Planning for the electrical connections of high-powered devices, like a 5000 watt equipment, starts from knowing the current. It’s crucial because it determines the wire gauge necessary for the appliance to operate safely and effectively.
How many amps is 5000 watts? We get 416.7 amps at 12 volts and 208.3 amps at 24 volts in a DC circuit, and at least 41.7 amps at 120 volts and 20.8 amps at 240 volts in a single-phase AC circuit.
Table of Contents
Calculate Amps, Watts and Volts
Electric power is generally defined as
\[ \text{Power (watts)} = \text{Voltage (volts)} \times \text{Current (amps)} \]
From this definition of electric power, we can estimate the current drawn by a device as:
\[ \text{Current (amps)} = \frac{\text{Power (watts)}}{\text{Voltage (volts)}} \]
Take note that the unit of current of 1 amp = watts/volts.
This relationship is true for DC circuits, like the 12 volt circuit used in cars. For example, if we want to know the current drawn by an amplifier rated at 4000 watts connected to a 12 volt battery (assuming the battery is at 13.6 volts when running), then its estimated current draw will be
\[ \text{Current (amps)} = \frac{\text{Power (watts)}}{\text{Voltage (volts)}} = \frac{4000 \, \text{watts}}{13.6 \, \text{volts}} = 294 \, \text{amps} \]
AC circuit
However, current flowing to appliances in an AC circuit may need to consider the power factor of the appliance or the power delivery system. The power factor for a single phase AC circuit is the ratio of the actual power consumption of the appliance or electrical system and its apparent power rating, and is a value ranging from 0 to 1:
\[ \text{Power Factor (PF)} = \frac{\text{Actual power (watts)}}{\text{Apparent power (volt}\cdot\text{amp)}} \]
\[ \text{Apparent power (volt$\cdot$amp)} = \frac{\text{Actual power (watts)}}{\text{Power Factor (PF)}} \]
To get the expected current that will be drawn by the machine, we can expand apparent power using the definition of power earlier:
\[ \text{Voltage (volts)} \times \text{Current (amps)} = \frac{\text{Actual power (watts)}}{\text{Power Factor (PF)}} \]
\[ \text{Current (amps)} = \frac{\text{Actual power (watts)} \times \text{Power Factor [PF]}}{\text{Voltage (volts)}} \]
The higher the power rating, the more energy is used to do useful work and less energy is wasted. Thus, an appliance may draw more current than what it is actually rated.
For instance, if an induction heater oven has a power rating of 3000 watts and a power factor of 0.85 plugged at 220 volts, its current draw based on its rating of 3000 watts will be:
\[ \text{Current (amps)} = \frac{\text{Power (watts)}}{\text{Voltage (volts)}} = \frac{3000 \, \text{watts}}{220 \, \text{volts}} = 13.6 \, \text{amps} \]
However, because it only has a power factor of 0.85 watts, then current draw is expected to be
\[ \text{Current (amps)} = \frac{\text{Actual power (watts)}}{\text{Power Factor [PF]}\times\text{Voltage (volts)}} = \frac{3000 \text{ watts}}{0.85 \times 220 \text{ volts}} = 16 \text{ amps} \]
Interestingly, resistive loads like resistive electric heaters and incandescent lights may have a power factor of 1. However, inductive loads and motors may have a power factor of less than 1.
The current calculation with the power factor for a 3-phase AC supply is slightly different:
\[ \text{Current (amps)} = \frac{\text{Actual power (watts)}}{\sqrt{3} \times \text{Power Factor (PF)} \times \text{Voltage (volts)}} \]
While 3 phase power is very good for commercial use, its uncommon to find these circuits with 208 volts or up to 600 volts in residences, so we won’t cover it here. A wattage calculator and an amperage calculator for 3 phase power can be found online, though.
Current at Different Voltage and Power Factors
A quick use of the equations will convert 5000 watts to amps. But, for convenience, here is a handy table that compares the current drawn at different voltages and power factors to easily show how to convert watts to amps for up to 6000 watts.
Power (watts) | DC | AC single phase | ||||||
12 volts | 24 volts | 120 volts | 240 volts | |||||
– | – | PF = 1 | PF = 0.85 | PF = 0.5 | PF = 1 | PF = 0.85 | PF = 0.5 | |
1000 | 83.3 | 41.7 | 8.3 | 9.8 | 16.7 | 4.2 | 4.9 | 8.3 |
1500 | 125.0 | 62.5 | 12.5 | 14.7 | 25.0 | 6.3 | 7.4 | 12.5 |
2000 | 166.7 | 83.3 | 16.7 | 19.6 | 33.3 | 8.3 | 9.8 | 16.7 |
2500 | 208.3 | 104.2 | 20.8 | 24.5 | 41.7 | 10.4 | 12.3 | 20.8 |
3000 | 250.0 | 125.0 | 25.0 | 29.4 | 50.0 | 12.5 | 14.7 | 25.0 |
3500 | 291.7 | 145.8 | 29.2 | 34.3 | 58.3 | 14.6 | 17.2 | 29.2 |
4000 | 333.3 | 166.7 | 33.3 | 39.2 | 66.7 | 16.7 | 19.6 | 33.3 |
4500 | 375.0 | 187.5 | 37.5 | 44.1 | 75.0 | 18.8 | 22.1 | 37.5 |
5000 | 416.7 | 208.3 | 41.7 | 49.0 | 83.3 | 20.8 | 24.5 | 41.7 |
5500 | 458.3 | 229.2 | 45.8 | 53.9 | 91.7 | 22.9 | 27.0 | 45.8 |
6000 | 500.0 | 250.0 | 50.0 | 58.8 | 100.0 | 25.0 | 29.4 | 50.0 |
Related: How Many Amps to Run 2000 Watts
Conclusion
So, how many amps is 5000 watts? The current draw of a 5000 watt device depends primarily on the voltage and kind of circuit it connects to. For DC circuits, it can reach from 208 amps up to 417 amps. For AC single phase circuits, it can range from 20.8 amps to 83.3 amps, depending on the power factor.
Knowing the right current draw of the device will help prepare the right electrical connections to safely deliver electricity to the 5000 watt appliance. Just make sure you consult a certified electrician for this project.
I am Edwin Jones, in charge of designing content for Galvinpower. I aspire to use my experiences in marketing to create reliable and necessary information to help our readers. It has been fun to work with Andrew and apply his incredible knowledge to our content.