On a Dryer ckt repair I found the 1 hot leg shorted to ground (to the ground wire only), causing the breaker to trip. It was a 10-4 romex so I swapped the neutral with the shorted hot leg and ID'd them so. It worked fine, but now the ground wire and the new neutral were shorted together somewhere in the run. On the dryer recept I left the ground wire where it should be and put the new neutral in the neutral lug where it should be. In thoery this should be fine. There are 2 hot legs, a neutral, and a ground, wired in the correct lugs in the recept. The only difference is the neutral and ground wire are shorted together somewhere in the romex, but.. they are tied together in the main panel anyway. Even though this is probably fine, I recommended running a new 30a dryer circuit. Any Opinions on this?
The Golden Rule - "The man with the gold makes the rule"
Apart from any consideration of the short, another problem with a situation such as this is that there may be other damage to the cable.
If the (originally) hot-ground short was caused by a mangled cable somewhere, then there may well be other damage, e.g. a hot conductor chewed up reducing its CSA at that point and therefore creating a hot spot under load.
aldav53, This was taken from another post made by sparky:
250.140 Frames of Ranges and Clothes Dryers. This section shall apply to existing branch-circuit installations only. New branch-circuit installations shall comply with 250.134 and 250.138. 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 grounded in the manner specified by 250.134 or 250.138; or, except for mobile homes and recreational vehicles, shall be permitted to be grounded 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.
this is the 'commentary' after it..
Section 250.140(4) applies only to existing branch circuits supplying the appliances specified in this section. The grounded conductor (neutral) is no longer allowed to be used for grounding the metal non–current-carrying parts of the appliances listed in 250.140. Branch circuits installed for new appliance installations are required to provide an equipment grounding conductor for grounding the non-current-carrying parts. Caution should be exercised to ensure that new appliances connected to an existing branch circuit are properly grounded. An older appliance connected to a new branch circuit must have its 3-wire cord and plug replaced with a 4-conductor cord, with one of those conductors being an equipment grounding conductor. The bonding jumper between the neutral and the frame of the appliance must be removed. If a new appliance is connected to an existing branch circuit without an equipment grounding conductor, where the neutral conductor was previously used for grounding the appliance, a bonding jumper must be installed at the appliance terminal to connect the frame to the neutral. The grounded circuit conductor of an existing branch circuit is still permitted to be used to ground the frame of an electric range, wall-mounted oven, or counter-mounted cooking unit, provided all four conditions of 250.140 are met. The grounded circuit conductor is also permitted to be used to ground any junction boxes in the circuit supplying the appliance, and a 3-wire pigtail and range receptacle is permitted to be used, even though the circuit to the receptacle contains a separate equipment grounding conductor. Where service-entrance cable was previously installed, an uninsulated covered neutral conductor was allowed. However, the circuit was required to originate at the service equipment to avoid neutral current from downstream panelboards flowing on metal objects, such as pipes or ducts. Exhibit 250.51 shows an existing installation in which Type SE service-entrance cable was used for ranges, dryers, wall-mounted ovens, and counter-mounted cooking units. Junction boxes in the supply circuit were also permitted to be grounded from the grounded neutral conductor
Aldav53. Why would you want to expose yourself to the liability of this type of repair, even on a temporary basis. One of my journeyman electricans did this same type of repair on a service call last summer,without calling the office first to get the O.K. He told the tentent that he would be back the next day with the material he needed to fix it right. The landlord will not allow us to come back and complete the repair properly,does not want to pay for additional service call. I have called the AHJ and fire marshall to explain the problem and I am still sweating this mistake.
Re: Dryer Ckt - Repair#20219 01/13/0312:14 AM01/13/0312:14 AM