Most electric devices can be activated with one action. From cell phones and light bulbs to computers and flashlights, these units usually have a single “on” dial, button, or switch that successfully turns them on.
Sometimes, you need to click the light switch twice to turn the lamp ON because of the three-way working mechanism of the lamp. Some lamps give off light at three levels of intensities namely, low, medium, and high. The lamp is programmed to glow with maximum brightness only at the ‘high’ level. .
So when you click the light switch once, it changes to the medium level settings and glows brightly when you click the switch again. Such lamps are known as three-way lamps because they work at three different levels of the light switch.
If you have to click a lamp twice to turn it on, then it could be because of three reasons:
- You might be using a regular bulb instead of a three-way one.
- If you have a three-way bulb, then the lower wattage element may have stopped working.
- There might be a defect in the lower wattage element.
This article will explore the reasons why you have to click lamps twice to turn them on, as well as explain these reasons in greater detail.
Table of Contents
The Light Bulbs
In order to understand why a lamp needs to be clicked twice in order for it to work, you have to understand how light bulbs work in general. In their most rudimentary form (dating back to at least the 1870s) light bulbs consist of a thin strip of metal — enclosed in a gas-filled glass container.
This thin strip of metal — which is constructed out of tungsten — is called a filament. The filament is attached to wires that run a current of electricity through the bulb. Once the bulb has electricity flowing through it (after it is set in the “on” position), a few things happen.
The first thing that happens is that the electrons in the current collide with the atoms of the filament. This causes the filament atoms to vibrate, gain energy, and expand their own electrons away from the filament atoms’ nuclei.
The next thing that happens is that these excited electrons start to lose energy. They return down to their normal orbits around the filament atoms’ nuclei.
As the electrons return down, they release energy — which produces a notable amount of visible light and heat. This is the process that causes light bulbs to light up after you switch them on.
A note here: the original light bulb, with the filament and sealed gas interior — is also known as an incandescent lamp or incandescent bulb, distinguishing it from the later-produced light-emitting diodes (LEDs) and fluorescent lights.
The Three Way Bulbs
Some incandescent light bulbs are constructed with more than one filament. In this case, there are two filaments that work singularly or together to create different levels of light emittance.
This type of bulb is called a three-way bulb. A common example is a three-way bulb that has two filaments: one at 50 watts (a watt is a unit that is a measure of electric power), and one at 100 watts.
When this type of light bulb is turned on, it can operate at a low level — using only the 50-watt filament. If switched to a higher setting, it can operate at a higher setting, using the 100-watt filament.
When switched to its highest setting, the two filaments are simultaneously turned on together. This now-operation of the two different watt levels (one at 50 watts and one at 100 watts) creates a combined output of 150 watts.
Advantages of Using Three-Way Bulbs
Three-way bulbs are great for home use as they come with a few advantages over regular bulbs. For
one, it provides you with a more customizable lighting experience in your home. When you are working
on your PC or watching TV, you might not need the light to be too bright. With a three-way bulb, you
can set the light to a lower intensity with a simple click. When you want to read a book or need more
light to search for something, you can set it to more brightness.
It also helps to save money in the long run as long as you use them properly. With the ability to change
the brightness of the bulb, you can save money on your power bill. With a normal bulb, you can’t do
anything and have to pay for the amount of time you leave it on. With a three-way bulb, you can set it to
low light when you don’t need a lot of light which will require less power. On top of that, you can also
opt for an LED three-way bulb to save even more money.
Do remember that to use a three-way bulb, you need a three-way socket and a rotary switch. Without
them, you won’t be able to enjoy any of the benefits. If you are unsure whether you have a three-way
socket, all you need to do is look for three connection points. You can also go online and check out
pictures of a three-way socket to know what to look for.
Three-Way Lamps
In lamps that can accommodate a three-way bulb, you will be able to switch between three settings — 50, 100, and 150 watts, for example. These types of lamps are called three-way lamps.
With three-way lamps, you can adjust between levels of low, medium, and high light — and do so quite drastically, without having to result to resort to dimming or changing bulbs specifically for this purpose.
How to spot a three-way lamp?
You can spot a three-way lamp by looking at the socket. While standard sockets have two points of contact between the bulb and the socket, a three-way lamp has an additional point of contact. The three points of contact are as follows.
- The metal contact is located at the center of the sockets. This comes in contact with the brass tab of the bulb
- The contact between the threaded base of the bulb and that of the socket
- A small ring contact that is situated between the other two contacts
Can you put a three-way bulb in a one-way fixture?
Yes, you can put a three-way bulb in a one-way fixture without having to worry about any hazards. However, the bulb will be unable to perform the functions that it is designed to. It is because the one-way fixture is designed to work at two levels- ON and OFF. Therefore, when you fit a three-way bulb in a one-way socket, you will have only ON and OFF conditions rather than having four levels- low, medium, high, and OFF.
Socket Configurations
Standard incandescent bulb sockets — where the bulb is placed — have a configuration that involves two electrical contacts. With this type of socket, there is one hot contact in the middle of the socket, and one neutral contact on the edge of the socket.
The hot contact corresponds with the base of the standard bulb — the bottom tip, specifically. When electrons flow out from a power source, this creates a connection that conducts live electricity from the power source, then through the hot contact, then through the filament.
Three-way bulbs have a different socket configuration than standard incandescent bulbs. In three-way bulb sockets, there is one more electrical contact present.
This contact corresponds to a three-way bulb’s base — which typically has a brass ring fitted to it. This brass ring/electrical contact is another hot contact meant to accommodate the second filament.
Once through the filament, the neutral contact then brings the electricity back to the power source, completing a circuit. This is how electrons flow in any closed electrical system, they must have a complete circuit in which to travel.
Clicking a Lamp Twice
But what happens when you use a normal incandescent light bulb with a three-way lamp socket? Well, with one more click, the lamp will still work.
This is because most three-way lamps can accommodate normal incandescent light bulbs. But the problem is that normal incandescent bulbs only have one filament — that can only assume an “on” or “off” position.
With a standard bulb in place, clicking the three-way lamp once will only get the lamp to skip the “low” contact setting (or the “high” contact setting, as the case may be). This will not result in the light turning on at all.
But once the lamp is clicked again, this will bring the standard bulb to the “medium” contact setting. This is the default setting that three-way lamps assume for standard light bulbs. Now, the standard incandescent light has been activated — and it will light up.
Conclusion
Three-way lamps are often compatible with standard incandescent bulbs — and this is why you have to click them twice in order for them to work.
But as long as you click the lamp to the “medium” contact position, a standard bulb should turn on. This explains the extra click needed — to get a lamp to light a room.