GFI Protection for hard-wired ranges.

N

npavicic

Member
Location
Westland, Michigan
Occupation
Electrical Inspector
210-8 (d) lists electric ranges that require GFI protection. Does this apply to dwelling units? I ask this because it states other than dwelling units. If the range is hardwired do we still provide GFI protection?
 
Section (A) applies only to dwelling units, section (B) applies only to other than dwelling units, section (D) applies to both dwelling and non-dwelling. The unamended NEC requires GFCI protection for all ranges everywhere, including hardwired.

If you have any way not to enforce GFCI protection on ranges, it is wise to do so. Many common ranges nuisance trip the GFCIs so much that people can't use their range at all. I have spent several years digging into it and it is not a problem that is fixable by the electrician. I don't expect it to get better for another 3 years at least.

There are extensive threads on this subject on this forum (https://forums.mikeholt.com/threads/range-tripping-gfci-210-8-555-53.2582546/), and I have collected a whole bunch of white papers and reports and expert opinions on the subject that I would be willing to send you if you DM me. That provision has been amended out of several state codes and we amend it out locally as well.
 
npavicic said:
210-8 (d) lists electric ranges that require GFI protection. Does this apply to dwelling units? I ask this because it states other than dwelling units. If the range is hardwired do we still provide GFI protection?
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The way I read 210.8(D) you would need gfci protection for both hardwired and cord and plug
 
NEC Inspector said:
Section (A) applies only to dwelling units, section (B) applies only to other than dwelling units, section (D) applies to both dwelling and non-dwelling. The unamended NEC requires GFCI protection for all ranges everywhere, including hardwired.

If you have any way not to enforce GFCI protection on ranges, it is wise to do so. Many common ranges nuisance trip the GFCIs so much that people can't use their range at all. I have spent several years digging into it and it is not a problem that is fixable by the electrician. I don't expect it to get better for another 3 years at least.

There are extensive threads on this subject on this forum (https://forums.mikeholt.com/threads/range-tripping-gfci-210-8-555-53.2582546/), and I have collected a whole bunch of white papers and reports and expert opinions on the subject that I would be willing to send you if you DM me. That provision has been amended out of several state codes and we amend it out locally as well.
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Have you found there to be similar problems with clothes dryers?

Is there one thing in particular with a range that’s problematic?
 
Most GFCI tripping of ranges has been from a manufacturing issue related to the calrod heating elements. If these are not completely dried out in the manufacturing process, there will be enough leakage current to trip a GFCI. In most case this problem can be solved by using a conventional breaker and running all of the elements on high for 20 to 30 minutes. This will dry the calrod elements and then you can use the code required GFCI breaker.
 
nizak said:
Have you found there to be similar problems with clothes dryers?

Is there one thing in particular with a range that’s problematic?
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In the language, how does section D apply to both dwelling and non-dwelling? I am not seeing this. I don't find it expressed. Thank you so much for the feedback.
 
npavicic said:
In the language, how does section D apply to both dwelling and non-dwelling? I am not seeing this. I don't find it expressed. Thank you so much for the feedback.
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Article 210.8 is broken into sections (A)-(F). Each section stands on it's own - the requirements in (D) are separate from the ones in (A) and (B) and only relate to the general portion of 210.8 that is written before 210.8 is divided into sections (A)-(F). Section (A) specifically says that it applies only to dwelling units, and Section (B) says it only applies to non-dwellings. Section (D) does not limit itself at all, and since it stands alone as only modified by the general language at the beginning of 210.8, the requirements of (D) apply to all occupancies, not just dwelling or non-dwelling
nizak said:
Have you found there to be similar problems with clothes dryers? Is there one thing in particular with a range that’s problematic?
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The complaints I get locally are almost all on air conditioners and ranges. I have only had one dryer complaint. I don't know why.
 
This is one of the studies that I found interesting about the trip levels of GFCI's. Appliance manufacturer's use variable frequency drives now in order to meet federal efficiency guidelines, and the high frequency leakage current trips GFCI's because they were never really designed to have to deal with anything other than 60hz. Interestingly, higher frequency current has a higher let-go threshold than 60hz, so you could trip a GFCI at higher than 5 milliamps on high-frequency current and have equivalent safety.

GFCI's need to be updated just as much as the appliances do.
 

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Eddie702 said:
If that is the case and the ranges are not able to be GFCI protected when new then the MFGs are supplying a non compliant product. Maybe the heating elements should be dried out at the factory.

I wouldn't buy a car I couldn't drive
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There is nothing in the range product standard that sets a maximum 5mA leakage current, so the products are compliant.
 
NEC Inspector said:
This is one of the studies that I found interesting about the trip levels of GFCI's. Appliance manufacturer's use variable frequency drives now in order to meet federal efficiency guidelines, and the high frequency leakage current trips GFCI's because they were never really designed to have to deal with anything other than 60hz. Interestingly, higher frequency current has a higher let-go threshold than 60hz, so you could trip a GFCI at higher than 5 milliamps on high-frequency current and have equivalent safety.

GFCI's need to be updated just as much as the appliances do.
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UL 943 is working on changes to the product standard to permit (I would prefer require) a GFCI-HF. The standard is not complete yet, but part of it is based on what you stated.
However the process to change a product standard takes at least as long as the process to change a code rule.
 
Eddie702 said:
If that is the case and the ranges are not able to be GFCI protected when new then the MFGs are supplying a non compliant product. Maybe the heating elements should be dried out at the factory.

I wouldn't buy a car I couldn't drive
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Would you buy a car that you had to 'break in' before you drove it normally?
 
@npavicic it says your an electrical inspector, so in that case what I would do is check in with your state or local department head and have a meeting about it. I am not sure how codes are adopted in your state, but I would propose at minimum amend the 240V GFCI requirements to accept a '30ma GFPE breaker' or even delete the requirement entirely.
 
don_resqcapt19 said:
Most GFCI tripping of ranges has been from a manufacturing issue related to the calrod heating elements. If these are not completely dried out in the manufacturing process, there will be enough leakage current to trip a GFCI. In most case this problem can be solved by using a conventional breaker and running all of the elements on high for 20 to 30 minutes. This will dry the calrod elements and then you can use the code required GFCI breaker.
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I tried doing this on one of 30 ranges in an apartment building but probably only had it on for 15 mins. I thought it may have worked but I decided F this, no one is paying us or will pay us to do this so we let people move in and wait. And the tenant complaints started and owner paid to replace all the $90 CBs for $17 regular breakers. These "smart" people that write these code requirements without manufacturers input are ... .
 
farmantenna said:
These "smart" people that write these code requirements without manufacturers input are ... .
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I'd bet there was manufacturers input on the code requirements but from the GFCI manufacturers and not the appliance manufacturers.

They been on a mission for a long time to get GFCI and AFCI on as much as possible, it helps the bottom line. We will work out the side effects as they show up and let the consumers and installers eat some the costs we would have had to put into R&D to get a more suitable product before pushing it to code making panels.

GFCI's were mostly a good thing from the start. But until more recent years they haven't hardly needed to be able to work on loads with high frequency leakage. But they also been pushing them for areas they maybe aren't all that necessary. Outside of old range/dryer circuits that were allowed to bond the appliance frame to the grounded conductor that could easily have some GFCI issues if used there how often has anyone ran into a compromised EGC on such appliance, cord connected or hard wired? (Not counting ignorance by the installer). It just doesn't happen all that easily without something rather intentional going on.
 
farmantenna said:
These "smart" people that write these code requirements without manufacturers input are ... .
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There was another poster on here that had found all the ranges in a mulit unit building still had the neutral and ground bonded even though the appliance supplier had installed a 4-wire cord.
The NFPA and CMP should have first deleted 250.140(B) (or the exception in older codes that allows a neutral to bond the range) and coerce residential range and dryer appliance manufactures to migrate to a NEMA '6' 240V type cords such as a 6-50 for ranges or a 6-30 for dryers,
There is too much confusion and possibility of error with 10-50 and 14-50, and appliance installers often are not highly trained.

I recently was troubleshooting a brand new dryer that had been delivered with a 4-wire cord and had the neutral and frame still bonded, it was un related to the issue at hand but I noticed it, and it was not easy to spot.
1751646337651.png

I'd also delete 210.6(A)(2) and allow Cord-and-plug-connected loads 1440 volt-amperes or less to be 240V.
 
kwired said:
I'd bet there was manufacturers input on the code requirements but from the GFCI manufacturers and not the appliance manufacturers.

They been on a mission for a long time to get GFCI and AFCI on as much as possible, it helps the bottom line. We will work out the side effects as they show up and let the consumers and installers eat some the costs we would have had to put into R&D to get a more suitable product before pushing it to code making panels.

GFCI's were mostly a good thing from the start. But until more recent years they haven't hardly needed to be able to work on loads with high frequency leakage. But they also been pushing them for areas they maybe aren't all that necessary. Outside of old range/dryer circuits that were allowed to bond the appliance frame to the grounded conductor that could easily have some GFCI issues if used there how often has anyone ran into a compromised EGC on such appliance, cord connected or hard wired? (Not counting ignorance by the installer). It just doesn't happen all that easily without something rather intentional going on.
Click to expand...
There is at least one person from the appliance industry on CMP 2. Not sure if that person raised objections or not.
 
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