Tres de los problemas más comunes en los motores trifásicos por los que somos consultados son:

1. “El motor toma mucha corriente en vacío”
2. “La corriente en las tres líneas no está balanceada”
3. “ El motor trabaja caliente”

Incluso si nunca te has enfrentado a uno de estos problemas, sigue leyendo porque es casi inevitable que lo hagas y querrás saber qué hacer al respecto.

Three of the most common three-phase motor problems we receive inquiries about are:

1. “The motor is drawing high no-load current.”
2. “The current of the three line leads is not balanced.”
3. “The motor is running hot.”

Even if you have never faced one of these issues, read on because it is almost inevitable that you will, and you will want to know what to do about it.

Three of the most common motor problem calls received from members by EASA's Technical Support Department are:

• "The motor is drawing high no-load current."
• "The current of the three line leads is not balanced."
• "The motor is running hot."

If you have ever faced one or more of these issues, and it's almost certain you have, read on.

How much no-load current should I expect when testing a motor? Many of us expect a motor to draw approximately one-third of rated current, when operating from rated voltage on our test panel. That is a good rule of thumb — most of the time.

When a motor is test run without a load after it has been rewound, one of the questions we are asked is why the amps are too high, even higher than the nameplate full load. Here are a few of the common factors to consider.

Typically, motor currents of interest are the no-load current, full load current, service factor current, and starting (or in-rush) current. You will know the full load current from the nameplate, and you can calculate the starting current from the Code Letter on the nameplate. Service factor current may or may not be on the nameplate. The no-load current will not be shown on the nameplate. It is possible to obtain the value from the manufacturer, but not always. The no-load current is an important benchmark, and once it is established, you can estimate the load on the motor at any time.