Ask a friend who understands electricity to do a favor, and help a good person who learns electricit

The first thing to do is to determine if the leakage protector is normal. If you can use an electric pen (neon lamp and electronic together) along the trunking to measure it, pay special attention to the bend and the end of the line, and the leakage can be measured near the line. Pay attention to safety, try to minimize direct contact with wires and electrical appliances, if the whole section will be measured leakage, it is the line aging!

Is it off after a break time, and it will be protected as soon as it is opened after it is dropped.

Most of the time it is because a certain section of the line is aging, or you have some high-power electrical appliances at home, and the wires are heated and short-circuited after a while (old wires are often like this, and your home is very humid, and accidents are more likely to occur in rainy days).

It is recommended that you check whether there are high-power appliances turned on at home, and if the wiring at home is very old, it is best to update them all.

The situation you said is not leakage but leakage protector overload, you must use high-power appliances like induction cookers in your home, you can change to a 20 amp leakage protector.

Do not turn on high-power appliances at the same time.

The voltage of 2A remains the same, and the total resistance in the circuit will become smaller if it is changed from series to parallel, so the current can only become larger, which must be greater than 2A in series

Series connection: power supply voltage U=2*(R1+R2).

When connected in parallel, the resistance after parallel connection is r and = r1r2 (r1+r2), so the dry circuit current i = u r and = [2*(r1+r2)] [r1r2 (r1+r2)]=[2*(r1+r2) 2] r1r2

When r1=r2, there is a minimum value, then i minimum = [2*(r1+r2) 2] r1r2=[2*(r1+r1) 2] r1r1=8a

Rated power; 50%-100%;b;a;b;x;x;x;x;v;

Repeated Grounding: In a system where the neutral point is directly grounded, the grounding device is connected with a metal wire at one or more points of the zero trunk.

Working Grounding: In TN-C systems and TN-C-S systems, grounding is used to ensure that the circuit or equipment meets the requirements for operation.

Protective grounding: Grounding to prevent the metal shell of electrical installations, the frame of power distribution devices, and line towers from being energized and endangering the safety of people and equipment.

In AC circuits, the cosine of the phase difference ( ) between voltage and current is called the power factor.

By improving the power factor, the total current in the line and the capacity of the electrical components in the power supply system, such as transformers, electrical equipment, wires, etc., are reduced, so it not only reduces the investment cost, but also reduces the loss of its own electric energy; By ensuring good power factor, the voltage loss in the power supply system can be reduced, the load voltage can be more stable, and the quality of power can be improved. It can increase the margin of the system and tap the potential of power generation and power supply equipment.

i=(100*22+(40*20/;is the power factor of the fluorescent lamp.

Fuse wire selection 20a

The last problem, as with single-phase full-bridge rectification, is just two more diodes in the other phase, one for the positive and one for the negative.

p: Power.

u: Voltage. i: Current.

According to p = u * i: i = p up is measured in w (watts), u in v (volts), i in (amps) 1 amp = 1 watt 1 volt.

1kw=1000w, you have to calculate the current, don't forget to convert the unit clearly.

Voltage multiplied by current equals power Power divided by voltage is current.

Rubber shoes (rubber soled shoes) are not insulated shoes, and carbon black is added to the rubber, which has a certain conductivity. Who told you that galoshes are insulated shoes? Only insulated shoes that are marked as electrician insulated shoes can be called insulated shoes.

In the electrician training class, the teacher said that the electric person is the current rather than the voltage, this sentence is right, when we put our hands on the low-voltage power supply will not have an electric shock, this is a requirement, generally 36V below the safety voltage, the higher the voltage level, the smaller the current, the lower the voltage, the greater the current, the electricity you need to dance is the need for current, the low voltage to electricity you dance requires a lot of current, but the high voltage electricity to you dance, the current is very small.

To put it simply, this sentence is true, there must be an electric current through the human body to electrocute people, but not all, so if you touch a 500kv high-voltage electricity, you will be electrocuted even if you hang in the air, even if there is no current loop, the same electrocution of you, or for example, you touch the live wire with one hand, and all other places are insulated, you will still feel very electric, this according to the charge, according to the current and voltage can not solve the problem.

1. Now there is an office building and I want to run the main line. There are 6 air conditioners inside, 2 air conditioners for 3 horses, lighting, computers, printers, water dispensers, this is a layer of electrical equipment, this building is a total of three floors, see how many square lines are used, the distance is 200 meters.

It is recommended to enter the main line of the building with a 10 square copper core. 6 square copper core distribution lines are used in the distribution box, and 6 square meters are also used for the main line of air conditioning sockets. The rest of the sockets are 4 squares, and the lighting is squared!

Second, there are 8 rooms on the first floor, a room lamp is about 80w, there are about 8 computers on three floors, there are about 8 TVs, and the water dispenser is about 5 in total.

The socket is 4 square, and the lighting is squared enough!

Generally, household appliances use a voltage of 220V, and the water heater is also 220V, so it is better to use a plug.

How many watts is the water heater, the safe ampacities of the square copper wire through the plastic pipe are 12a, according to the formula: the electrical power is equal to the voltage multiplied by the current p=ui, then 220 12=2640 (watts).

So a square copper wire can carry an electrical appliance of less than 2640 watts.