How many light fixtures can you put on a 20 amp circuit?

Answer 1

Asking how many lights can go on a branch circuit for lights is like asking "How long is a piece of string?". It is impossible to give a general answer because the total number of lights that can be installed will depend on the wattage and amperage drawn by each light and on whether or not they will all be switched on together at the same times of day or night.

If you cannot work out the total amperage of the lights you want to use at any time, compared to the safe load current of the circuit breaker on your lighting circuit, the best advice anyone should give you is to call a licensed electrician for advice.

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As always, if you are in doubt about what to do, the best advice anyone should give you is to call a licensed electrician to advise what work is needed.

Before you do any work yourself,

on electrical circuits, equipment or appliances,

always use a test meter to ensure the circuit is, in fact, de-energized.

IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOB

SAFELY AND COMPETENTLY

REFER THIS WORK TO QUALIFIED PROFESSIONALS.

Answer 2

The number of light fixtures you can put on a 20 amp circuit will depend on the power consumption of each fixture. As a general guideline, you can typically connect around 10-12 average light fixtures on a 20 amp circuit. It is always recommended to consult with an electrician to ensure that you are not overloading the circuit.

Answer 3

To figure out wattage, you multiply the Volts x Amps.
If you are using 120 Volt current, multiply times 20 Amps = 2400 W
This is the point at which the breaker should trip, so you don't want to put 2400 W on the circuit. However, if we take 2400 W / 96 W per bulb, we get 25 bulbs. 25 bulbs would trip the breaker, so you would want less than that. Keep in mind that some devices use more energy when first turned on than while running, so depending on your bulb and fixture, you may need even fewer on your circuit if you plan to have them all on at the same time.

Answer 4

You want to size for 80% or rated current. In this case 16 amps. At 110 volts nominal this is a total of 1760 watts for incandescent bulbs. So if you had 100 watt bulbs you could have 17 100 watt fixtures. Of other wattage fixtures just divide into 1760 watts.

Answer 5

You want the total amps to be 80% of 20 Amps or 16 Amps. A 60 Watt incandescent bulb draws 1/2 amp. Fixtures are rated as to how many watts they can support, so in case of all 60 watt bulbs you could have 32. This usually not practical.

Answer 6

It depends upon how many will be on at the same time and how many are turned on at the same moment. If they are all left on all the time, you would derate the branch to 80 percent and divide the available power by the unit power (i.e., 1,760 watts divided by 32 is 55).

However, you must also calculate the possible overload during startup of 55 simultaneous ballast circuits, which could draw well over 60 amps for a few seconds.

Answer 7

That depensds on the total amp draw of the fixtures. The most amp draw you can safely have on a twenty amp breaker is sixteen amps, per the NEC.

Answer 8

A 20 amp circuit can be loaded to 16 amps. Total the fixture amperage until you get to 16 and that will be the amount of fixtures you can put on the circuit.

Answer 9

20 amps * 120Volts = 2400 watts

2400Watts *80% = 1920 watts allowed on circuit.

1920watts / 65 watt light bulb = 29 bulbs