Overload Protection for 3-Phase Motors

Several conditions can cause a motor to become overloaded. Examples include a bound pump, or a high or low voltage condition. When a motor becomes overloaded, the current (amps) increase, and can reach levels damaging to the motor. Therefore, a motor must be protected from an overload condition, and this is the job of the overload protector, sometimes just called the “overload”.

In a recent edition of the Franklin AID, we discussed overload protection in Franklin Electric single-phase motors. These motors contain “built-in” overload protection, either in the motor itself or in the Franklin Control Box, depending on the horsepower rating. In this issue, we will discuss 3-phase motor protection. Continue reading