Electrical Wiring in the Home/wiring for electric stove
QUESTION: We had new panel installed in our house, inspector failed because electric stove had 3 wires, he wants 4. Our stove is 15 years old with a 3 prong plug, can this stove be changed to a 4 prong, and how difficult is this?
ANSWER: Robert Wilber
Philadelphia Licensed Electrician
Philadelphia License # 3516 - 16765
LIFE SAFETY WARNING! [disclaimer]
Electricity is dangerous!
You can be injured or killed!
Improper installations can cause fire, injury and death!
Are you qualified to do this work?
National Electrical Code definition, NFPA 70 2008 Article 100: Qualified Person. "One who has skills and knowledge related to the construction and operation of the electrical equipment and installations and has received safety training to recognize and avoid the hazards involved."
Electricity is fire in a box! Death on a leash!
Always check with the local “Authority Having Jurisdiction” for an official interpretation before making installation decisions.
In Philadelphia, it is unlawful for anyone except an individual licensed by the City of Philadelphia to install electrical equipment and wiring.
Homeowners are not allowed to install wiring.
The owner of any property wherein any such installation is discovered shall be issued a violation by the Department of Licenses and Inspections.
The limited exceptions include replacing devices and fixtures at existing outlets.
Contact the Department of Licenses and Inspections for more information.
You are more likely to be killed by 120 volts than any other voltage [120 volts creates the PERFECT fatal current through the human body's electrical resistance!]
Ground Fault Circuit Interrupter (GFCI) [downloadable GFI safety pdf]
TURN THE POWER OFF WHEN WORKING!
LIFE SAFETY WARNING! [disclaimer]
This information is provided for the use of parties as they see fit!
I am not responsible for the application of this information by any party, including those lacking sufficient skill or knowledge to perform these steps safely and any hazard created is the SOLE responsibility of the user.
Tell the inspector to read his National Electrical Code:
2002, 2005, 2008, 2011 - Article 250-140 Exception
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
Philadelphia Licensed Electrician answers FAQ
How can I plug a four prong dryer or range into a three prong outlet?
This is one of the most commonly asked questions in FAQ forums about electricity and wiring.
It must be understood that new appliances will be designed to meet the newest standards.
It is not reasonable to expect someone to rewire their home because they need a new dryer or range [stove]!
According to the NEC [National Electrical Code], it is now required to isolate the neutral conductor from the appliance frame or chassis.
It used to be allowable to use the neutral as a grounding means by incorporating a link between the neutral and the chassis.
The problem with this is that, should the neutral become "open" at some point, the chassis or frame then becomes energized!
The answer to this safety issue was to require a separate grounding conductor in the cable feeding the appliance.
The NEC allows the replacement of the new four prong cord with a three prong cord for appliance replacements in existing installations only!
It is then required, when the cord is thusly replaced, to establish the frame grounding link from the chassis to the neutral.
Robert Wilber Electrical Contracting
Philadelphia License # 3516 16765
210.19 (A)(3) Exception 2
---------- FOLLOW-UP ----------
QUESTION: Thank you for you reply. We are from NJ, a licensed electrician installed the new panel and will be doing any other work, not us, as homeowners. Does the local code upstage the state or national codes?
I think you will find, if you inquire aggressively, that the local code is a mere reflection of the adopted NEC, either as referenced in the International Residential Code or directly as an adopted version of the NEC.
Point out Article 250-140 Exception, and ask him to show you the Code stipulating the rejection of this long-standing article. It has existed in some form or other since the decision to isolate the appliance neutral in the 1996 NEC.
You can look up Mike Holt on the web and find endless discussions about this. It is allowed. He is wrong or can show you where this is not allowed where you live. Go to his boss or the State.