Electrical outlets with polarized receptacles have two slots: a small “hot” slot and a larger “neutral” slot. Polarized receptacles ensure that electrical currents flow via the circuit’s proper wires: hot to hot, neutral to neutral.
What is the purpose of polarized sockets?
Most appliances would function if they were plugged in backwards. However, aligning the polarity of the device and the house wiring provides a level of protection. This is why most appliance connectors are polarized, allowing them to be plugged in just one way: neutral-to-neutral, hot-to-hot.
What’s the best way to use a polarized plug?
- If the plug is polarized, wrap the neutral wire’s hook around the silver screw in the plug clockwise. Hook the wire around either prong if the plug isn’t polarized. Tighten the screw until it is entirely tightened, being sure to sandwich as much copper as possible beneath the screw. When tightening the screw, keep pushing the wire under the screw using your fingernail or thumbnail, or a very small screwdriver if you don’t have any nails. Push the wire back under the screw every time it starts to squeeze out, backing the screw off if necessary. You should be able to keep pulling the wire beneath the screw if you screw it down slowly enough.
What does it mean to be polarized in electrical terms?
field of electricity When an electric field distorts the negative cloud of electrons around positive atomic nuclei in the opposite direction of the field, polarization occurs. Because of this little charge separation, one side of the atom is slightly positive and the other is slightly negative. Some polarization is induced by molecules rotating into the same alignment under the effect of the electric field in some materials whose molecules are permanently polarized by chemical forces, such as water molecules. Polarization can be measured in a variety of ways.
Is it safe to use a plug that isn’t polarized?
Because there is no clear differentiation between which prong is for the “hot” side and which is for the “neutral” side, plugs with two of the same-sized prongs are considered non-polarized. The polarity (direction of current flow) is reversed when older devices with a non-polarized two-prong design are inserted into a non-polarized outlet. When the polarity is reversed, the circuit is left open, which can result in electrical arcing or shocks. Fortunately, most receptacles in modern American homes are polarized. For newer electronic devices, even though the two-prong design doesn’t feature a grounded wire, most non-polarized plugs are double-insulated as a safety precaution. To prevent electrical shocks and shorts, there are two layers of insulation between any live wires and any metal parts within the appliance.
When did polarized plugs become necessary?
Although polarized outlets and plugs were originally developed in the 1880s, they were not widely adopted until the mid-twentieth century. The 1962 edition of the National Electric Code (NEC) is the first to mention polarized receptacles, requiring outlets to be both grounding (3-prong) and polarized. In a vintage home with ungrounded 2-slot receptacles, we occasionally see an unpolarized outlet still in place, such as the beaten, charred, and ready-to-retire one pictured below.
Is it possible to connect a non-polarized plug to a polarized outlet?
Electrical or pin can both be used to describe polarized. Electrical polarization refers to a specified manner of connecting circuit wires to the plug or socket. These circuit wires must be connected correctly to the plug and socket’s line, neutral, and ground contact points. The electrical circuit is mirrored by the components. Pin polarization refers to the fact that the pins are aligned in a specific direction, with just one way for the plug to fit into the socket. Note that just because a plug is pin polarized doesn’t mean it’s also electrically polarized.
A polarized socket will accept both polarized and non-polarized plugs, however polarized plugs will not fit into a non-polarized socket. Equipment-specific requirementswhat is necessary within the equipment’s internal circuitrydetermine the necessity for one or the other. “It depends on whether the end product’s requirements demand a specified electrical path of the line current, or whether it doesn’t matter which leg of the power is connected to the internal circuitry,” said Mike Winders, Interpower’s Product Development Specialist.
Is a polarized plug required for a lamp?
Damaged plugs and frayed, nicked wires are dangerous and must be replaced. It’s simple to install a new plug, but there are a few guidelines to follow.
Lamp cords and two-wire extension cords are always polarized to prevent shocks from the metal parts of a light. This signifies that the plug has a small hot wire blade and a broad neutral wire blade, and the wires feeding those blades should not be reversed when installing a new plug. For a lamp, extension cable, or any other cord that is polarized to begin with, always use a polarized plug. Never replace a polarized plug with a nonpolarized replacement plug with the same blade size. (On double-insulated tools and some appliances, nonpolarized connectors are common.)
What is a two-prong polarized plug?
Electrical outlets with polarized receptacles have two slots: a small “hot” slot and a larger “neutral” slot. Polarized receptacles ensure that electrical currents flow via the circuit’s proper wires: hot to hot, neutral to neutral.
Why are there two holes in electrical plugs?
If you disassemble an outlet and examine the contact wipers into which the prongs slip, you’ll notice that they have bumps on them. These bumps go into the holes to let the outlet grab the prongs of the plug more firmly. Due to the weight of the plug and cord, this detenting prevents the plug from falling out of the socket. The contact between the plug and the outlet is also improved.
