Until you reside in an older house with two-prong retailers, you in all probability don’t put a lot thought into plugging and unplugging digital units and home equipment.
However sooner or later, you’ve seemingly seen that some plugs have two prongs, whereas others have three, and should have even questioned why that’s, and what the distinction is between them. Perhaps not. Both means, right here’s what to know.
Two-prong retailers vs. three-prong retailers
Earlier than entering into plugs, let’s begin with the retailers. Two-prong retailers had been launched in 1962, however not everybody made the swap immediately: It’s commonplace to seek out them in some properties constructed all through the remainder of the Nineteen Sixties and even into 1970s and 1971.
After that, three-prong retailers turned the norm, and stay so to at the present time—though, as you’ll be able to see within the graphic under, they’ve gotten more and more superior over time, providing further security protections.
Now, let’s discuss holes. Each two- and three-prong retailers have two parallel vertical openings:
- The slender opening on the fitting (i.e. the “scorching” slot) offers entry to the new wire
- The broader opening on the left (i.e. the “impartial” slot) is for the impartial wire
Three-prong retailers even have a 3rd opening under the slots (i.e. the “floor”), which connects to the bottom wire.
We’ll flip it over to the professionals at Shockley Electrical to elucidate what occurs subsequent:
While you plug a tool with two prongs into an outlet, energy flows from your property’s electrical panel by way of the new prong, to your machine (powering it within the course of), and again to the impartial prong, which sends the electrical energy again to the breaker field and completes the circuit.
No less than that’s how issues are supposed to work.
Why three prongs are safer than two
Let’s say there’s an surprising burst {of electrical} present (greater than the 120 volts most retailers are designed to deal with), or a free wire inside an equipment is available in contact with its steel case.
The present has to go someplace, so it travels by way of the equipment—probably damaging or destroying its electrical elements alongside the way in which—and into your physique, leading to a doubtlessly severe shock. The present may additionally make its means into the construction itself and trigger a fireplace.
However that wouldn’t occur with a three-prong outlet, as a result of the surplus electrical present could be despatched again to the primary electrical panel (which needs to be grounded), moderately than the consumer or the home. Or, if it’s a three-prong floor fault circuit interrupter outlet (GFCI)—the type with the buttons, present in bogs—the breaker would detect it, and instantly cease the stream of electrical energy to the outlet.
Why don’t all new home equipment and digital units have three-prong plugs?
Provided that three-prong plugs are thought-about safer, you could be questioning why, 60 years after the introduction of three-prong retailers, some new home equipment have two-prong plugs.
In brief, two-prong plugs are cheaper to make, so producers will use them each time they’re ready to take action and nonetheless meet the requirements of unbiased security testing organizations like Underwriters Laboratories (UL).
Since 1969, three-prong plugs have been required for main home equipment, however two-prong plugs are nonetheless used on “double insulated” home equipment, which have two ranges of insulating supplies between their electrical elements and the exterior surfaces folks contact. This offers safety towards fireplace and getting shocked, even with out the grounding prong.
Can I exploit an adapter to plug three-prong plugs into two-prong retailers?
Technically sure, this works, but it surely’s not thought-about secure. Generally known as “cheater plugs,” “cheaters,” or “pigtail adapters” they could be a handy workaround, however when utilized in an outlet with out a devoted grounding connection, these adapters provide no safety towards fireplace, electrical shocks, or harm to the machine that’s plugged in.
And this could go with out saying, however don’t minimize the third prong off of a plug so it might probably match right into a two-prong outlet. Once more, even when it does assist you to energy on the equipment, you’re placing your self, your property, and the equipment in danger.
So does this imply it’s a must to have your own home—or no less than components of it—rewired? Whereas that’s essentially the most everlasting answer, it’s not in everybody’s price range. At this level, your finest guess is to seek the advice of a licensed electrician to seek out out about your choices, and go from there.
