

[mtnelect]

1. Add a new Exception No. 5 to section 210.8(A) to read as follows:
210.8(A) Dwelling Units.
…
Exception No. 5: GFCI protection shall not be required for a receptacle serving a refrigerator
or HVAC appliance if all of the following conditions are met:
(1) The appliance is located within a dedicated space.
(2) The appliance is on an individual branch circuit.
(3) In normal use, the appliance is not easily moved or is fastened in place.
This exception shall expire January 1, 2028.

 

[Fred B]

is this tia approved or pending?

 

[don_resqcapt19]

is this tia approved or pending?

out for public comment...will take a few months to find out if it passes.
If you are using Link, it will show up a few days after it is issued

 

[fishin' electrician]

First future inception dates and now expiration dates? I'm done with their silliness, this document is becoming a joke.

 

[brantmacga]

First future inception dates and now expiration dates? I'm done with their silliness, this document is becoming a joke.

I believe the expiration date is to give manufacturer's time to work out the nuisance tripping on new appliances. Georgia already has an amendment to delete the requirement for HVAC equipment from the 2020 NEC. My local AHJ doesn't require GFCI on refrigerators in a dwelling.

 

[don_resqcapt19]

I believe the expiration date is to give manufacturer's time to work out the nuisance tripping on new appliances. Georgia already has an amendment to delete the requirement for HVAC equipment from the 2020 NEC. My local AHJ doesn't require GFCI on refrigerators in a dwelling.

I really think it is UL 943 that needs to work out the problems associated with high frequency leakage current from the new equipment that used various types of drives.
While the proposed TIA mentioned a proposal in front of UL 943, I am on the UL technical committee for 943 and no such proposal is on the docket at this time.

 

[don_resqcapt19]

There are three task groups working within 943 for now product standards to help with the high frequency leakage current that is causing some GFCIs to trip. They all have to complete their work and turn that work into proposals for the UL 943 technical committee to review and vote on. The process takes time.

The task group for high frequency immunity for the GFCI device is close to submitting a proposal to the technical committee.
It is interesting that there is a wide variation with GFCIs from some manufacturers being pretty much immune to the high frequency leakage currents right now. It is also interesting that the amount of leakage current before the GFCI will be required to trip will go up as the frequency goes up as the higher frequency leakage current does not pose the same hazard to people as 60 hertz does.

I expect a completed and published standard is a couple of years away.

 

[fishin' electrician]

I believe the expiration date is to give manufacturer's time to work out the nuisance tripping on new appliances. Georgia already has an amendment to delete the requirement for HVAC equipment from the 2020 NEC. My local AHJ doesn't require GFCI on refrigerators in a dwelling.

Then it shouldn't be in a Code Standard. Something isn't only safe until a certain date.

 

[don_resqcapt19]

Then it shouldn't be in a Code Standard. Something isn't only safe until a certain date.

While UL 943 is working towards a solution as are appliance manufacturers, future dates in the code are often used to make sure progress is being made towards a solution. Where there is already a solution, then the date is use to drive manufacturers to build their products to meet the solution.

There is an issue with GFCIs as all of the design and testing is only based on 60 hertz. The use of power conversion equipment (VFDs) to meet energy standards sometimes results in high frequency leakage currents that cause some GFCIs to trip at levels of leakage tha are considered to be safe.
Given that the UL 943 solution will require the re-engineering of the GFCIs, it would be a big surprise to me if there are GFCI products available by that date. It also appears that 943 may permit two types of GFCIs,, the one we have now and a new one that has immunity to high frequency currents. If that is the case, the problem will still exist unless the NEC requires the use of the proposed GDCI-HF devices. It would be my guess that the GFCI-HFs will cost more, so unless the code requires them to be used the standard ones will continue to be used and we will still have the problem of equipment that has power conversion equipment causing unnecessary GFCI trips.