Pumps are general rotating machines whose operating power comes from motors. The types of pumps include sealless magnetic pumps, mechanical seal pumps or other forms of centrifugal pumps, all of which must be connected to a motor to achieve the purpose of fluid transportation.
Motors can be divided into general motors, variable frequency motors and explosion-proof motors. The specifications of the motors also vary depending on the purpose and use environment. The following introduces how to select a suitable motor according to the requirements when using a pump.
For different purposes, motor specifications can be determined, such as number of poles (Pole), speed (RPM), frequency (Hz), voltage (V), installation location (install location), protection level (IP Rating), Energy efficiency index (energy efficiency index), to determine the selected model.
Number of Poles (Pole), Speed (RPM), Frequency (Hz)
The number of poles (Pole) represents the number of magnetic poles of the motor's stator magnetic field. Depending on the connection form of the stator coil windings, different numbers of poles of the stator magnetic field can be generated. The number of poles of the motor will affect the speed of the motor.
Revolutions Per Minute (RPM) means revolutions per minute. For example, the rotation speed of a motor is 3,600 RPM, which means the motor can rotate 3,600 times per minute.
Frequency (Hz) refers to the frequency of alternating current in the power grid. Frequency is the rate at which the current changes direction per second. The international unit of measurement is Hz. Generally speaking, countries use 50Hz or 60Hz frequency.
The formula of rotational speed: rotational speed (RPM) = frequency (Hz) x 60 (sec/min) x 2 ÷ number of poles
So under normal circumstances, when the frequency is 60Hz, 2P turns to 3600 rpm, 4P Turn to 1800rpm, 6P to 1200rpm, and so on. It can be seen from the formula that the number of poles, frequency and speed are closely related to each other.
Voltage (V)
The voltage is proportional to the motor speed, that is to say, the higher the input voltage, the faster the motor speed; the lower the input voltage, the slower the motor speed.
Protection Level (Protection) & Installation Location (Install Location)
Protection level (IP level) is usually marked by IPXX, such as IP54, IP55, IP56, etc. The first number after it represents the protection ability against solid foreign matter contact and intrusion, and the second number represents the resistance against liquid penetration. Protective ability.
The motor can be installed indoors or outdoors based on the IP rating, whether it can withstand wind, sun, rain, client operating requirements, noise issues and other conditions.
Energy Efficiency Index
Motor rated efficiency (International Efficiency) is defined by the International Electrotechnical Commission (IEC). The energy efficiency levels are divided into IE1, IE2, IE3, and IE4. The larger the number, the better the efficiency and the more power saving.
The above are the relevant specifications that must be referred to when selecting motors. Next, the differences and applications of general motors, variable frequency motors and explosion-proof motors will be introduced.
The best solution for chemical fluid transportation》PTCXPUMP sealless magnetic pump / INNOMAG Lined Sealless Magnetic Pump
