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## How do you find the mechanical output of a motor?

Mechanical power is typically defined as **kilowatts or horsepower**, with one W equaling 1 Joule/sec or 1 Nm/sec. Figure 9: Mechanical power measurements in watts are defined as two times Pi times the rotating speed (rpm) divided by 60 times the torque (Newton-Meter). Horsepower is the work done per unit of time.

## How do you test electric motor power?

To test your motor for short to ground, you’ll need to set the **multimeter to ohms and disconnect the motor from its power source**. Then inspect each wire and look for infinite readings. Alternatively, if you get a reading of 0, you might have a cable issue.

## How do you measure the power of a 3 phase motor?

Calculate three-phase motor power consumption by multiplying amps by volts by the square root of three (W = AV(sqrt 3). For example, if the motor is drawing 30 amps at 250 volts, you have 30 x 250 x sqrt 3 (about 1.73) = 12,975 watts).

## Why would an electric motor stop working?

Stressful mechanical, environmental, and **electrical operating** conditions can all cause electric motor failure. Electrical failures are winding failures caused by an open contactor, bad connection, blown fuse, excessive heat, electrical overload, or broken power lines.

## Should an electric motor have continuity?

The windings (all three in a three-phase motor) should read low but not zero ohms. … It will usually be low enough (under 30 Ω) for the audible continuity indicator to sound. For proper motor operation, all windings must have **megohm readings to ground**, i.e. to the motor enclosure.

## How many ohms should a motor read?

With a multimeter, measure the resistance between motor frame (body) and earth. A good motor should read **less than 0.5 ohms**. Any value greater 0.5 ohms indicate trouble with the motor.

## How many amps does a motor draw?

AMP DRAW BASED ON HORSEPOWER

HP | 1 Phase Amps | 3 Phase Amps |
---|---|---|

115 volt | 230 volt | |

1 | 16 |
4.2 |

1-1/2 | 20 | 6 |

2 | 24 | 6.8 |

## How many amps does a 12v motor use?

When calculating the current draw in amps with a 12 VDC Motor you can use the following guidelines: **0.1 HP = 8 amperes**. **0.2 HP = 17 amperes**. **0.5 HP = 42 amperes**.

## How many amps is a 3 phase?

If your calculator doesn’t have a square root function, use 1.73 as an approximation of the square root of 3. For example, a three phase circuit using 25,000 watts of power and a line voltage of 250 will have a current flow of 25,000/(250 x 1.73), which is equal to **57.80 amperes**.

## What is the formula for active power?

Active power: **P = V x Ia (kW)** Reactive power: Q = V x Ir (kvar)

## How do I calculate power?

**Power is equal to work divided by time**. In this example, P = 9000 J /60 s = 150 W . You can also use our power calculator to find work – simply insert the values of power and time.