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An appliance with a polarized power cord has a NEMA 1-15P plug with prongs that match the outlet. A grounded NEMA 1-15P has three prongs. It’s polarized because it can only go into the receptacle in one direction. The blades don’t have to be different sizes, but they are on some three-prong plugs anyway.
What does a polarized extension cord mean?
To prevent shocks from the metal parts of a light, lamp cords and two-wire extension cords are always polarized. This means the plug has a small blade for the hot wire and a wide blade for the neutral wire, and the wires feeding those blades should not be reversed when you put a new plug on.
What is the purpose of a polarized plug?
Polarized receptacles are electrical outlets that have two slots: a small “hot” slot and a larger neutral slot. Polarized receptacles ensure that the electrical currents flow along the appropriate wires in the circuit; hot along hot, neutral along neutral.
What is the difference between a polarized and non-polarized power cord?
An appliance with a polarized power cord has a plug that matches the outlet. Only one way will it travel. An appliance with a nonpolarized power cord has a NEMA 1-15P plug, but the prongs are the same, so it can go either way. There are three prongs in a grounded NEMA 1-15P.
Are polarized extension cords safe?
Longer cords can’t handle as much current as shorter cords of the same gauge. Choose cords with polarized or three-prong plugs. For use with larger appliances, thick, round, low-gauge extension cords are best.
How do you tell if a plug is polarized?
The simplest way to tell if your receptacle (electrical outlet) is polarized is if you are able to plug in a three-prong plug (NEMA 1-15 ground Type B) or if a two prong-plug (NEMA 1-15 ungrounded Type A) can only fit with the larger prong on the left.
Is a polarized cord for outdoor use?
A polarized plug is found at the end of an electrical cord on an appliance and on some heavy-duty indoor and outdoor extension cords. Electrical appliances have specific certification guidelines that must be followed to comply with safety regulations in the United States and Canada.
How do you use polarized plugs?
If a polarized receptacle is wired correctly, the narrow slot connects to the hot wire (delivering power to the receptacle) and the wide slot connects to the neutral wire (carrying power back to the service panel). When you plug a light or appliance into the receptacle, its switch controls the hot wire.
Can I plug a non-polarized plug into a polarized outlet?
All polarized and non-polarized plugs will fit into a polarized socket, but polarized plugs will not fit into a non-polarized socket.
How do you wire a polarized plug?
If the plug is polarized, put the hook of the neutral wire over the silver screw in the plug, with the hook going clockwise around the screw. If the plug is not polarized, hook the wire around either prong. Tighten the screw, making sure to sandwich as much copper as possible under the screw when completely tightened.
When did plugs become polarized?
Although polarized outlets and plugs were introduced in the 1880s, they were not popular at first and did not become standard until the mid-20th century.
Why you shouldn’t use an extension cord?
Extension cords can overheat and cause fires when used improperly. Overheating is usually caused by overloading or connecting appliances that consume more watts than the cord can handle. Damaged extension cords can also cause fires. Extension cords should only be used temporarily.
What should not be plugged into an extension cord?
If the power strip or extension cord feels hot, that is a sign that it is overloaded and may start a fire. Rule two: never plug high power capacity appliances, like space heaters, refrigerators, or microwave and toaster ovens into power strips or extension cords.
Can extension cords get wet?
Extension cords get wet. However, you can use them afterward if you take the proper precaution. You don’t have as much to worry about if the water only touched the plastic and rubber sections. Things become far more complicated if the plug becomes wet or if the liquid enters the outlets on the extension cord.
Does a lamp need a polarized plug?
The metal parts of a light, lamp cords, and two-wire extension cords are always separated. Is this true? A lamp, extension cord, or any other cord that’s polarized to begin with, should always have a polarized plug. Don’t use a nonpolarized replacement plug with blades that are the same size.
Does it matter which way you plug in a non-polarized plug?
Many devices only care about the relative potential (i.e. voltage) between the two wires, in that case the polarity (i.e. direction it’s plugged in) doesn’t matter, since flipping the polarity has only one effect of the relative voltage: it flips the sign, but AC has a type of symmetry that means that flipping the sign.
What’s the difference between an indoor and outdoor extension cord?
Insulation is the significant difference between indoor and outdoor extensions cords. Indoor extension cords lack the materials that act as protective insulation to protect against moisture and varying temperatures. Outdoor extension cords are also made durable enough to withstand long periods in the sun.
Are indoor extension cords OK outside?
Indoor extension cords are called that for a reason – they are rated for indoor use. The female socket moulded into the end of the cord is not weather tight. Indoor extension cords left outside for extended periods may break and could lead to sparking, fire and shock.
