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The Ultimate Dimmer Switch Quiz
by Staff
A dimmer switch allows you to create romantic ambience at the touch of a button. Take this quiz and find out if you know how it performs its mood-setting magic.

When was the residential light dimmer switch invented?

  • 1955
  • 1959
  • 1962

What is the average life expectancy of a dimmer switch unit?

  • more than 10 years
  • more than 20 years
  • more than 30 years

What is the name of the component that dims the light in older types of dimmer switches?

  • variable resistor
  • capacitor
  • transformer

What is a conductor choke?

  • a small transformer
  • a coil of wire around an iron core
  • a device that does not conduct energy well

What is the disadvantage of older resistive-only dimmers?

  • The light bulb burns out faster.
  • The light tends to flicker.
  • There is a lot of heat from the dimmer.

Is there an energy-use advantage when you compare the older resistive-only dimmers to the newer models?

  • Old-style dimmers use more energy.
  • Old-style dimmers use less energy.
  • Old-style dimmers use the same energy as the new type.

How do modern dimmers control the brightness of the light?

  • by shutting the voltage off and on rapidly
  • by changing the voltage using a transformer
  • by using two variable resistors instead of one

In the U.S., how many times a second does alternating current go from positive to negative?

  • 50 cycles a second
  • 60 cycles a second
  • 70 cycles a second

How many times a cycle does a modern dimmer shut off the current?

  • two times
  • three times
  • four times

How many times a second does a modern dimmer shut off the current?

  • 60 times
  • 120 times
  • 180 times

What does the turn-on value regulate?

  • the speed of the electric current coming into the light
  • the brightness of the light
  • the amount of electricity being used by the light

What happens to the light bulb when the dimmer is switching the light on at its fastest?

  • It is as dim as possible.
  • It is as bright as possible.
  • It is not on at all.

What component is present in both modern and older types of dimmers?

  • firing capacitor
  • choke coil
  • variable resistor

How does the variable resistor work in a modern dimmer?

  • It delays the current.
  • It speeds up the current.
  • It has no effect on the current.

When a dimmer's variable resistor arm is all the way to the right, how bright should the bulb be?

  • the brightest level
  • half as bright as it can be
  • the dimmest level

What could be the cause of buzzing from a cheap dimmer switch?

  • heat from the variable resistor inside the switch
  • the switch cover not being flush against the wall
  • sudden voltage jumps from chopping the electric current

You installed a new dimmer, and now your TV is making funny noises. What went wrong?

  • You didn't properly disconnect the electricity to the wiring before installing the dimmer.
  • You accidentally wired the dimmer switch to the same electrical line that runs to the TV.
  • You purchased a cheap dimmer that is poorly designed.

Modern dimmers contain a component called a triode alternating current switch (triac) that actually does the work to dim your lights. What does the triac do to the electric current to achieve a dimming effect?

  • It reduces radio interference, such as buzz, caused by dimmer components.
  • It switches alternating current on and off so fast it makes a light appear dim to the human eye.
  • It acts as a firing capacitor to send current to an incandescent bulb.

How does the dimmer used to control stage lighting differ from cheaper residential dimmer switches?

  • The triac in a stage lighting dimmer is much bigger and has a higher tolerance to extreme conditions.
  • These dimmers are essentially the same inside except the components are hardier.
  • Stage dimmers must be noise free, so they contain a more expensive device called an autotransformer to reduce current to the lamps instead of a triac.

How do touch-pad dimmers differ from regular modern dimmers?

  • They function the same on the inside.
  • They employ autotransformers instead of triacs.
  • They combine an autotransformer and a triac.