So, to answer your question, how many watts can a circuit give before it becomes overloaded? Most typical home circuits are 15 or 20 amps, hence the maximum load before the breaker goes is either 1800 watts (15A x 120V =) or 2400 watts (20A x 120V =) The circuit breaker will be designated 15 or 20. If the circuit is not listed in ohms, then assume it's a 20-amp circuit.
The voltage across a resistive load is equal to the current through it times the resistance. So, if you know one of these quantities, you can calculate the other. In this case, we'll assume that you measured the voltage across the load and found it to be unsafe (more about this later). Then we can estimate the current by dividing the total power used by the total resistance seen by the meter. In this case, it's 1200W divided by 0.12ohms=120A.
Now, let's say that you want to put more than one light bulb on a circuit. Because electricity must flow in only one direction through a conductor, the most efficient use of electricity is if all the bulbs are off when the power switch is turned off. Otherwise, some circuits will be activated while others aren't, which is inefficient.
However, if all the lights must be on at once for safety reasons, there is no way to turn them off individually when needed.
A circuit is overloaded if: A. the total load for a 15-amp circuit exceeds 1,800 watts. (1,800 watts Equals 120 volts multiplied by 15 amps). To discover how many outlets you can have on a 15-amp circuit, look for the amp rating of the circuit in small digits on the circuit breaker switch or fuse. If the number is higher than 15, then this circuit is overloaded.
The easiest way to keep your circuits from being overloaded is to use a circuit breaker or fuse box that limits the number of openings (outlets) available on any single circuit. For example, a circuit breaker that allows only two openings on a single circuit prevents you from putting an overload on the circuit. The more powerful your appliances are, the more care you should take not to overload a circuit. Modern power strips and wall outlets can handle much greater loads than those designed years ago. However old wiring may be hard to track down so it's best to err on the side of caution.
Circuit overloads can cause damage to your appliances quickly due to overheating components. If you're not sure whether or not your circuit is overloaded, turn off all power to your home before checking wires inside your house. If some lights come on while others don't after shutting off the power, you've found the problem location.
If your circuit is overloaded, contact a licensed electrician right away to repair the problem and prevent further damage to your home.
If the power exceeds 2,400 watts, the circuit breaker will trip and the circuit will be broken. The breaker will trip whenever the amount of watts (the unit of electrical power utilized) exceeds the circuit's amp rating. Here are some of the most typical reasons why a breaker may trip:
A fuse has blown. If a fuse blows, you must replace it immediately because it can cause serious damage to your circuit if not repaired quickly. A tripped breaker indicates that there is a problem with one of the branches or poles of the circuit, which means that electricity is being wasted when it shouldn't be. This might indicate a problem with a branch or pole that is about to fail. If this happens during an outage, contact a qualified electrician right away so they can locate the problem and fix it.
The next time your circuit breaker trips, call an experienced residential electrician immediately to determine the cause of the problem. An electric shock can be very dangerous, so it's important that you don't try to fix it yourself. Instead, call an electrician who can check out the situation and make any necessary repairs before you continue working on the wiring system.