What are the products of the intelligent high current system fault grounding wire selection device H

The high-current system can be tripped directly, and there is no need to select the line.

The line selection device is used for small current systems.

When the system has a grounding fault, the arc suppression device can play an ideal role in automatic tracking and compensation, so as to protect the operation safety of the user's power supply system first, and then select the line for the single-phase grounding fault line.

In order to ensure the safety of the power supply system, the arc suppression device will generally be in a working state that is close to fully compensating the capacitive current. Therefore, after compensation, the amplitude of the zero sequence current collected by the zero sequence current transformer in the fault line will be very small, even less than the capacitance current value collected by the non-fault mutual transformer that flows normally, so the grounding line selection judgment can not be analyzed according to the correct fundamental waveform component, but can only use the fifth harmonic or other waveform components, but the components of these waveforms are very unstable and are greatly affected by interference, so it is likely to cause misjudgment.

After the high-current grounding device is put in, the resistive current of the fault line is not compensated, and the first-line signal is added, which is conducive to fault line selection. This greatly improves the reliability and safety of power supply, and optimizes the operation mode of neutral grounding. Moreover, the device has strong adaptability, and the user does not need to replace the previously installed feeder cabinet zero sequence transformer, saving costs.

Compared with other line selection methods, the accuracy of the line selection method of high-current grounding device is extremely high; After the high-current grounding device is put into operation, the current generated to the ground is the active current, and the difference between the zero sequence current signal between the grounding line and the normal line in the time of resistance input (a few cycle times can be) is quite significant, and the accuracy of line selection can reach 100%, and the high-resistance grounding, metallic grounding and bus grounding can be accurately identified. Faulty lines can be tripped as needed.

What does it mean that the air conditioning chiller has two controls, three controls, and four controls. How does it work? Problems in the science and engineering of household appliances.

According to your description, the second control refers to the two pipes of the chiller back and forth, and the cold and hot functions can only be used in time, and the fourth control is two sets of back and forth pipes, and the cold and hot can work at the same time. The three controls refer to the hot and cold shared return pipes.

There are very few places in China that need to be cooled and heated, except in places with very high requirements for environmental control, such as five-star hotels. Moreover, the operation of the four controls often becomes offset by cold and heat, which is a waste of energy. There are more four controls in the United States.

There is no such mandatory provision.

If you buy a mobile phone at home, you can't replace it after repairing it several times. The air conditioner is much more complicated than the disassembly and installation of a mobile phone, and it is impossible to say that the machine can be replaced after several repairs.

It is only possible to replace the air conditioner when there is a major failure that cannot be repaired due to the manufacturer's responsibility, and the user strongly requests to replace the machine.

Can a ninety kilowatt generator drive a thirty-seven kilowatt motor? How should it be calculated, and who will be thanked for helping. Household appliances in science and engineering.

According to your description, 37 and 90*. So your engine can drive stable work. And your motor counts the efficiency and power factor, and the active and reactive power add together.

Of course, no problem.

1. The secondary discipline of 081100 Control Engineering and Control Science of East China University of Science and Technology is 081104 pattern recognition and intelligent system.

Fault detection is only one of the eight research directions, not a secondary discipline. 081100 Control Engineering and Control Science includes a total of 4 sub-disciplines.