How To Measure The Starting Current Of A Motor?
The starting current refers to the inrush current of the electrical equipment (inductive load) when it is just started. It is the amount of current change from the moment when the motor or inductive load is energized to the short time when the operation is stable. This current is generally 4-7 times the rated current. In order to For the safe operation of the line and the normal operation of other electrical equipment, high-power motors must be equipped with starting equipment to reduce the starting current.
The process of starting the motor is a dynamic process. If Bulletproof motor wants to test accurately in the actual test process, it is generally completed by a waveform recorder with a high sampling rate or a test instrument with waveform recording function. Record the measured power with a high sampling rate test instrument and draw a transient waveform or trend curve. Generally, the following test methods are used:
Use an oscilloscope to measure – install a current sensor with a relatively large ratio (which can be selected according to the power of the motor or the parameters provided by the manufacturer) in the motor starting circuit, and the secondary winding of the current sensor is connected to the oscilloscope to complete the measurement.
Use the fault recorder to measure – install a current sensor in the motor starting circuit, connect the secondary winding of the current sensor to the fault recorder, and start the recorder during the motor startup process to measure.
Use a portable power quality analyzer to measure – a current sensor is installed in the motor starting circuit, and the secondary winding of the current sensor is connected to a portable power quality analyzer to measure during the motor starting process.
Test with a high-end motor test system – by setting parameters such as the dynamometer sensor ratio and synchronization source, the starting current can be effectively tested.
Use a power analyzer to measure – Bulletproof motor power analyzer is a general-purpose test instrument and an essential component of a modern motor test bench, which can accurately test various parameters of the motor with high precision.
