dryer 3 prong cord

how to use a 4-prong dryer cord with a 3-slot outlet

how to use a 4-prong dryer cord with a 3-slot outlet

When moving a newer electric dryer into an older house, it's not uncommon to find that the cord and plug included with the new dryer doesn't fit the 240-volt dryer outlet. Before the mid-1990s, most electric clothes dryers operated with three-prong plugs that fit into three-slot outlets, but since 1996, the electric code has required four-slot outlets. The mismatch can work both ways: You may find that a newer dryer doesn't fit an older-style outlet, or that an older clothes dryer doesn't fit a newer outlet.

The change in electric dryer plugs and outlets was made for enhanced safety. In a traditional three-slot 240-volt outlet, there are two hot slots and one neutral slot. These correspond to the two hot and one neutral wire in the three-prong cord. On the dryer, the metal case of the appliance has a ground screw, and this is connected to the neutral wiring terminal of the dryer. In the event of a short to ground, the electrical current is intended to travel on the neutral wire back to the breaker box.

A four-slot outlet has a fourth slot that is dedicated as an equipment grounding conductor. The four-prong cord has a dedicated ground wire that connects to the metal dryer case. The ground and neutral pathways are separate, reducing the change of accidental shock.

If you are faced with the problem of a dryer plug and dryer outlet that don't match, there are two possible remedies. One is to replace the old circuit by installing new four-wire cable and a four-slot outlet, each with a dedicated ground. This is a job for an electrician, and it brings the circuit up to code. The other option is to replace the four-prong cord with a three-prong cord. This is an allowable remedy under the electrical code, which "grandfathers in" older installations. It is only new installations where the four-slot dryer receptacles are required; existing three-slot receptacles are allowed to remain.

Simply replacing the dryer cord is by far the easier solution and the one that most DIYers pursue when they are faced with the problem. However, this configuration is not as safe as a four-wire circuit.

In the main service panel (breaker box), find the double-pole circuit breaker that controls the clothes dryer and flip the breaker to the OFF position. At the dryer outlet, check for power using a non-contact voltage tester.

Unplug the dryer and move it to a location where you have access to the back panel. You may need to disconnect the dryer vent to move and work on the dryer. Make sure you have plenty of light while working.

Most dryer circuits have 30-amp breakers, indicated by a "30" stamped on the switch bar of the breaker. A double-pole breaker is twice as wide as a standard (single-pole) breaker, and most service panels have only a few double-pole breakers.

Use a screwdriver to remove the cover on the electrical connection box on the back of the dryer. It is located just above where the power cord comes out of the dryer and is attached with one or two screws. Set the cover and screws aside.

Remove the strain-relief clamp holding the cord by removing the two screws joining the two halves of the clamp together. Separate the two halves of the fitting and pull them out of the hole individually.

Using a magnetic nut driver or screwdriver, disconnect the black and red cord wires from the left-side and right-side terminals on the dryer's terminal block. These are the hot wire connections. Disconnect the white wire from the center terminal. Disconnect the green grounding wire from the machine case by unscrewing the green grounding screw.

Alternatively, the dryer may have a metal bonding strap (typically connected under the ground screw) instead of a white machine wire. If so, attach the strap to both the ground screw and the neutral (center) terminal.

Thread the loose end of the three-prong cord through the hole in the electrical connection box. Connect the outer two wires (the hot wires) on the cord to the outer two screws terminals, one on each screw. Connect the center wire to the center (neutral) terminal. If there a bonding strap for the ground, it must be connected to the neutral terminal along with the center cord wire.

Slide one half of the strain-relief clamp into the hole under the cord wire. Fit the other half of the clamp in the same way but on the top of the cord. Squeeze the two halves together with pliers and thread the screws into the holes. Tighten the screws until the cord is secure.

Do not re-use the original strain-relief clamp with the new three-prong cord. Clamps for four-prong cords are round and will not properly fit the flat shape of a three-prong cord. Use the strain-relief that comes with the new cord, or buy a compatible clamp separately.

Reattach the connection box cover plate with its screw(s). Slide the dryer into place, and reconnect the dryer vent duct, if necessary. Plug the cord into the outlet. At the main service panel, turn the dryer's circuit breaker back to the ON position, then test the dryer for proper operation.

If you have the related but opposite situationan older dryer with a three-prong cord but a newer house with a four-slot outletit is equally easy to replace an old cord with a new four-prong cord that will fit a four-slot outlet. Most of the steps described above will be the same, with one important difference: The neutral terminal and ground screw will not have a jumper between them, and each will be connected to its own cord wire.

3-prong vs 4-prong dryer outlets: what's the difference? | fred's appliance

3-prong vs 4-prong dryer outlets: what's the difference? | fred's appliance

Most homeowners have run into a problem with trying to hook a 3-prong dryer cord up to a 4-prong outlet, or vice-versa, at one point or another. Whether you move into a new home that has a different outlet or purchase a new dryer with a different power cord, this is an all-too-common scenario. Unfortunately, few people understand the difference between 3-prong and 4-prong dryer cords. In an effort to shed some light on this subject, were going to discuss the purpose of these cords and why theres a growing popularity for 4-prong cables.

Up until the mid-1990s, 3-prong outlets were the standard used in American homes. Nearly all homes built before this time featured either a 3-prong outlet or range outlet (slightly different than a typical 3-prong dryer outlet). It wasnt until 1996 when the National Electrical Code (NEC) was updated to require 4-prong dryer outlets in all new homes. Existing homes may still use 3-prong outlets, as the NEC changes are limited strictly to new homes.

So, why did the NEC make the decision to switch from 3-prong to 4-prong dryer outlets in new homes? Although the old 3-prong outlets were effective at providing power to dryers, they had one major flaw: the ground and neutral wires were grouped together, creating the potential for shock. 3-prong dryer cords contain two hot wires along with a third wire that contained both the ground and neutral wire. If a current happened to make its way onto the ground wire, it could travel up to the dryer.

The more recent 4-prong dryer cords feature two hot wires, a neutral wire and a ground wire. This eliminates the possibility for a ground current traveling to the machine, as it features a separate return path for unused power.

The good news is that you dont have to purchase a new dryer if the current outlet in your home doesnt match. There are a couple of different scenarios ways workarounds, one of which is to purchase a new dryer cord. Most home improvement stores, such as Lowes and Home Depot, sell both 3-prong and 4-prong dryer cables for about $20-$25 bucks. As long as you have access to a Phillips head screwdriver, you can easily change out the dryer cord. Be sure to install the strain relief that comes with the new cord.

changing dryer cords from 4-wire to 3-wire

changing dryer cords from 4-wire to 3-wire

Clothes dryers can be wired with cords that have three prongs as well as with four-prong cords, depending on the age of the wiring installation. Three-prong cordsand 3-slot outletswere once the norm, but since 2008, Article 550.16(A)(2) of the National Electrical Code (NEC) has stipulated that connections for electric clothes dryers must be made with a4-conductor cordand 3-pole, 4-wire,grounding-type plugs or by Type AC cable. This is the requirement for new construction or when a new clothes dryer circuit is installed, but older installations are allowed to retain their 3-prong, 3-slot dryer cord and outlet configurations.

It is, therefore, somewhat rare that you would want to change a 4-prong cord on an electric dryer to a 3-prong cord. It is much more common to go the other directionto update by changing your dryer cord from 3-prongs to 4-prongs in order to meet the current code requirements. However, if you have moved into a new house or apartment that has a 3-slot dryer outlet, then you might want to change out your 4-prong cord with a 4-prong in order to make use of that existing outlet. It is entirely allowable to do this.

Related Equipments