ABB
12
ABB | Motors and Generators
| Synchronous motors
Effective and uniform cooling of the complete motor
With a wide range of cooling methods available, the
optimum system can be selected for the motor’s operating
and environmental conditions.
Whichever method is chosen,
it will provide effective cooling of the complete motor.
The three most commonly used cooling arrangements
are air-to-water, air-to-air and open air.
Air-to-water closed circuit cooling
The cooling air circulates in a closed circuit through the active
parts of the motor and then through an air-to-water heat
exchanger. This cooling method is especially recommended
if the cooling water is located nearby. This configuration is an
ideal solution for situations where closed circuit cooling is
required due to installation outdoors, installation in a hazardous
area, or whenever the quality of the surrounding air is not
otherwise suitable for direct cooling. It is also ideal for
installations in machine rooms with limited ventilation,
such as on board ships or in pumping stations which are
fully enclosed.
Air-to-air closed circuit cooling
The cooling air circulates in a closed circuit through the active
parts of the motor and through an air-to-air heat exchanger.
This solution is generally used in situations where a closed
circuit cooling system – such as air-to-water cooling – is
required but water is not readily available. This cooling
arrangement requires an additional shaft-mounted or separate
electric fan to ensure sufficient air flow through the cooler.
Open air cooling
Open air cooling can be used where the air in the immediate
environment is relatively clean and there is adequate air
circulation. The cooling air is typically drawn in through filters,
passed through the active parts of the motor, and then
exhausted back to the environment. If the machine room
ventilation system cannot compensate for the temperature
gradient, the motor air outlet can be ducted to exhaust the
air outdoors.
Enclosure protection classes
The motor enclosures feature protection in classes IP23,
IP44, IP54 and IP55 (totally enclosed), or equivalent NEMA
protection classes. Motors are also available for hazardous
areas in accordance with IEC/ATEX or NEC regulations
(non-sparking or pressurized construction).
An open air cooled motor (IC0A1) with drip
proof protection (IP23)
A totally enclosed motor (IP54) using
an air-to-water heat exchanger (IC8A1W7)
A totally enclosed motor (IP54) using
an air-to-air heat exchanger (IC6A1A6)