Gfci TIA for Ranges

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Dennis Alwon

Dennis Alwon

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It looks like they over looked an issue with making ranges 240V gfci protected. This tia is up for vote

NFPA 70®-2020 Edition National Electrical Code® TIA Log No.: 1563 Reference: 210.8(A)(7) Exception (new) Comment Closing Date: April 28, 2021 Submitter: Matt Williams/Randy Cooper, Association of Home Appliance Manufacturers www.nfpa.org/70 1. Revise Section 210.8(A)(7) to read as follows: 210.8 Ground-Fault Circuit-Interrupter Protection for Personnel. … (A) Dwelling Units. … (7) Sinks – where receptacles are installed within 1.8 m (6 ft) from the top inside edge of the bowl of the sink.

Exception to (7): This requirement shall become effective January 1, 2023, for cooking range receptacles rated 30 amperes through 50 amperes that are supplied by single-phase branch circuits rated 150 volts or less to ground.

Substantiation: While this expanded GFCI protection for greater than 125 volt receptacles is in the 2020 NEC, standards for cooking range products connected to these outlets have not been harmonized with this protection (UL 858). The 210.8(A)(7) language creates a product requirement that is beyond the listing requirement in UL 858, this has created tripping. Until the UL product standard is harmonized, designers, installers, AHJs, and consumers are forced to choose between a compliant installation and an operational installation. The purpose of this proposed TIA is not to eliminate the GFCI protection but just postpone the effectivity of the higher voltage range receptacles. This will provide time for the NEC, product standards, and product certification to be harmonized. This non-compatibility is currently being addressed in UL processes. AHAM is working to submit a proposal to UL 858 to add leakage current requirements for 240 volt products. However, since this requirement did not exist previously, there are significant technical issues that need to be resolved prior to submission of the proposal. It will take time to align the standards and certify new products to those new standards so the requirement effectivity date of 2023 is appropriate. The precipitating event that drove the extension of GFCI’s was linked to a recalled product. However, a GFCI would have tripped on this product due to the missing grounding strap screw. Since this was a recalled product, it should not be considered representative of the millions of ranges produced each year that are compliant to the UL 858 standard in regards to grounding with a solid 4-wire connection. Section 90.4 allows jurisdictions to approve the use of products, constructions, or materials that comply with the most recent previous edition of this Code (2017). This TIA is meant to formalize such allowances so that individual AHJ approval is not needed.
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There was a previous TIA submitted for this same issue with a different substantiation and it failed. It was broader in nature and maybe this one limiting to cooking equipment will be accepted. The previous language is below.
Exception to (7): For receptacles rated 30 through 50 amperes that are supplied by single phase branch circuits rated 150 volts to ground or less, this requirement shall become effective January 1, 2023.
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The substantiation indicates that there are tripping problems with electric ranges and ovens. The leakage current when the elements are being brought up to operating temperature on its initial operation. This leakage current is caused by moisture in the element and can result in leakage current in the 6 to 8 mA range for 4 to 6 minutes. This is causing the GFCI device to open the circuit. Resetting the GFCI device 6 to 10, or even more, times on the initial operation of the equipment will create enough heat to drive the moisture out of the heating elements. The tripping does not re-occur after the initial operation. (I expect that since most of this equipment is foreign made, moisture enters on the long ocean voyage, and that the issue might re-occur if the equipment is not used for a long period of time)
 
Heck we still have some pool manufacturers that require a specific brand gfci for their pool pumps. That doesn't make any sense....They need to redesign those darn things.
 
While not official, the meeting vote at the CMP 2 first draft meeting accepted a PI to require all dwelling unit receptacles to have GFCI protection. The vote at the meeting had more than the required 2/3s majority. The official ballot action will be published on 7/2.
 
I think, as in the a/c unit, it is to avoid a situation where an equipment grounding conductor got loose or was installed incorrectly.
 
Dennis Alwon said:
I think, as in the a/c unit, it is to avoid a situation where an equipment grounding conductor got loose or was installed incorrectly.
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yeah, it’s like the requirement of sign disconnects breaking the neutral too, sign guys who were not qualified, were wiring them wrong causing injuries and fatalities, prompting that change.
 
Little Bill said:
What is the substantiation for needing GFCI on a stove in the first place? I've never heard of a problem with a properly wired stove/range shocking people and they've been around for 70+ years.
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There was a paragraph in the TIA that said the GFCI rule was added based on an issue with a particular range that was recalled due to an issue with the bonding strap. Went on to say that one faulty product shouldn’t be a basis for a code change.


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The precipitating event that drove the extension of GFCI’s was linked to a recalled product.
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This POs me so much. The internal quality of appliances has nose dived to the point end of life failure modes are marked by fire or shock yet the NEC is called upon as being the solution by code making panel members working for the same companies that produce the trash of concern.
 
don_resqcapt19 said:
There was a previous TIA submitted for this same issue with a different substantiation and it failed. It was broader in nature and maybe this one limiting to cooking equipment will be accepted. The previous language is below.


The substantiation indicates that there are tripping problems with electric ranges and ovens. The leakage current when the elements are being brought up to operating temperature on its initial operation. This leakage current is caused by moisture in the element and can result in leakage current in the 6 to 8 mA range for 4 to 6 minutes. This is causing the GFCI device to open the circuit. Resetting the GFCI device 6 to 10, or even more, times on the initial operation of the equipment will create enough heat to drive the moisture out of the heating elements. The tripping does not re-occur after the initial operation. (I expect that since most of this equipment is foreign made, moisture enters on the long ocean voyage, and that the issue might re-occur if the equipment is not used for a long period of time)
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Still won't guarantee 100% nuisance free operation. Capacitive coupling between every energized part and its sheath, frame, chassis, ect is physically unavoidable.
 
Any idea when this goes to a vote? And also for the hvac gfci amendment?


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I still think there is no good reason for GFCI on hard wired (other than maybe 680 applications) items and on cord and plug connected items that utilize something other than 5-15/20 or 6-15/20 configurations.

Anybody ever seen a missing EGC pin on a 30-50 amp receptacle, or on locking type receptacles of any rating?

The incident(s) that prompted the AC units to be protected were already in violation of other code sections.

You know how they fixed GFCI tripping issues with some laundry appliances (particularly with electronic drive systems that don't play well with GFCI's)?

Last time I looked you won't find a lot on the internet, but they have "grounding relays/switches" inside them. The outer frame is connected to the EGC, but the motor frame is isolated. Motor frame has a grounding wire but is only connected if you take the access cover off to service it. The one I first had experience with was tripping GFCI receptacle. I didn't want customer to call appliance guy, as I just knew they would likely be telling us this can't be on a GFCI or that the GFCI must be defective. So I was going to try to figure out if it was something obvious first.

I tested for ground faults on cord cap with basic DVM - no fail. I plugged the washer into a two prong to three prong cheater - GFCI would hold. Always filled with water but tripped GFCI immediately when trying to start turning the drum (front load washer) so I determined it probably was something with the drive not playing well with GFCI's. I did take back cover off the machine hoping to find something obvious. I did find a device with green wires attached to it down low on the frame and up against back cover. It had broken mounting tab and was hanging free. After figuring out exactly what this does - it is like the door switch on furnaces, take the cover off and it actuates the switch - closing the EGC to the motor frame, and that doesn't play well with GFCI's. They must want it grounded if a service person has the cover off though, otherwise why even bother grounding something isolated and inaccessible in general use situation? I unplugged the wire to the motor frame and it worked until I could get a replacement for the broken one. Parts catalog called it a grounding switch or grounding relay or something of that nature.
 
kwired said:
I still think there is no good reason for GFCI on hard wired (other than maybe 680 applications) items and on cord and plug connected items that utilize something other than 5-15/20 or 6-15/20 configurations.

Anybody ever seen a missing EGC pin on a 30-50 amp receptacle, or on locking type receptacles of any rating?

The incident(s) that prompted the AC units to be protected were already in violation of other code sections.

You know how they fixed GFCI tripping issues with some laundry appliances (particularly with electronic drive systems that don't play well with GFCI's)?

Last time I looked you won't find a lot on the internet, but they have "grounding relays/switches" inside them. The outer frame is connected to the EGC, but the motor frame is isolated. Motor frame has a grounding wire but is only connected if you take the access cover off to service it. The one I first had experience with was tripping GFCI receptacle. I didn't want customer to call appliance guy, as I just knew they would likely be telling us this can't be on a GFCI or that the GFCI must be defective. So I was going to try to figure out if it was something obvious first.

I tested for ground faults on cord cap with basic DVM - no fail. I plugged the washer into a two prong to three prong cheater - GFCI would hold. Always filled with water but tripped GFCI immediately when trying to start turning the drum (front load washer) so I determined it probably was something with the drive not playing well with GFCI's. I did take back cover off the machine hoping to find something obvious. I did find a device with green wires attached to it down low on the frame and up against back cover. It had broken mounting tab and was hanging free. After figuring out exactly what this does - it is like the door switch on furnaces, take the cover off and it actuates the switch - closing the EGC to the motor frame, and that doesn't play well with GFCI's. They must want it grounded if a service person has the cover off though, otherwise why even bother grounding something isolated and inaccessible in general use situation? I unplugged the wire to the motor frame and it worked until I could get a replacement for the broken one. Parts catalog called it a grounding switch or grounding relay or something of that nature.
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Bingo! Thank you bringing up those ground switches! :) I thought no one would. Until the CMPs learn electrical theory, it will only get worse if not more dangerous.

Again, for our code members:



1620489997338.png
 
kwired said:
I still think there is no good reason for GFCI on hard wired (other than maybe 680 applications) items and on cord and plug connected items that utilize something other than 5-15/20 or 6-15/20 configurations.
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I'm going to go out and say that the NEMA 5-15/20 and 6-15/20 designs are fundamentally flawed and were technically never supposed to become dominant. The original Hubbell receptacle had grounding provisions since day one, and treated the ground contacts with the same integrity as the current carrying contacts. I won't shed a tear when the NEMA designs are finally gone.
 
brantmacga said:
Any idea when this goes to a vote? And also for the hvac gfci amendment?

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You can go to nfpa.org/70, select the "next edition" tap and scroll down to Code Making Panel 2 under the "other committee information" heading. Note that is the second appearance of the Code Making Panel 2 heading. The first appearance is information related to the first draft of the 2023 code.

The proposed TIAs that you are asking about are TIAs 1563 and 1564. It appears that the process is not yet complete.
 
mikeames said:
As per Dons Instructions:

No 1563 or 1564 as he stated.
View attachment 2556532

1529 is the split AC unit TIA
1535 is the Lighting outlets on stairs (210.70(A)(2) related to dimmers and full control
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IMHO, manufacturers are likely to isolate all working metal components of ranges, dryers, AC, ect (besides the user contactable skin) from ground as has been happening with dishwashers and washing machines since the 90s.

For example, this dishwasher tech sheet:


https://imgur.com/WfWToAI

IMO, isolating energized parts from ground increases the probability of fire in that a failed component will remain energized vs short to the stator or armature tripping a breaker.

As an example, a melted (over-heated) drain solenoid:

https://appliantology.smugmug.com/Appliantology/Drain-Solenoid-Meltdown-in-a/

Asking that major appliances be on a 5ma GFCI is IMO unreasonable; Leakage current and capacitive coupling is impossible to avoid without isolating components from ground.
 
What makes you think those components are isolated from ground? The solenoid in your picture has a metal mounting plate that gets mounted to the metal frame of the dishwasher. An overheating solenoid will eventually create a ground fault tripping a GFCI breaker. It will probably never pull enough current to trip a standard breaker.

While I don't agree with some of the new requirements for GFCI protection, especially central A/C equipment, in most case there will not be any issues other than the cost of the GFCI.

I have not had any call backs on projects we have wired due to dishwashers and disposals tripping GFCI's.

Commercial kitchens have required GFCI protection for a long time now without major issues.
 
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