How to determine wattage of light fixture

How to determine wattage of light fixture. It is important to have the information before installing a bulb into a fixture whether the new bulb matches its wattage ratings or not.

Normally it happens in homes that if a bulb is burnt out, then the household fix any available bulb into the fixture, which is very dangerous because if the new bulb is of higher wattage, then it can lead to overheating the fixture.

The manufacturers who make the light fixtures enjoy hiding information about wattage in unique places.

Although you can find out the information after slightly hard work, mostly it is mentioned on the inner side or on the outlet of the fixture.

Sometimes it is written on the packaging of the light fixtures. You can note it down from there and install the new bulbs according to the wattage ratings for safety from fire hazards.

For more information on this topic, keep reading my research in this article.

How to determine wattage of light fixture

determine wattage of light fixture

It is not a big issue to call an electrition to get information about the wattage fixtures. You can find it on the different parts of the light fixtures.

Do not install an old bulb into a fixture before knowing the wattage because it varies in the different sockets, and when will you shove any bulb into any socket then, you can face the problem of overheating of the bulb or permanent fault to the fixture.

Following are some of the places from where you can get the knowledge of wattage for the light fixtures.

Switch off the power

It is necessary to switch off the power of a room before you change the bulb because there is always a risk of electric shock when you deal with the electrical fixtures.

Direction manual

The first and simple way to check the wattage of the light fixture is through its direction manual.

When you buy a new fixture then, there is an instruction manual also with it by the manufacturers. Each and every piece of information is mentioned in this manual for the users to guide.

Lamp outlet

For some people, it is not difficult to know the wattage of the light fixtures but for those who do not know how to check the wattage of the fixture is very important to know it.

Mostly it is written on the socket or outlet of the lamp. If you inspect the socket from the inside, then you will see a silver sticker.

Complete information about the maximum wattage which you can lodge into the fixture is written on this sticker.

Check the packaging of the light fixture

If, unfortunately, the instruction menu is misplaced from you, then check the packaging of the fixture. The ideal wattage information is written on it to guide the consumers.

It is also important to save the packaging of the electrical appliances because sometimes you need to replace them if they are damaged before the finishing of the warranty card.

See the cover of ceiling bulbs

see the cover of ceiling bulbs

If you want to know the wattage of a covered bulb then the first step is to detach its cover. Then you can check the insulation of the light fixture to get familiar with the detailed information on wattage.

Manual method to finding wattage of light fixture

If still you don’t know the wattage, then there is also an easy manual way to find the exact wattage. But before going into the formula, you must know that V is for voltage and A is for current in amps.

Note down the voltage and current in amps from the label of the fixture. For example, the volts of the fixture is 100V, and the current in it is 2 amp.

  • Wattage= V x A
  • P = 100V x  2A
  • P = 200W

It is a simple way to find the power in the wattage of a light fixture.

Result of the more powerful bulb in fixture

Some people make the mistake of installing a spare bulb into the fixture without knowing the wattage accommodation capacity.

It is a very dangerous act to do. If you install the more powerful bulb in a fixture, then there will be overheating. There is also the risk of permanent destruction to the fixture.


It is important to know the wattage of the fixture before you change the new bulb because it will save you from different issues.

If you install the bulb over wattage in the fixture, then it will damage due to overheating.

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