Is an electrical extension cord the same as a wall outlet?

Answer 1

The extension cord will extend the power outlet from a wall socket. The voltage will be the same at the end of the cord as it is from the socket. Be aware that extension cord may have a limit, as to how much current it can provide. The cord should be thick enough to provide as much power as the outlet can. It will then be properly protected by the circuit's fuse or breaker. A thin cord may get hot if a large consumer is plugged in, unless the cord is protected by it's own fuse at the plug end.

Answer 2

Differences between an extension cord and wall outlet:

1. A wall outlet is always considered "live", but an extension cord is not live unless it is plugged into a live outlet. An extension cord has no electrical use if it remains unplugged.
2. An unplugged extension cord is nothing but wire plus insulation, while a live outlet is wiring and insulators, plus connected live electricity.
3. If a circuit is overloaded, and assuming it is connected to a breaker or fuse (15amp US), it should blow the fuse or trip the breaker. However, if an extension cord is overloaded, the extension cord adds risks despite a fuse or breaker from the main panel.
4. Standard Wall outlets contain 2 places for prongs to be inserted. Some electrical extension cords contain 2, 4, 6, or 8 places for prongs.
5. Most home extension cords are NOT intended to carry the load demands of a large appliance, or an appliance that regularly redraws a primary surge of electricity. So outlets are used for appliances like refrigerators, microwaves, deep fryers, or anything with a sudden recurring draw. Construction-heavy duty extension cords (often orange; sometimes yellow) are made to carry higher demands of large tools, like band saws, but the heavy-duty cord can only help if attached to a socket that can carry the heavier load (or you'll keep tripping the breaker or blowing the fuse--or cause a fire).

Similarities between an extension cord and wall outlets:

1. Wiring in either an outlet or an extension cord can become old, brittle, broken, or frayed, or lose its insulators. This is one reason an extension cord should NOT be used for any other purposes or stood on, played with, etc.
2. A bad extension cord holds perhaps even more risks than a grounded outlet on an appropriate amp fuse or breaker, but if bad, either one poses risks.
3. Most older outlets or extension cords have prong openings of equal width (example: old house wiring connected on a 15amp fuse). These outlets require an adapter to receive a wider prong-side (I believe the wider prong provides the ground?), with the adapter grounded. Most newer outlets or extension cords have one side made to accept the wider prong; cords only go into the socket one way, not either way.
4. Assuming the outlet is connected to live electricity, and assuming the extension cord is plugged into a live outlet, both conduct electricity.
5. Assuming both are receiving live electricity, one or both can produce a shock.
   
6. Assuming both are receiving live electricity, one or both can overheat and cause fire.
7. The UL rating on small and large appliances should be checked before plugging into either a wall socket or an extension cord.

NOTE: As with ANY electricity situation, risks exist so great care should be taken to make sure your building wiring and extension cord can handle continuous (even short term) electrical draw and any surges produced when a motor first begins to run.