Hydraulic power unit motor has both kinds:AC motor and DC motor.
Usually AC motor has both kinds motors,three-phase motor and single-phase motor,it is according to the user’s need to choose,which was divided into ordinary AC motor and and special oil pump motor.Ordinary AC motor can be achieve the long time work duty, and special oil pump motor apply only in short-time work system.
It is according to the structure of the motor,the motor is with fan and fan-less.It is according to the using occasions,the motor has common motor and explosion-proof motors.The explosion-proof motor currently only the phase voltage 380V motor, explosion-proof unit does not apply in downhole operation equipment.
DC motor has short-time work system and long-time work system, the power unit commonly used short-time working motor,but also according to the actual need to choose a brush motor delay or brush-less motor to extend the working time of a motor
Some user with special voltage, frequency, degree of protection required motor requires special order.
Since the DC operating current is large, generally using electromagnetic starter switch auxiliary starting, motor and switch wiring can be found in the following diagram
Single-phase AC motor is very impact by starting voltage, so when in use must be strictly controlled by line specifications and its line length, to reduce the loss of line voltage.
To ensure the normal operation of DC motors and electromagnetic starter switch, the input voltage should not be less than 10% of rated voltage.
The use of various types of electronic control valve voltage reference to this requirement.
DC motor of a shaft end is rotated to a normally clockwise, and AC motor a shaft end is rotated to the general according to the oil pump rotation to the different changes, depending on the motor fan cover has a rotation flag.