# What causes an electric motor to draw more current?

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## What is the reason of motor taking high current?

Probable causes of high current with load include mechanical overload, excessively high magnetic flux densities and, less frequently, an open rotor. An error in winding data that results in lower-than-design-level magnetic flux also can cause high current with load.

## What determines how much current a motor draws?

Calculate the amps used by dividing the wattage by the voltage. For example a 500-watt motor — running on 50 volts — will draw 10 amps. A motor with the same wattage — running on 20 volts — will use 25 amps. This is the theoretical number of amps used by the motor.

## What causes amps to increase?

Because voltage equals the amperage multiplied by the resistance in a circuit, if the voltage remains constant and the resistance is dropped, the amperage across the circuit must increase. … If the circuit’s resistance remains unchanged, the amperage in a circuit can be increased by increasing the voltage.

## Do electric motors draw more current as they age?

RE: Increasing current requirements with age

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Most of the motors are around 1.2A – 1.3A when they are new. They are typically 1.42A – 1.54A after being rebuilt.

## What causes excessive current draw?

Overcurrent is just like it sounds: It’s an excess of current—or amperage—in an electrical circuit. … An overcurrent can be caused by overloading the circuit or by a short circuit, a ground fault, or an arc fault. Circuit breakers and fuses protect circuit wiring from damage caused by overcurrent.

## Why does current increase when motor load increases?

If the mechanical load increases, the rotor stops a bit (since it’s harder for the rotor to rotate a heavier load), which decreases the counter-EMF. This reduction in the counter-EMF thus increases the current in the coil, and so the power needed from the external voltage source.

## What determines current draw?

Divide the watts of a given electrical item by the total number of volts available from the electric outlet to calculate amperage draw. The amount of current flowing through the wire is measured in amperes, or amps. The equivalent of available electricity at the power source is voltage, or volts.

## How much current does an electric motor need?

acceptable for a short-period: 20 – 120% acceptable for operating: 50 – 100% optimum efficiency: 60 – 80%

## How do you reduce the amperage of an engine?

According to Ohms Law (I=E/R or Amps=Volts/Ohms) if the voltage in the circuit remains constant and the resistance is increased, the current should decrease. Try adding resistance to the circuit to lower the current output.

## What happens if the amps are too high?

Amperage Provided versus Amperage Required

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Device may fail, may run or charge slowly, power supply may overheat, may damage the device being charged — all depending on the magnitude of the difference. The amperage provided by your charger must match or exceed what the device being charged requires.

## What happens to current when voltage increases?

Ohm’s law states that the electrical current (I) flowing in an circuit is proportional to the voltage (V) and inversely proportional to the resistance (R). Therefore, if the voltage is increased, the current will increase provided the resistance of the circuit does not change.