The number of electrical appliances you can connect to a single power outlet (single phase) depends on the power rating of the appliances and the maximum current capacity of the outlet and the circuit it is connected to. In general, there are guidelines and safety regulations that need to be followed to prevent overloading the circuit and causing potential hazards such as overheating or electrical fires.
In most residential settings, the standard voltage for a single-phase power outlet is 120 volts (in North America) or 230 volts (in many other parts of the world). The current rating of a standard household power outlet is usually 15 or 20 amps. So, to determine how many appliances you can connect to a single outlet, you need to calculate the total current draw of the devices.
Here are the general steps to estimate the maximum number of appliances:
Determine the power rating of each appliance: The power rating is usually listed on a label or nameplate on the device, and it is measured in watts (W) or kilowatts (kW). If the power rating is given in amps (A) and the voltage is known, you can calculate the power in watts using the formula: Power (W) = Voltage (V) x Current (A).
Calculate the total current draw: Add up the power ratings of all the appliances that you intend to connect to the outlet.
Check the maximum current capacity of the outlet and circuit: As mentioned earlier, standard household power outlets are usually rated for 15 or 20 amps. Check the circuit breaker or fuse that controls the outlet to determine its capacity. The total current draw of the connected appliances should not exceed this capacity.
Consider a safety margin: It's generally a good idea to leave some safety margin to avoid pushing the circuit to its absolute limit. Avoid exceeding 80% of the circuit's maximum capacity for continuous loads.
Keep in mind that some appliances, such as air conditioners, refrigerators, or space heaters, can draw significant power and may require a dedicated circuit to avoid overloading. If you are unsure about the electrical load or how to perform the calculations, it is best to consult a qualified electrician who can assess your specific setup and provide safe solutions.