Motor Temprature Rise Causes

Motor Temprature Rise Causes:

• Slowly developing temperature rise:
• Insuffi cient cooling
• High ambient temperature
• High altitude operation
• High liquid temperature
• Too high viscosity of the pumping liquid
• Frequent starts
• Too big load inertia
(not common for pumps)

• Quickly developing temperature rises:
• Locked rotor
• Phase breakage

To protect a circuit against overloads and short circuits, a circuit protective device must determine when one of these fault conditions occurs. It must then automatically disconnect the circuit from the power source. A fuse is the simplest device for accomplishing these two functions. Normally fuses are built together by means of a safety switch, which can switch off the
circuit. On the following pages, we will present three types of fuses as to their function and to where they are used: Fusible safety switch, “quick-acting” fuse and “time-lag” fuse.