Before reading this section, a basic knowledge of electricity is helpful, so you might want to review the chapter on basic electricity. After all, the motor is the device that converts electricity into mechanical power.
Motors, like the pumps they drive, are rated by horsepower, usually in the pool and spa word as ½, ¾, 1.0, 1.5 and 2.0 horsepower. Commercial swimming pool service installations might use higher rated systems, but these are the most common.
Electricity flows through the motor windings, which are thin strands of coiled copper or aluminum wire. The windings magnetize the iron stator. If you paid attention in your first grade science class, you recall that opposite poles of a magnet attract each other, but like poles repel. Using this concept, the rotor spins, turning the shaft.
Some designs employ one set of windings for the startup phase where greater turning power (torque) is needed and another set for normal running.
The shaft rides on ball bearings at each end. A build-in fan cools the windings because some of the electrical energy is lost as heat. The caps on each end of the motor housing are called end bells. A starting switch is mounted on one end with a small removable panel for connection and maintenance access
This is where you will also find the thermal overload protector. This heat-sensitive switch is like a small circuit breaker. If it gets too hot, it restarts the pump.
Pump motors used in pool and spa operations have many variations in design and installation.
Smaller pump motors (three horsepower or less) are usually compact, open designs. They have an extended shaft that allows the pump adapter to be mounted directly to the housing. Larger motors follow the design standards of the National Electrical Manufacturer’s Association (NEMA). Quite often these motors are of the frame-mounted design requiring a coupling pump.
Motors used on pools or spas are normally 115/230 volt, single phase, or 230/460 volt 3 phase AC. Motors at 5 horsepower and above are usually 200 volt AC or 230.460 volt AC. The 230/460 volt AC is obsolete, and the pool operators should be aware of this for replacement purposes.
The pool operator should look to outside Pool Companies Miami professionals, licensed help when servicing or repairing motors. Most motors are capable of handling two voltages, and the motor terminals must be connected properly to the available voltage supply.
The motor name plate provides the necessary replacement information, and this data should be part of the pool service Miami professional files. With the availability of digital cameras today, it is easy to take a picture of the motor name plate for file purposes. This should be done while the motor is relatively new and the name plate is easily readable.