You’re putting in a new microwave in your kitchen. And you’re thinking about where to plug it in. Your options are, plugging it in a shared outlet or, making a new dedicated outlet.
Does a 1000 watt microwave need a dedicated circuit?
The short answer is yes. A microwave oven is about 60% – 70% power efficient. Therefore, your 1000 W microwave will pull about 1450 watts to 1700 watts. This means you’ll need an outlet that can supply 1700 watts safely. NEC guidelines state that an appliance cannot use more than 80% of the circuit’s rated output. Meaning you’ll need a dedicated 17 amp circuit.
That’s an abbreviated answer. Keep reading as we go into more details about the topic.
Let’s dive right in!
Dedicated Circuit or No Dedicated Circuit?
Let’s get something straight right off the bat. Your best option is to follow the manufacturer’s instructions. That is if the device’s manual tells you to use a 20 amp outlet, follow that. Following the manufacturer’s instructions is the safest option.
Now, what if the manufacturer doesn’t mention anything of the sort? Well, then you’ll need to break out the calculator. But no need to fret. The calculations are simple.
A typical microwave is about 60% – 70% power efficient. This means it can only utilize 60% – 70% of the power it pulls from the wall. Therefore, for a 1000 watt microwave, 60% – 70% of the power pulled equals 1000 W.
Now, assume your device is 60% power efficient. We suggest you take the lower estimate to allow greater room for error. Dividing 1000 W by 60% you’ll get 1666.66 W. Which you can round up to 1700 W.
The next step is considering the NEC regulation. As per NEC regulation, any countertop kitchen appliance can only use 80% of the circuit load. That means 80% of the circuit’s max power output equals 1700 W.
Following the previous pattern, you’ll arrive at 2125 W. You can round this up to 2200 W for ease of calculation. The last step is dividing this by the typical voltage in household wiring, 120 V. Which gives you 18 amps.
A 60% efficient 1000 W microwave oven will, therefore, need an 18 amp outlet. Since typical household circuits are 15 amps or 20 amps, you’ll need a 20 amp circuit.
When putting in a new outlet for the microwave, consider the outlet’s height. It’s an important factor for microwaves.
Any Possible Workarounds?
Yes. There is one little workaround. Say, you have a 20 amp circuit. But it isn’t a dedicated one. You may still be able to use it. But it’ll require a bit more work.
You might’ve noticed that the microwave needs 18 amps for safe operation. But the circuit provides 20 amps. The 20-amp circuit will provide up to 2400 W of power.
Let’s assume all other appliances combined take up less than 700 watts. In that case, you can put the microwave on that circuit. Be wary of plugging in any other appliance in that outlet, however.
Heavy-duty appliances drastically reduce the number of devices an outlet can handle.
Even without plugging anything else in the outlet, you’ll be taking a risk. As any sort of power surge will cause a circuit breaker trip.
If you’re okay with that risk, perform the following steps.
Step 1: Figuring Out the Circuit
First, plug a device in the outlet and turn it on. Next, turn on all the switches in the house. Once that is done, flip all the breakers off. Now, flip the breakers one by one till the desired outlet gets power.
When that happens, turn off all other breakers except for that one. All appliances still on are on the same circuit.
Step 2: Adding Up the Loads
Once you’ve figured out what’s on the circuit, add the wattage of each. If that adds up to more than 700 watts, you’ll need to make a dedicated circuit.
What Are the Necessary Safety Measures?
Does a 1000 watt microwave need a dedicated circuit? Yes, it does. But, the extra headroom allowed by a dedicated circuit isn’t enough of a safety measure. You’ll also need a few extra safety measures.
Kitchen Outlet Requirement
The NEC maintains that the maximum distance between outlets can be 48 inches. No point on the kitchen counter can be more than 24 inches away from an outlet.
Any outlet which is less than 5 ½ feet high has to be tamper-resistant. Tamper-resistant outlets help keep children safe. Here are a few suggestions from us. You can purchase these if you’ve not purchased one in the past.
A common misconception is that tamper-resistant outlets require added force. This isn’t quite true. If your TR outlet requires extra force, you might wanna look into it.
AFCI and GFCI Protection
You should put GFCI protection on all your kitchen outlets. A GFCI outlet’s internal circuit breaker cuts off power when it detects a surge. It mostly does so in case of water spills, thus preventing shocks.
When using GFCI it helps to be aware of the possible problems with GFCI wiring.
In addition, any outlet that supplies power to a heavy-duty appliance should have AFCI protection. AFCI functions similarly to GFCI. That is, the breaker cuts off power in the event of a surge.
The difference is that AFCI detects surges that can cause fires.
Is Higher Voltage Outlet Usable?
Absolutely not. A typical household circuit is 120 V. Two of these can be combined to produce a 240 V circuit. As tempting as it might be, never plug a device in a higher voltage outlet.
Unless the appliance explicitly mentions that it can use either voltage, don’t use a higher voltage. A high voltage outlet will at the very least cause the device to stop working. And at worst brick it entirely.
And that is everything you need to know for a 1000 W microwave oven
Question: Are requirements for built-in ovens the same as they are for countertop ones?
Answer: No. NEC safety guidelines differ based on the type. A built-in oven can only use 50% of the max circuit load. That is, a 1000 watt built-in oven will need a 30-watt circuit.
Question: Does a refrigerator need a dedicated circuit?
Answer: Yes. Any device that draws a large amount of power from the wall needs a dedicated outlet. Putting a refrigerator on a shared circuit makes the circuit prone to circuit breaker trips. It might also cause a fire.
Question: Is a GFCI outlet a necessity for an oven?
Answer: As long as the outlet isn’t within 6 feet of a water source, it isn’t necessary. However, if it is in the kitchen, using a GFCI outlet makes it safer.
Does a 1000 watt microwave need a dedicated circuit? It depends on what else is on the circuit. If all the circuit is running are a few lights, then no. Otherwise, yes.
Following what the manufacturer says is always best. But, if that isn’t an option you can work around the issue. Though it is risky, it’ll still work.
And with that, we bid you farewell. But we hope to see you any time you have a question that needs answering.