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How do you discharge high dc voltage capacitor?
When a capacitor is powered off in an energized circuit, the capacitor still stores a certain amount of electricity. When there are other loads or components in the circuit, they will slowly discharge, or they can be quickly discharged by short-circuiting with small resistors or wires (at low voltage). When the capacitor discharges, the two poles of the capacitor respectively carry a certain amount of charge, and the outside world and the capacitor form a closed loop (generally, the closed loop does not include a power supply). The excess electrons (negative charges) approach the positive electrode of the capacitor to form a current, so that the charges at both ends of the capacitor are neutralized. When the neutralization is completed, the electric field between the two electrodes of the capacitor disappears. However, this is in an ideal situation. The amount of terminal charge is exponentially neutralized towards zero, but not zero. Discharge requirements of capacitors After the capacitor is disconnected from the bus, it must be discharged through a discharge resistor or a special voltage transformer. Discharge should be performed between the lead wires of the capacitor and between the lead wires and the casing. The capacitor can be grounded after the capacitor is discharged. Before working on the capacitor, be sure to conduct a test discharge. This discharge is to place the discharge rod on the terminal of the lead wire of the capacitor for a period of time. Even if both sides of the capacitor device are grounded, in order to prevent residual charge on the capacitor, a test discharge must be performed, and each group of capacitors connected in parallel must be discharged. Special care should be taken when conducting inspection discharge of capacitors removed due to faults. Due to the damaged capacitor, the general grounding device may not function as a ground discharge due to a partial disconnection. If the capacitor device has an interlock device, it should be considered that only after the entire device is grounded, the small door of the capacitor bank protective fence can be opened. We're JYH HSU(JEC) Electronics Ltd (or Dongguan Zhixu Electronic Co., Ltd.), an electronic components manufacturer. You may google "JYH HSU" to find our website.
How does the output voltage of the VFD change if the DC bus voltage level is fixed?
The VFD outputs pulses at the DC bus voltage. Each pulse is from the DC bus and the voltage does not change. It is the average voltage that changes because the VFD changes the on and off times of these pulses. For a lower average ac voltage to the motor, the ON time is small and the OFF time is large. The VFD actually pulses about 4000 times per second, so the motor does not really know these are just lots of quick DC bus voltage pulses. To simulate an ac waveform, the VFD uses pulse-width modulation which means the pulse ON time at the peak of the simulated sinewave is longer, or fatter, than the pulses where the simulated sinewave is closer to 0 crossing.
Why the impedance of infinite bus bar is zero?
...because it is an infinite bus bar, meaning it can supply infinite current. By Ohm's law, since the voltage at the bus bar is fixed, to have infinite current, you must have a zero impedance.
What is an infinite bus bar?
A theoretical bus that can provide infinite amounts of current. This is often used in distribution level load studies - the distribution source bus is often modelled this way. The majority of voltage drop is due to the modelled distribution lines, and the step down transformers to the distribution bus often use load tap changers to keep the source voltage at the desired level anyway.It's a electrical term relating to power grids. See the Related Link below.
Control diagrame of a capacitor bank and why you use capacitor banks?
---- Capacitor banks used to improve power factor(lagging) of a circuit:: This is necessary since it causes saving in power and electricity bill in following ways: 1) As p.f rises, circuit currnt decreases and hence I2R losses reduce 2) Var consumption reduces There is no tool provided here to draw the ckt diagram:: U take on PFC(power factor correction bus), then connect switch fuse, then HRC fuse, then Contactor, then overload relay and finally the capacitor bank
What are difference between bus reactor and line reactor?
A bus reactors a devise installed in a bus to maintain system voltage when the load on the bus changes by releasing reactive power as usable power to bolster the voltage. A line reactor is placed in line at point of use or just after a transformer to maintain a stable amperage to the user, capacitor.
What are the difference between bus reactor and line reactor?
Bus reactors are the inductors that limit voltage transients between a couple sections of a bus or a couple separate buses. Line reactors are capacitor or user amperage stabilizers placed at points of usage or right before transformers.
What is PV bus?
In power systems, there are 3 types of buses: swing bus, load bus and voltage controlled bus. PV bus is another name for voltage controlled bus.
What passive components will help with terminating a SCSI bus?
capacitor
What is conditions need to sychronaising?
The generator voltage has to be the same as the bus voltage
What are the conditions for Synchronization of three phase alternator and bus bar?
voltage of incoming machine should be same as that of bus bar voltage
How is binary data put on a line of a bus in a computer?
By placing voltage on that line of the bus.
Where is the location of capacitor banks in the sub stations?
They can physically be located almost anywhere. Capacitor banks are typically attached to the bus in substations. Reactors are often tapped off lines.
Binary datda is put on a line of a bus by placing voltage on that line?
Data bus is used to transit data from one place to another by placing voltage. This indicates that data is traveling but voltage is used to hold the line and is not travelling.
What is usb bus power?
The Voltage at which the USB Drive works at.
How do you discharge high dc voltage capacitor?
When a capacitor is powered off in an energized circuit, the capacitor still stores a certain amount of electricity. When there are other loads or components in the circuit, they will slowly discharge, or they can be quickly discharged by short-circuiting with small resistors or wires (at low voltage). When the capacitor discharges, the two poles of the capacitor respectively carry a certain amount of charge, and the outside world and the capacitor form a closed loop (generally, the closed loop does not include a power supply). The excess electrons (negative charges) approach the positive electrode of the capacitor to form a current, so that the charges at both ends of the capacitor are neutralized. When the neutralization is completed, the electric field between the two electrodes of the capacitor disappears. However, this is in an ideal situation. The amount of terminal charge is exponentially neutralized towards zero, but not zero. Discharge requirements of capacitors After the capacitor is disconnected from the bus, it must be discharged through a discharge resistor or a special voltage transformer. Discharge should be performed between the lead wires of the capacitor and between the lead wires and the casing. The capacitor can be grounded after the capacitor is discharged. Before working on the capacitor, be sure to conduct a test discharge. This discharge is to place the discharge rod on the terminal of the lead wire of the capacitor for a period of time. Even if both sides of the capacitor device are grounded, in order to prevent residual charge on the capacitor, a test discharge must be performed, and each group of capacitors connected in parallel must be discharged. Special care should be taken when conducting inspection discharge of capacitors removed due to faults. Due to the damaged capacitor, the general grounding device may not function as a ground discharge due to a partial disconnection. If the capacitor device has an interlock device, it should be considered that only after the entire device is grounded, the small door of the capacitor bank protective fence can be opened. We're JYH HSU(JEC) Electronics Ltd (or Dongguan Zhixu Electronic Co., Ltd.), an electronic components manufacturer. You may google "JYH HSU" to find our website.
How do you increase voltage of distribution bus bar?
A hybrid grid mini-system
