TEFC “Totally Enclosed Fan Cooled": Prevents the free exchange of air between the inside and outside of the frame, but does not make the frame completely air tight. A fan is attached to the shaft and pushes air over the frame during its operation to help in the cooling process. Totally enclosed motors are suitable for use in humid environments. The motor is dust tight and has a moderate water seal as well.
Designed to withstand high pressure wash-downs or other high humidity or wet environments. This does not allow for the motor to be submerged.
For years, equipment downtime scene was common in the food and beverage plants. Many indoor enclosures require protection from excessive moisture generated from hose directed or splashing water (Washdown). Washdown duty motors are designed for use in food and beverages plants and other applications where motors are routinely exposed to washdown and contaminants (Chemicals, moisture, and humidity).
Washdown motor protect the motor internals (Stator windings, the stator assembly, rotor and shaft).
Inverter Rated Motor?
“Inverter Rated” motors are suitable for use with Variable Frequency Drives and can run at very slow speeds without overheating, also they are capable of withstanding higher voltage spikes without their insulation failing. For this reason, an inverter-Rated motor can be much more expensive than general purpose motors.
Inverter Rated 10:1 means that the slowest speed at which the motor is expected to operate.
If you have a 3,500-rpm motor (60hz) the slowest speed must be 350 rpm (3500/10 = 350)
What Do The NEMA Frame Sizes?
The National Electrical Manufacturers Association (NEMA) is a US Manufacturers Organization which actively promotes standardized product specifications for electrical apparatus. NEMA frame size refers to mounting including the frame, motor and shaft dimensions. Is commonly used in the industry to ensure that replacement parts will fit and be readily available, and that motors from different manufacturers will be interchangeable.
"C" Face (Flange)
This is the most popular type of face mounted motor is a type of flange used with close coupled pumps, speed reducers, and similar applications where the mounting holes in the flange are threaded to receive bolts. Normally the “C” flange is used where a pump or similar item is to be overhung on the motor. C flanges motors always have mounting holes in the face of the motor.