Polarized plugs were introduced sometime in the early 1980s I _think_, but I have no reference for that right now. It's a little hard to tell from your photo, but that doesn't appear to be a polarized plug.
Polarized plugs actually came out in 1914. They were never well accepted, so, here is what I can tell you. If you have an old lamp pay more attention to the cord and the socket. When polarized ...
The plugs have three round pins arranged in a triangle, with the larger top pin being the earthing pin. The plugs are polarized and unfused. Plugs are non-interchangeable between current ratings. Introduced in 1934, the BS 546 type has mostly been displaced in the UK by the BS 1363 standard.
These are unpolarized plugs. Older lamps and other devices may well have unpolarized plugs, and some modern electronic devices, such as chargers on computers or cell phones, also have simple unpolarized plugs. It is generally not a problem to plug in an unpolarized plug to a polarized outlet in whatever way it will fit.
Plugs with the two of the same-sized prongs are considered non-polarized because there is no clear distinction as to which prong is for the “hot” side and the “neutral” side. When older devices with a non-polarized two-prong design are inserted into a non-polarized outlet, the polarity (directional flow of the current) would be reversed.
I have noticed on discussions regarding vintage lamps the use of the term polarized plug. What is a polarized plug? When did they start using polarized plugs? I love to buy vintage lamps, usually with intent of selling them on ebay but then I cannot part with them!! I am unaware of this term and it sound like something I should know about.
Tour Start here for a quick overview of the site ... Why are some AC outlets and plugs polarized? Ask Question Asked 8 years, 5 months ago. ... no electricity is even entering the working parts of the appliance. For example, if a lamp is properly wired with a polarized plug into a polarized outlet, and it is turned off, you could stick your ...
A polarized plug allows connection in only one direction. This ensures that electrical components with a higher risk of user contact, such as the shell of a lamp socket, as opposed to the center ...
A polarized plug is easily distinguishable from other plugs because the blade on one side is wider than the other. Consequently, a polarized plug can only be inserted into an electrical outlet one ...
Polarized plugs work as a safety mechanism to prevent electrical shock if you touch an energized part of the appliance. They come in two forms: plugs with two prongs of different sizes and plugs with two flat prongs and a third circular prong underneath. Due to the design of polarized plugs, they ...