1. Basic concepts

The fire pump motor is a device that converts electrical energy into mechanical energy. Its main function is to drive the impeller of the fire pump to rotate, so that the water can obtain energy and achieve the purpose of conveying fire water. It is usually installed on one side of the fire pump and connected to the shaft of the fire pump through a coupling or other connection methods.

2. Main classification

Classification by power supply type

（1） AC motor:

This is the most common type of fire pump motor. It uses an AC power supply, such as a three-phase AC 380V power supply (common in my country’s industrial and most fire protection facilities). Its advantages are simple structure, high reliability and easy maintenance. The three-phase AC motor generates a rotating magnetic field through the stator winding to drive the rotor to rotate.

For example, in a general building fire protection system, the asynchronous AC motor used can stably drive the fire pump and supply water in time when a fire occurs.

（2）DC motor:

It is less used than AC motors. DC motors require DC power supply. Its advantages are good speed regulation performance and can accurately control the speed of the motor. However, its structure is complex, the cost is high, and it requires matching DC power supply equipment. Usually used in special fire pump systems that require extremely high motor speed control, such as fire protection systems in some scientific research laboratories or special industrial sites.

Classification by motor protection level

（1）IP (Ingress Protection) 23 motor:

This motor can prevent solid foreign objects with a diameter greater than 12mm from entering the motor, and at the same time protect against angle splashing. It is suitable for fire pump rooms with relatively good indoor environments, and can work normally without a lot of dust and water splashing.

（2）IP 54 motor:

It can prevent dust from entering (it cannot completely prevent dust from entering, but the amount of dust that enters will not affect the normal operation of the motor), and at the same time protect against splashing water from any direction. This is a more commonly used protection level, which can meet the requirements in most fire pump application scenarios, whether it is indoor or semi-open fire pump room.

（3）IP55 motor:

The protection level is higher, which can prevent dust from entering and protect against water spraying from any direction. It is suitable for harsh environments that may be subject to water splashing, such as fire pump rooms near the sea or flood-prone areas.