Outlets can be loaded to 12 devices per one circuit. (the recommended load is 8-10 outlets to allow for future expansion). These outlets must be protected by an AFCI breaker. Overhead lighting can be loaded to 12 fixtures per circuit.
Ideally, you should spread as many outlets around your home as possible and assign them to a single circuit. Just keep in mind the maximum load for a single circuit. A good rule of thumb is to assume that there will be a maximum power draw of 1.5 amps for each outlet, allowing 10 outlets for a single 20-amp circuit.
Suppose you have two refrigerators with amp ratings of 5 amps each. In this case, the total amp load would be 10 amps (5 amps + 5 amps), which is well below the 20 amp capacity of the circuit. Therefore, it is safe to operate both refrigerators simultaneously on the same 20 amp circuit.
An easy rule of thumb to follow is that anything that is fixed (installed and not moved around) needs to be on a dedicated circuit. These sorts of things would include: Refrigerators and standing freezers. Heating and cooling systems.
The National Electrical Code's guidelines don't specify a specific limit to the number of outlets you can install on a single circuit. This is because the number of outlets matters far less than what those outlets are used for.
The National Electrical Code (NEC) recommends following the 80% capacity rule, and some states or local municipalities may require you to follow this rule when installing outlets and lights on a circuit. The 80% rule states that you should not load more than 80% of the circuit's maximum load.
Practically, you can place as many outlets as you want on a 20 amp circuit. However, most professionals recommend a maximum of 10 outlets.
The National Electrical Code requires dedicated circuits for major electrical appliances such as refrigerators, stoves, washers, dryers, and electric water heaters because they ensure that appliances can operate safely without overloading the home's electrical system.
In the Laundry Room
Your laundry room should have a dedicated circuit of at least 20 amps. If you have a gas dryer, both your washing machine and gas dryer may be plugged into the same outlet. If you have an electric dryer, it will need its own dedicated 20-amp, 220-volt circuit.
Appliances That Do Not Need a Dedicated Circuit
Many compact or portable appliances do not need dedicated circuits. Examples include portable fans, ceiling fans, countertop cookers, food processors and small space heaters.
You should never use a microwave and refrigerator on the same circuit The NEC requires that permanent microwave devices have a dedicated circuit. The same could be said about refrigerators. However, you should be clear on which type of refrigerator is in question.
The issue with double tapping is you could technically have a loose connection or an overloaded breaker since the breaker is not designed for two wires. A loose connection can potentially spark or arc. Furthermore, an overloaded breaker could continuously trip or overheat.
You should have refrigerators and freezers installed on a 15-20 amp dedicated 120 volt circuit. This will avoid an electrical overload due to your current wiring not being capable of handling the additional power.
Plugging two refrigerators into the same outlet is not recommended due to potential safety risks and the likelihood of overloading the electrical circuit.
A single outlet should ideally cater to only two to three devices, keeping total wattage within the safe usage threshold, and special caution is needed when connecting high-wattage appliances.
If too much current is drawn, usually a circuit breaker would trip or fuses would blow, but this is never guaranteed. The results of overloading a circuit could range from a damaged appliance to starting a fire. That is because when too much electrical current flows thorough a circuit, things can overheat.
Microwave ovens come in different varieties and sizes. Some are countertop models, and other microwaves mount above the stove. Although it's not uncommon to see microwave ovens plugged into standard appliance outlets, larger microwave ovens can draw as much as 1500 watts, and these need their own dedicated circuits.
As others have said it's not a good idea. The circuit breaker will likely trip if both are turned on at the same time. Or worse you could over heat the line and potentially start a fire if the breaker didn't work.
Most washing machines need their own dedicated circuit due to the amount of power they use. Planning out the electrical for your new laundry room? Make sure you give your washer its own dedicated circuit!
The oven must be operated on a SEPARATE(dedicated) CIRCUIT. No other appliance should share the circuit with the microwave oven. If it does, the branch circuit fuse may blow or the circuit breaker may trip. The oven must be plugged into a 15 AMP or 20 AMP, 120 VOLT, 60 Hz GROUNDED OUTLET.
So yes, both these items are supposed be in independent circuits as you know. If you have both units running at the same time, it's possible the breaker or GFI would trip because the freezer starting up at the same time the motor starts up can cause draw too much power to trip the breaker.
Absolutely not a good idea! Your dishwasher needs a 20 Amp circuit, usually can share with garbage disposal only. Your oven, depends on if it's gas or not, usually can need 30, 40, or 50 amps. If it's gas then it's a 20 Amp for ignitor but I still recommend having seperate circuits.
Note that a 14 gauge wire on a 20 amp circuit is not the correct size, as it is only rated to handle up to 15 Amp in residential applications. Using 14 AWG for a 20 Amp breaker will result in overheating and a risk of electrical fire. Using a 10 AWG wire for a 20 amp circuit is possible and safe but not cost-effective.
#12/2 AWG cu conductor should be protected by 20A, 1P breaker. Every outlet is allowed to carry 1.5A at 120V. You may have 12 outlets for that circuit and the load = 12*1.5 = 18 A which is within the safe load the 20 A can carry.