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A little.

First off, most modern dimmer switches aren't rheostats. Those have been supplanted by TRIACs (triode for AC), and later, IGBTs (insulated gate bipolar transistors). For both of these, their mode of action is to change the duty cycle of the AC wave (duty cycle is time on versus cycle time) such that less power per cycle is put through the bulb. This is more efficient than a rheostat, in that, there isnt as much resistive loss across the dimmer.

The resistive loss is where the "a little" comes in. For all three types, a small amount of the power put through the dimmer is dissipated as heat - however, this is significantly less than the reduction in output power to the bulb, whatever the type.

An ideal dimmer would have 100% efficiency - that is, for a given setting, it would dissipate no heat, and the bulb would be the only thing on the circuit consuming power. However, no component is ideal, and modern dimmers typically consume under 1% of their power throughput (so if it's passing a total of 1W, it'll consume less than 10 milliWatts).

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โˆ™ 2015-07-15 21:41:03
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Q: Does a dimmer switch rheostat consume the electricity that the light fixture is not receiving?
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Related Questions

Does a down light consume less electricity?

The fixture construction has nothing to do with the amount of energy that the fixture uses. It is the lamp in the fixture that draws the amperage. This amperage times the fixtures voltage is what gives you the fixtures wattage. W = A x V. Watts = Amps x Volts.

Buzzing noise from light fixture?

A buzzing noise from a standard incandescent lighting fixture can be caused by a short in the lighting circuit (which is dangerous), or in some cases it can happen using a rheostat that is not all the way on or all the way off. The larger the physical size (not necessarily wattage) of the filament, the more likely it is to buzz using a dimmer -- these bulbs are designed for 120 volts, and using a rheostat gives less voltage to the lamp.A tube fluorescent fixture can make a buzzing noise if the ballast (small electrical box inside the fixture) is beginning to fail.Some outdoor fixtures are inherently noisy, such as a sodium arc lamp. In this case, there is really nothing to be done about it.

If I remove two of the four lamps in my fluorescent fixture to save electricity should they be on the same ballast?


If you turn on a lamp without a light bulb do you still use electricity?

No power is used. The lamp in the light fixture is the load of the circuit. The load resistance is what makes the current flow. When the current flows through the filament's resistance, heat and light are generated. With no lamp in the fixture, the circuit's voltage potential is still at the socket contact points and if touched could cause you a shock. This is a good reason to shut the fixture off at the switch when removing the burnt out bulb and replacing it with a new one.

Why we do need damp cloth to dust furniture and fixture?

The moisture prevents buildup of static electricity that attracts the dust to the furniture.

Turning off or unplugging electrical fixtures which saves more money?

Turning off an electrical fixture is a good way to save money, but unplugging it is better. Since you turned off the appliance, and not able to unplug the cord, still it will consume some electricity. So when you unplug it, you save more money!

Why would their be Power on the neutral side of a light fixture?

There would be power there because the "neutral" is the path electricity mostly used to return to its source. All electricity has to return to its source somehow.

How much electricity does a fluorescent fixture use?

Look at the ballast and there you will find an amperage that the ballast uses. Also find the voltage that the ballast uses. Use this formula to fine the wattage of the fixture. Watts = Amps x Volts.

How many watts will a ballast consume for 3 20 watts tubelights?

Check the ballast for the amperage and multiply it by the working voltage. This will give you the wattage that the fixture draws.

What does hard wired mean in electricity?

The power supply is wired directly to a fixture or piece of equipment instead of having a cord that you plug into an outlet.

Is a fan a fixture or furniture?

It would be a fixture.

Is a lock a fitting or a fixture?

A lock is a fixture, same as a light, sink, tub. A fitting is usually a part of a fixture, or a fixture is made up of fittings.

How do you use the word fixture in a sentence?

The landlord hired an electrician to replace the damaged lighting fixture. The famous author was virtually a fixture in our restaurant whenever he was in town.

What does the electrical terminology of the word - fixture - mean?

"Fixture" generally refers to things permanently attached to the structure. A light fixture would be one example, screwed to the wall or ceiling. The light fixture, also called a luminaire, would include devices for holding the lighting elements, supplying electricity to them, enclosing the connections for safety, and means for attaching it to the electrical supply permanently. A "fixture" could, in theory, dangle from a cord permanently attached to a suitable support. For contrast, a cord-connected device would not be a fixture. In fact, it is often illegal to use cord and plug on any appliance that is permanently attached (e.g., screwed in or with water pipes attached).

What does watt mean in lighting?

It is the consumption that the fixture uses. It is found by multiplying the voltage the fixture operates on by the amperage the fixture draws.

How would one go about installing lighting in their ceiling?

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Is a fluorescent light grounded?

If you are talking about the lamp then the answer is no. If you are talking about the fluorescent fixture, it should be. It is the fixture grounding that helps the tube to ignite. because of the close proximity to the metal of the fixture. There are many occasions when the fixture will not operate, but as soon as the ground is connected the fixture operates fine.

Light fixture does not turn on when connected to ceiling with power?

Is this a fluorescent fixture? Most fluorescents will not start if the fixture is not grounded. Make sure the fixture has the branch circuit ground wire properly connected.

How do you wire a 220 volts light?

The light is wired the same as any voltage fixture. Bring the source voltage to the fixture and connect it to the two fixture wires. If you want to control the off-on of the fixture take the source voltage to a switch first and then out of the switch to the light fixture.

Is a light bulb considered a fixture?

A fixture is what the light bulb goes into.

Where does the grounding wire from a fixture get grounded to if there is no wire in box?

body of fixture

Changing bathroom light fixtures.?

You will need basic hand tools such as screwdrivers. Of course, you will need a new light fixture and bulbs. You will need to locate the breaker to turn off the electricity on that circuit, and you will use a wire stripper and most likely some wire nuts to connect the new fixture.

Is it okay to fix bathroom lighting by oneself or should one hire a contractor to do it?

There are many online tutorials to help you learn how to install light fixtures. If you have basic tools, and are careful to ensure that electricity is turned of to the fixture during installation, you can very successfully install a fixture on your own and save a lot of money.

What do you do when you can't connect the ground wire to the fixture?

you can ground it to the fixture electrical box.

What is a key less light fixture?

It just holds the bulb, does not have a switch in the fixture.