Microwaves normally operate with five to 15 amperes of current. There are different factors that affect the features of microwaves, such as power, size, manufacturing features, and model, which affect current flow. By getting details of the amperage of the microwave, we get safe operation and help to manage the energy of the house.
In this tutorial, we will cover details of microwave ampere usage and related factors. So let’s get started.
What are amps, volts, watts, and running watts?
- Before getting details of ampres of microwave must know some basic details. These are important for understanding the working of a microwave.
Amps
- For microwave amperes, it shows the electrical power needed for the device’s operation. For high watts of microwave, it needed a high current.
Amps = Watts/Volts
Volts:
- Voltage is the potential difference that is used for current flow in a microwave. In the USA, microwaves and other household devices operate on 120 volts.
Watts:
- Watt is used for showing power, which defines the rate at which energy is produced. In the case of microwave watts, they define the power used for cooking and heating food.
Watts = Volts × Amps
Running Watts
- Running watts shows power used on the microwave when working continuously. By getting details of oven running watts, we get the energy use and its effect on the bill.
Running Watts = Running Amps x Volts
How Many Amps Microwave Wattages Use?
Microwaves come with different power values and sizes. The current used for microwaves is based on voltage and wattage. There are different types of microwaves, like small ones that use less power and larger ones that use more power. Ampers for different sizes of microwaves are as
Small-level microwave
- A small-sized microwave generated up to 800 watts of power. that is commonly used in RVs and small kitchens, and it uses less power.
- It uses five to seven amperes for a 120 V circuit, and in the case of a 240 V circuit, it uses about 3.5 amperes, and it is preferred for limited power uses.
Medium level Microwaves
- Mid-level microwaves use 900 to 1200 watts of power. These are commonly used ovens at home. since it helps to cook food fast
- With a 120V circuit, it uses 8 to 10 amperes, and a 240V circuit uses up to five amperes. It operates well, but the breaker trips when a larger number of devices are operating at the same time when it works.
Larger size Microwaves
- A microwave that uses power in the range of 1300 to 1800 watts is called a larger-sized microwave. Their cooking and heating power is high in speed.
- Its current for 120-volt circuits is 11 to 15 amps and 7.5 amps for 240-volt circuits. This microwave has an overload management system
Commercial types
- Microwaves that use more than 200 watts are called commercial types. These models are parts of restaurants where high-quality food needs to be heated and cooked.
- for120 circuit its ampere capcity is 16ampesand 240volts circuits uses 8 ampers.
Microwave Power and Amp chart
| Microwave Wattage | 120V Circuit | 220V Circuit |
| 600W to 800W | 5 to 7 amps | 2.5 to 3.5 amps |
| 900W to 12,00W | 8 to 10 amps | 4 to 5 amps |
| 1,300W to 1,800W | 11 to15 amps | 5.5 to 7.5 amps |
| 2,000W+ | 16 amps | 8 amps |
How to measure Microwave Amps
The amperage of the microwave is based on the electrical load and managing circuit overloading conditions. For measuring the amperage of a microwave oven, different techniques are explained here.
Manufacturer Datasheet
- The basic method for finding how many amps a microwave needs is to check the manufacturer’s data that is mentioned in the user manual. Normally, you have seen a data label on the microwave body where all details are mentioned, like amperage and wattage. such as a microwave with a rating of 1200 watts and 120 volts, which uses 10 amps
Calculate Amps from Wattage
- By getting details of the wattage of the microwave, we can find the amperage if it is not written, and we can measure it easily. For microwaves with 1000 watts with 120V circuits, their amps are
Amps = Wattage/ Volts = 1000W ÷ 120V = 9 amps
Microwave Power Meter
- When fluctuating power occurs that ampere uses of microwave. In this case, measure the amperage and power of the microwave by using a power meter connected to the outlet. The meter shows readings of amperes and watts with running and starting amperes.
How many amps are needed? Microwave on Startup?
When we first turn on the microwave oven, it gets a high current for a short time; that abrupt power increase is called startup amp and is used for reducing the starting resistance of the microwave that it faces during operation.
To get an idea of how many amps a microwave uses on startup, there is a need to understand some terms and differences that are explained below.
Startup Watts and Running Watts Differences
- Startup watts are called maximum power, which commercial microwaves use for starting power. starting surge high since some internal parts, like the fan and magnetron, have high resistance
- The running watts of a microwave is the power used during regular operation when it gets power from a source. When the microwave starts operating, the initial power surge reduces the rated wattage.
- In some conditions, microwave power increases higher compared to operating watts. such as a microwave oven with 1000 watts that uses 1800 watts of startup power
Startup Amps and Running Amps Differences
- Startup wattage: Startup amp shows the peak current that flows in the microwave at the starting time.
- While running, an ampere shows that there is steady current flow through the microwave at the starting time.
Can a microwave operate on a 15 amp circuit or a 20-amp circuit?
- According to the wattage value, microwaves operate on 15 amp and 20 amp circuits. microwaves of 1200 watts, operated on a 15 amp circuit. A microwave with a rating of more than 1200 watts is best to use a 20 amp circuit.
- Measure the total number of appliances for finding accurate circuit to use for the microwave. The circuit is used for microwave. A 120-volt grounded branch circuit has 3-prong grounding.
Does a Microwave uses certain Circuit?
- Microwaves need high energy for heating food. So it needed certain conditions for operating.
Electrical Code for Oven
- The National Electrical Code gives details for home wiring. It is referred to that a 20 amp circuit is employed for microwaves. During operation, a microwave uses high power. if it operates with other circuit faults or overloading occurs.
- Suppose you are using the oven and toaster at the same time. If both are working on the same circuit breaker, it will trip. since the shared circuit is overloaded. As a result, overloaded wiring becomes hot and results in a fire hazard. so electrical codes are used to avoid any damage
Use the right circuit breaker.
- There are different microwave ovens used, and each comes with a certain power level and size. Small microwaves operate with low current. Larger microwaves need high power.
- Accurate circuit breaker use according to microwave power requirements. 15 amp circuits are preferred for 1200-watt microwaves. but not the best to use. A 20 amp circuit is normally preferred for larger microwaves. The small breaker trips quickly if the oven uses more than 15 amps of current.
- Wiring also plays a role for circuit working. 20 amp circuit 12-gauge wiring system. This wire has features to handle high current. if thin wire is used, it causes overheating and results in voltage losses. that affects microwaves and kitchen devices.
- Before employing a shared circuit, get an idea of the microwave amp rating. If there is high current flow, then the handling capacity breaker will trip.
- So use a certain circuit that helps to save other devices and make the microwave work in the proper way.
Factor affecting Microwave’s Amp
Each microwave uses a different current and has a different watt rating. Some factors for ampere are as
Power required for cooking
- Microwaves come with variable power settings and use low current at low mode, regardless of how much time is taken for cooking.
Supply Voltage
- When the voltage reduces, especially for heavy loads, the current increases to maintain the wattage. that affects the microwave and power supply.
Efficiency
- Older microwave units were less effective and needed high current for generating the required cooking power. Advanced inverter-operated microwaves are effective and get high currents.
Ambient Temperature
- In cold conditions, microwaves get a high starting current since internal components need heating to get the required temperature.
Cable used in microwave ovens
3 Conductor Power Cord
- Microwave ovens come with different cables in their structure. First of all, it has a three-prong plug and a 3-conductor power cord that can bear 13 to 15 amps.
High-voltage cable
- The microwave comes with a high-voltage cable internally connected with the secondary coil of the HV transformer with a magnetron for generating microwaves. This cable carries high voltage, about 2000 to 5000 volts, so it needs proper insulation.
PVC-insulated wires
- The wiring circuit of the oven uses small-gauge, color-coded PVC wire connected with the inner parts of the oven like fans, motors, etc. These smaller-gauge wires are in the ampere rating of 18 AWG to 22 AWG. This inner wire also comes with thermal sensor wires.
Ground wiring
- In houses, ground wire is used with a rating of 14/2 or 12/2 that is taken out from the electrical outlet and has NM-B size.
FAQ
How Many Amps Are Needed for 1000-Watt Microwave Use?
- For 1000-watt microwaves, 8.3 amperes are required for a 120-volt outlet.
Can a microwave operate on a 15-amp circuit?
- Yes, normally microwaves’ rating is about 1000 watts, so they can easily work on a 15 amp circuit. while a 1500-watt microwave uses 20-amp circuits.
What breaker size is used for a 1500-watt microwave?
- 1500-watt microwaves use a 20-amp breaker.
What voltage is needed for microwave use in the U.S.A.?
- 120V is used in households in the USA, and some commercial models use 220V.
What wire size should I use for a microwave?
- • A microwave of 1000 watts employs 14-gauge wire, and high wattage uses 12-gauge wire.
How to Find Out How Many Amps a Microwave Uses?
- You can check through the data sheet of the oven and can get help from this formula.
Amps = Watts/ Volts
1000W/ 120V = 8.33A)
