Upgrading dryer and range 240 volt circuits

[davedevito]

Just wondering what the code article is that states the 3 wire range and dryer circuits have to be upgraded to a 4 wire code compliant circuit if a 4 wire SER is run to a main panel from the meter main outside?

 

[roger]

Read through 250.140 and pay attention to the exceptions.

 

[Little Bill]

Just wondering what the code article is that states the 3 wire range and dryer circuits have to be upgraded to a 4 wire code compliant circuit if a 4 wire SER is run to a main panel from the meter main outside?

Are you saying that there used to be only a regular meter, and main panel inside, and now a meter-main has been installed and a new 4-wire cable has been run to the inside panel, making it a subpanel?

 

[don_resqcapt19]

They added language in 250.140 to address this issue and to permit the existing 3 wire range or dryer circuit to remain when the location of the service equipment has change resulting in the range or dryer circuit originating in a panel other than the service equipment.
Prior to the 2023 code, it would require that you change the existing 3 wire circuit to a 4 wire circuit, unless your AHJ says other wise.

 

[shortcircuit2]

They added language in 250.140 to address this issue and to permit the existing 3 wire range or dryer circuit to remain when the location of the service equipment has change resulting in the range or dryer circuit originating in a panel other than the service equipment.
Prior to the 2023 code, it would require that you change the existing 3 wire circuit to a 4 wire circuit, unless your AHJ says other wise.

Fortunately for Massachusetts persons and property, the language in 250.140(B)(5) is deleted through our 2023 amendments and the NEC “band-aid” is not an option. The 3-wire branch circuit feeding ranges and dryers is a hazard. The biggest issue is unqualified appliance delivery personnel installing the cord incorrectly on the newly purchased appliance.

Now when those branch circuits are replaced under the 2023 Code, they will be installed with 4-wire and also have GFCI in all circumstances because ranges and dryers are required to have such protection per 210.8(D)…at least in Massachusetts.

 

[alexfox1986]

Just wondering what the code article is that states the 3 wire range and dryer circuits have to be upgraded to a 4 wire code compliant circuit if a 4 wire SER is run to a main panel from the meter main outside?

Hi!

The requirement to upgrade a 3-wire range or dryer circuit to a 4-wire circuit when a 4-wire service-entrance conductor is installed is specified in section 250.140 of the National Electrical Code (NEC). Specifically, section 250.140 of the 2020 NEC states:

"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."

This means that when a new 4-wire service-entrance conductor is installed, any existing 3-wire circuits for ranges and dryers must be upgraded to a 4-wire circuit with a separate equipment grounding conductor. This is necessary to ensure that the frame of the appliance is properly grounded, which is important for safety reasons.

It's worth noting that different editions of the NEC may have slightly different language or requirements, so it's always a good idea to consult the specific version of the code that applies to your installation. Additionally, local code amendments may also apply, so it's important to check with the local authority having jurisdiction (AHJ) to determine the specific requirements for your area.

 

[rc/retired]

Hi

This means that when a new 4-wire service-entrance conductor is installed, any existing 3-wire circuits for ranges and dryers must be upgraded to a 4-wire circuit with a separate equipment grounding conductor. This is necessary to ensure that the frame of the appliance is properly grounded, which is important for safety reasons.

I don't believe that is true. Read the exception.
If every time any code is changed and we must comply, nobody can afford to live anywhere! JMHO

Ron

 

[don_resqcapt19]

I don't believe that is true. Read the exception.
If every time any code is changed and we must comply, nobody can afford to live anywhere! JMHO

Ron

The issue is item (3) in the exception. If you make change that results in the source for the range or dryer circuit no longer being in the service equipment, you have to upgrade those circuits. That is why they made the change in the 2023 code that I mentioned in post #4.

 

[mtnelect]

This might help to explain.