2020 NEC Equipment Ground for Ranges and Dryers Receptacle Replacement (Need Clarification)

[Patpowers]

After careful review of the 2020 NEC, I have come to the conclusion that existing branch circuits for ranges and dryers that DO NOT have an Equipment Grounding Conductor (uses the Grounded Conductor for bonding the frame: 3-wire branch circuits); CAN NOT have a receptacle replaced, but MUST BE Fastened in Place or Connected by Permanent Wiring Methods (Fixed), according to 250.134. I come to this conclusion by first reviewing 406.4(D) Replacements of Receptacles.

406.3(B) Ratings: Receptacles and cord connectors shall be rated not less than 15 amperes, 125 volts, or 15 amperes, 250 volts, and shall be of a type not suitable for use as lampholders. MY UNDERSTANDING: THIS INCLUDES RECEPTACLES FOR 30 AMPERES 220 VOLTS AND RECEPTACLES 50 AMPERES 220 VOLTS; COMMON TO DRYERS AND RANGES RESPECTIVELY.


406.4(D) (Replacements) (2) Non–Grounding-Type Receptacles.

(2) Non–Grounding-Type Receptacles.

Where attachment to an equipment grounding conductor does not exist in the receptacle enclosure, the installation shall comply with 406.4(D)(2)(a), (D)(2)(b), or (D)(2)(c).

• (a)
  A non–grounding-type receptacle(s) shall be permitted to be replaced with another non–grounding-type receptacle(s).
  
  Informational Note No. 1:
  Some equipment or appliance manufacturers require that the branch circuit to the equipment or appliance includes an equipment grounding conductor.
  
  Informational Note No. 2:
  See 250.114 for a list of a cord-and-plug-connected equipment or appliances that require an equipment grounding conductor.
  
  
• MY UNDERSTANDING: I HAVE NO REASON TO BELIEVE THAT 406.4(D)2 WOULD NOT APPLY TO A NON-GROUNDING TYPE 3-PRONG DRYER OR RANGE RECEPTACLE. 406.3(B) RATINGS; SEEMS TO VALIDATE MY REASONING. IT WOULD SEEM THAT 406.4(D)(2)(a)A non–grounding-type receptacle(s) shall be permitted to be replaced with another non–grounding-type receptacle(s); SHOULD ALLOW ME TO REPLACE A 3-PRONG RECEPTACLE WITH ANOTHER 3-PRONG RECEPTACLE. HOWEVER, INFORMATIONAL NOTE NO. 2: See 250.114 for a list of a cord-and-plug-connected equipment or appliances that require an equipment grounding conductor; WOULD TELL ME OTHERWISE.
  
  

250.114 Equipment Connected by Cord and Plug.​

Exposed, normally non–current-carrying metal parts of cord-and-plug-connected equipment shall be connected to the equipment grounding conductor under any of the following conditions:
Exception:
Listed tools, listed appliances, and listed equipment covered in 250.114(2) through (4) shall not be required to be connected to an equipment grounding conductor where protected by a system of double insulation or its equivalent. Double insulated equipment shall be distinctively marked.

• 
  
• (3)
  In residential occupancies:
  • a.
    Refrigerators, freezers, and air conditioners
  • b.
    Clothes-washing, clothes-drying, and dish-washing machines; ranges; kitchen waste disposers; information technology equipment; sump pumps; and electrical aquarium equipment
  • c.
    Hand-held motor-operated tools, stationary and fixed motor-operated tools, and 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
    
  Exception: Tools and portable handlamps and portable luminaires likely to be used in wet or conductive locations shall not be required to be connected to an equipment grounding conductor where supplied through an isolating transformer with an ungrounded secondary of not over 50 volts.
  
  
• MY UNDERSTANDING: IF A DRYER OR RANGE IS CONNECTED BY CORD AND PLUG, 250.114 (3) (b); STATES THAT CORD AND PLUG CLOTHES-DRYING AND RANGES MUST BE CONNECTED TO AN EQUIPMENT GROUNDING CONDUCTOR; THERE IS NO EXCEPTION.
  

250.140 Frames of Ranges and Clothes Dryers.

Frames of electric ranges, wall-mounted ovens, counter-mounted cooking units, clothes dryers, and outlet or junction boxes that are part of the circuit for these appliances shall be connected to the equipment grounding conductor in the manner specified by 250.134 or 250.138.
Exception:
For existing branch-circuit installations only where an equipment grounding conductor is not present in the outlet or junction box, the frames of electric ranges, wall-mounted ovens, counter-mounted cooking units, clothes dryers, and outlet or junction boxes that are part of the circuit for these appliances shall be permitted to be connected to the grounded circuit conductor if all the following conditions are met.

• (1)
  The supply circuit is 120/240-volt, single-phase, 3-wire; or 208Y/120-volt derived from a 3-phase, 4-wire, wye-connected system.
• (2)
  The grounded conductor is not smaller than 10 AWG copper or 8 AWG aluminum.
• (3)
  The grounded conductor is insulated, or the grounded conductor is uninsulated and part of a Type SE service-entrance cable and the branch circuit originates at the service equipment.
• (4)
  Grounding contacts of receptacles furnished as part of the equipment are bonded to the equipment.

MY UNDERSTANDING: RANGES AND DRYERS MUST BE CONNECTED SPECIFIED BY 250.134 OR 250.138. HOWEVER THE EXCEPTION STATES THAT WHERE AN EQUIPMENT GROUNDING CONDUCTOR IS NOT PRESENT IN THE OUTLET OR JUNCTION BOX THAT THE FRAME CAN BE BONDED TO THE GROUNDED CONDUCTOR IF THE FOUR CONDITIONS ARE MET. IT DOES NOT SPECIFY RECEPTACLE, WHICH IS NOT THE SAME AS AN OUTLET OR JUNCTION BOX.


250.138 Cord-and-Plug-Connected Equipment.

Non–current-carrying metal parts of cord-and-plug-connected equipment, if required to be connected to an equipment grounding conductor, shall be connected by one of the methods in 250.138(A) or (B).
(A) By Means of an Equipment Grounding Conductor.

By means of an equipment grounding conductor run with the power supply conductors in a cable assembly or flexible cord properly terminated in a grounding-type attachment plug with one fixed grounding contact.
Exception:
The grounding contacting pole of grounding-type plug-in ground-fault circuit interrupters shall be permitted to be of the movable, self-restoring type on circuits operating at not over 150 volts between any two conductors or over 150 volts between any conductor and ground.

(B) By Means of a Separate Flexible Wire or Strap.

By means of a separate flexible wire or strap, insulated or bare, connected to an equipment grounding conductor, and protected as well as practicable against physical damage, where part of equipment.

MY UNDERSTANDING: ONCE AGAIN AS IN 250.114(3)(b) ; 250.138 ALSO OFFERS NO EXCEPTION TO CORD AND PLUG CONNECTED DRYERS AND RANGES
HOWEVER 250.134 DOES REFERENCE USING THE GROUNDED CONDUCTOR FOR THE NON-CURRENT-CARRYING METAL PARTS OF EQUIPMENT.

250.134 Equipment Fastened in Place or Connected by Permanent Wiring Methods (Fixed).

Unless connected to the grounded circuit conductor as permitted by 250.32, 250.140, and 250.142, non–current-carrying metal parts of equipment, raceways, and other enclosures, if grounded, shall be connected to an equipment grounding conductor by one of the following methods:

• (1)
  By connecting to any of the equipment grounding conductors permitted by 250.118(2) through (14)
• (2)
  By connecting to an equipment grounding conductor of the wire type that is contained within the same raceway, contained within the same cable, or otherwise run with the circuit conductors
  Exception No. 1:
  As provided in 250.130(C), the equipment grounding conductor shall be permitted to be run separately from the circuit conductors.
  Exception No. 2:
  For dc circuits, the equipment grounding conductor shall be permitted to be run separately from the circuit conductors
  Informational Note No. 1:
  See 250.102 and 250.168 for equipment bonding jumper requirements.
  Informational Note No. 2:
  See 400.10 for use of flexible cords and flexible cables for fixed equipment.
  

MY CONCLUSION: ACCORDING TO NEC 2020 DRYER AND RANGE RECEPTACLES CAN NOT BE REPLACED WITHOUT ADDING AN EQUIPMENT GROUNDING CONDUCTOR OR YOU MUST WIRE IT ACCORDING TO 250.134 FASTENED IN PLACE OR CONNECTED BY PERMANENT WIRING METHOD (FIXED) AND 250.140 (1-4) MUST APPLY.

PLEASE LET ME KNOW IF I MISSED SOMETHING OR DID I MIS-INTERPRET THE CODE REGARDING THIS MATTER

IS THIS CORRECT???

 

[infinity]

MY UNDERSTANDING: RANGES AND DRYERS MUST BE CONNECTED SPECIFIED BY 250.134 OR 250.138. HOWEVER THE EXCEPTION STATES THAT WHERE AN EQUIPMENT GROUNDING CONDUCTOR IS NOT PRESENT IN THE OUTLET OR JUNCTION BOX THAT THE FRAME CAN BE BONDED TO THE GROUNDED CONDUCTOR IF THE FOUR CONDITIONS ARE MET. IT DOES NOT SPECIFY RECEPTACLE, WHICH IS NOT THE SAME AS AN OUTLET OR JUNCTION BOX.

A 240 volt receptacle is a type of outlet.

Welcome to the Forum.

 

[Patpowers]

Yes, but 250.114 and 250.138 does not allow an exception to equipment grounding conductor for cord and plug dryers or ranges. In order to replace a receptacle 250.140 and 250.134 which states fixed wiring: 250.134 Equipment Fastened in Place or Connected by Permanent Wiring Methods (Fixed). Can you point me to the code article that allows a non-grounding 3-prong receptacle to be replaced with another non-grounding 3-prong receptacle for a cord and plug dryer or range??

 

[Patpowers]

I ask this question because our AHJ are requiring us to change 3-wire conductors for ranges and dryers to 4-wire conductors when we pull permits for sub-panel upgrades. We have several houses with active knob and tubing, and are required to run new conductors to kitchen and laundry rooms, change all receptacles, and use dual function GFCI/CAFCI OCPD’s. Ranges and dryers normally run to the primary panel and would pose minimal risk of objectionable currents when new sub-panels are installed correctly. Our sub-Panels only carry 110v loads.

 

[infinity]

I don't have the book with me but it sounds like the issue is the 3 wire cable from a sub panel not the receptacle.

 

[kwired]

406.4(D)(3) could require GFCI protection in some cases (particularly the dryer which is normally in the laundry area)

AFAIK there is no GFCI receptacles for this kind of thing and you normally would resort to a GFCI breaker for such protection. That protection would be subject to unintended trips if also using the grounded conductor to bond the appliance frame if anything grounded contacts the frame, it should otherwise work as long as there is no other return path created.

I think otherwise the requirement to bring a separate EGC to existing ranges or dryers is specifically covered by 250.140 exception and in many cases is not going to be required.

 

[tortuga]

I don't have the book with me but it sounds like the issue is the 3 wire cable from a sub panel not the receptacle.

Spot on, there is a single exception with 4 conditions to 250.140 for a long time, it is unchanged in 2020, it allows that old neutral to be both a neutral and a EGC. Here the sentence in condition (3):

(3) The grounded conductor is insulated, or the grounded
conductor is uninsulated and part of a Type SE service-
entrance cable and the branch circuit originates at the
service equipment.

I interpret that as you can have:

• A old romex with an insulated neutral and no ECG

OR

• an SE cable that originates in the service

 

[tortuga]

Some people might interpret that as in either case insulated neutral or SE cable, it needs to originate at a service, not a subpanel.

 

[Patpowers]

Spot on, there is a single exception with 4 conditions to 250.140 for a long time, it is unchanged in 2020, it allows that old neutral to be both a neutral and a EGC. Here the sentence in condition (3):



I interpret that as you can have:

• A old romex with an insulated neutral and no ECG

OR

• an SE cable that originates in the service

I understand that, but then it explicitly says that cord and plug range and dryer must have egc. 250.140 allows the outlet and beach circuit, and does not specify receptacle which is part of card and plug. 250,134 fixed wiring does allow the provision of 250.140 but says outlet not receptacle. 250.138 is cord and plug and has no exception to the egc which would be required as to receptacle and plug. My question is where does the code allow for the receptacle to be replaced. Hard-wired or fixed is found in 250.134. That doesn’t cover a receptacle specifically. The specific articles for the receptacle for cord and plug provides no exceptions..

 

[Patpowers]

Spot on, there is a single exception with 4 conditions to 250.140 for a long time, it is unchanged in 2020, it allows that old neutral to be both a neutral and a EGC. Here the sentence in condition (3):



I interpret that as you can have:

• A old romex with an insulated neutral and no ECG

OR

• an SE cable that originates in the service

I understand that, but then it explicitly says that cord and plug range and dryer must have egc. 250.140 allows the outlet and beach circuit, and does not specify receptacle which is part of card and plug. 250,134 fixed wiring does allow the provision of 250.140 but says outlet not receptacle. 250.138 is cord and plug and has no exception to the egc which would be required as to receptacle and plug. My question is where does the code allow for the receptacle to be replaced. Hard-wired or fixed is found in 250.134. That doesn’t cover a receptacle specifically. The specific articles for the receptacle for cord and plug provides no exceptions

 

[tortuga]

A 10-50 or 10-30 receptacle has an EGC, the neutral.

 

[Patpowers]

Spot on, there is a single exception with 4 conditions to 250.140 for a long time, it is unchanged in 2020, it allows that old neutral to be both a neutral and a EGC. Here the sentence in condition (3):



I interpret that as you can have:

• A old romex with an insulated neutral and no ECG

OR

• an SE cable that originates in the service

This will apply to the branch circuit and outlet, our area commonly have a six disconnect 200a main lug on the outside and 100a main panel inside the house. All 220 circuits run to 100a main sub-panel due to knob and tubing.

 

[tortuga]

I ask this question because our AHJ are requiring us to change 3-wire conductors for ranges and dryers to 4-wire conductors when we pull permits for sub-panel upgrades.

Ask the AHJ nicely for a code reference.

All 220 circuits run to 100a main sub-panel due to knob and tubing.

What wiring method is used for the range and dryer? I have never seen knob and tube used for a range or dryer.
All the houses like that around here are either cloth romex, flex or conduit.

 

[Patpowers]

My AHJ allows us to hard wire a range and / or dryer. But they will not allow us to change the receptacle. He says that the code does not allow a cord and plug exception. I cannot find the exception to cord and plug either. I have no problem hard wiring a range that’s already terminated to the primary service to avoid replacing 80ft of conductors. However, most, if not all residential dryers are not listed for hard-wiring. I’m trying to find specific code that does apply to cord and plug range and dryer to avoid having to run new conductors that already comply with 250.140

 

[Patpowers]

Ask the AHJ nicely for a code reference.

What wiring method is used for the range and dryer? I have never seen knob and tube used for a range or dryer.
All the houses like that around here are either cloth romex, flex or conduit.

Knob and tubing only goes to sun-panels, they are not allowed to be modified only to change the panel to accept dual function GFCI/CAFCI OCPD’s. All 220 branch circuits are ran to main service panel, as knob and tubing is not to be used on a 220volt circuit.

 

[Patpowers]

My post should have said all 220v circuits go directly to main service. ( not sub-panel) . Either I’m exhausted or my device autocorrect is acting up.

 

[Patpowers]

My post should have said all 220v circuits go directly to main service. ( not sub-panel) . Either I’m exhausted or my device autocorrect is acting up.

 

[tortuga]

OK, well we use the 250.130(C) method;
Typically I fish a #10 to apprentice under the house or in basement and they hit the water pipe bond.
or on exterior wall I use a foot long 1/4" or so drill bit and run it outside.

 

[wwhitney]

IT DOES NOT SPECIFY RECEPTACLE, WHICH IS NOT THE SAME AS AN OUTLET OR JUNCTION BOX.

Infinity nailed the flaw in the logical chain in post #2. A receptacle occurs in a box which is an outlet. So 250.140 Exception does not exclude receptacles. And as 250.140 references 250.138, the 250.140 Exception is an alternate means of complying with 250.138, which means you have complied with 250.114.

Your AHJ is mistaken.

Cheers, Wayne

 

[don_resqcapt19]

I ask this question because our AHJ are requiring us to change 3-wire conductors for ranges and dryers to 4-wire conductors when we pull permits for sub-panel upgrades. We have several houses with active knob and tubing, and are required to run new conductors to kitchen and laundry rooms, change all receptacles, and use dual function GFCI/CAFCI OCPD’s. Ranges and dryers normally run to the primary panel and would pose minimal risk of objectionable currents when new sub-panels are installed correctly. Our sub-Panels only carry 110v loads.

The use of a 3 wire circuit for ranges and dryers was never permitted for circuits that originated at a sub panel. That was only permitted where teh circuit originated at the service equipment.