Due to the inherent hysteresis of ferromagnetic materials, residual magnetic remanence will remain in the iron core after the operation of the voltage ratio and DC resistance measurement of the power transformer. Because of the existence of remanent magnetism, when the transformer is put into operat

What is the starting current and starting torque of the motor when the inverter is used? The frequency and voltage are increased with the speed of the motor, and the starting current is limited to 150% rated current (125 / 200 according to the type of machine). When starting directly with power freq

When the motor is driven by a power frequency power supply, the voltage decreases and the current increases; for the inverter drive, if the voltage also drops when the frequency drops, does the current increase? When the frequency drops (low speed), if the output is the same power, the current incre

What is the difference between voltage and current? The main circuit of the converter can be divided into two types: the voltage mode is to convert the DC of the voltage source into the AC converter, and the filter of the DC loop is the capacitance. Current mode is a converter that converts the curr

What is a converter? Frequency converter is a power control device which converts the power frequency power supply to another frequency by using the on-off action of the power semiconductor device. What is the difference between PWM and PAM? PWM is the abbreviation of Pulse Width Modulation, which c

The expansion of the capacitor shell in operation is due to the dissociation of the insulating material inside the capacitor, the breakdown of gas or the breakdown of some elements into the discharge of the shell, etc., which increases the internal pressure of the sealed shell of the capacitor. Caus

(1) The relevant capacitors should be tested and checked, and the reasons should not be found out, and the electric power is not allowed to be forcibly transmitted after the fuse is replaced;(2) Pay attention to the standard of fuse installation and select the fuse with qualified quality;(3) The fus

(1) Fuse fuses caused by internal faults of capacitors;(2) Non-standard installation of capacitor fuses or poor fuse quality, resulting in overheated fuse breaking;(3) Unreasonable selection of capacitor fuse (4) Overcurrent caused by high harmonic current in power grid leads to fuse breakage.

With the digital multimeter check, the digital multimeter is set to the appropriate resistor file, the red meter pen and the black meter pen contact the two poles of the measured capacitor respectively. At this point, the display value will gradually increase from 000 until the overflow symbol "1" i

An index multimeter can also be used to measure the capacitance of a digital meter. If you use an index multimeter, you usually use the R × 1K file to connect the pen to the two poles of the capacitance. The multimeter pointer wobbles and slowly recovers to or near zero. Such capacitors are good. Th