How to choose the current of indoor electricity leakage circuit breaker?

The current of the indoor electricity leakage circuit breaker is selected according to the power of all electrical appliances and the wire diameter of the power supply line. Nowadays, the home incoming line is usually 4 square millimeters. The rated working current of the switch can be 32A. The leakage current is usually 30mA.

For home use, you choose 2p 20a 30ma leakage on it, this is used as the main switch, and the following is connected separately to the 10A sub-switch, and the switch larger than 32A is useless to install at home, and the wire will not jump if it is short-circuited

Depending on which branch it is used on, such as air conditioning, lighting, etc., the leakage circuit breaker current is selected according to the load, which is less than or equal to the maximum overload current of the load.

i = p u, where i - current, p - the total power of electrical equipment, u - line voltage, generally 220v at home;

Once the current value i has been calculated, the rule of thumb is to multiply the calculated current value and then select the circuit breaker.

For example, if the total power of your household electrical equipment is 1000W, then the current of all the devices when they are turned on is:

i=1000 220 and then i*. Then you can choose a 6A or 10A leakage circuit breaker, and you must pay attention to the home use, you should choose a leakage current of 30mA, instantaneous leakage circuit breaker.

In addition, it is recommended to choose electromagnetic leakage circuit breaker for leakage circuit breaker, which has stronger anti-interference ability than electronic leakage circuit breaker.

How to adjust the current value of the leakage circuit breaker? Hello dear, no matter the size of the leakage circuit breaker, it is set according to the size of the leakage current. The small circuit breaker is generally not adjustable, it is directly set, and the leakage value of 250A can not be adjusted, and the brand and model are different, and the ruler may not be able to be adjusted.

If the round wheel or adjustable, such as 380 volt 250A circuit breaker is adjustable, there will be several values on the surface of the circuit breaker, such as 10mA, 30mA, 100mA three values, if the sensitivity is too high, the value is adjusted from small to large. Special attention should be paid to whether the safety protection of people is in place according to the use environment and the use of equipment; Check the lower end of the circuit breaker to be in a safe and good state, which does not affect the safety of human protection, and then adjust the leakage protection value.

1. What is the wide crack of electrical safety leakage current?

1. The safe leakage current of electrical appliances is 30mA. Leakage current is actually the current flowing through the insulating part of an electrical circuit or equipment without fault and without the action of applied voltage. Therefore, Paipong is one of the important indicators to measure the insulation of electrical appliances and the main indicator of product safety performance.

Limiting the leakage current to a very small value plays an important role in improving the safety performance of the product.

2. Legal basis: Article 119 of the Criminal Law of the People's Republic of China.

Crime of sabotage of means of transportation] [Crime of sabotage of transportation facilities] [Crime of sabotage of electrical equipment] [Crime of sabotage of inflammable and explosive equipment] Whoever destroys means of transportation, transportation facilities, electrical equipment, gas equipment, or flammable or explosive equipment, causing serious consequences, shall be sentenced to fixed-term imprisonment of not less than 10 years, life imprisonment, or death.

Crime of negligently damaging means of transportation] [Crime of negligently damaging and prudently closing transportation facilities] [Crime of negligently damaging electrical equipment] [Crime of negligently damaging flammable and explosive equipment] Whoever negligently commits the crime in the preceding paragraph shall be sentenced to fixed-term imprisonment of not less than three years but not more than seven years; where the circumstances are more minor, a sentence of up to three years imprisonment or short-term detention is to be given.

2. What are the precautions for leakage current measurement?

1. The leakage current measurement is live, and the shell of the electrical unit under test is live. Therefore, the tester must pay attention to safety, and all kinds of laboratories should formulate safety operation procedures, and should not touch the tested electrical appliance before cutting off the current;

2. When measuring the leakage current at working temperature, if the DUT is not supplied through an isolation transformer, the DUT should be insulated with a material insulation pad with reliable insulation performance and the ground. Otherwise, part of the leakage current will flow directly through the ground without passing through the instrument, which will affect the accuracy of the test data;

3. The influence of the environment on the test data should be minimized, the temperature, humidity and pollution of the insulating surface of the test environment have a great impact on the leakage current, the temperature is high, the humidity is large, the insulating surface is seriously polluted, and the leakage current value is larger.

With power, voltage is equal to current. For example, if the total power of electrical appliances is 4kw, then 4000 220 = 18a.

It is required that the rated current of the air switch should be greater than the current of the load and load.

In general, the choice of air switch is calculated as a multiple of the load current, 18A*. There is no air switch for 27a, so.

The air switch should be selected as 32a.

Three-phase electricity is calculated as follows.

Power = Current * Voltage * Root No. 3 * Power Factor.

Current = Power Voltage Root No. 3 Power Factor.

For example, if the load is 6kw, the current = 6000 380.

The selection of a circuit breaker requires that the circuit breaker be rated at a higher current than the load current.

Circuit breakers and leakage circuit breakers are both electrical protection devices. However, they do not have the same concept of safe current.

The safety current of the circuit breaker usually refers to the multiple of the fixed current of the forehead rock, and even if there is a large load current in a short time, the protection circuit will be tripped; In addition, there are functions such as overload protection and short-circuit protection.

The safety current of the leakage circuit breaker refers to the action value of the leakage current, that is, when the leakage current of the circuit exceeds the safe current, the leakage protector will cut off the circuit. The main function of the leakage circuit breaker is to protect personal safety and avoid the occurrence of electric shock accidents.

Therefore, the concept of safe current for circuit breakers and leakage circuit breakers is different, and their functions are not exactly the same. When using electrical equipment, the appropriate electrical protection device should be selected according to the actual situation to ensure the safety of electricity.

The advent of the electric age has brought great changes to our lives, and it has also brought certain dangers. With the increase of household electric hand dismantlers, the voltage withstand value is limited, and it is easy to have leakage problems, so many people will install leakage circuit breakers to ensure the safety of electricity. So what is a residual current circuit breaker?

The leakage circuit breaker is actually a protective device that acts as a switch when the leakage current is greater than the rated value in the circuit. The leakage circuit breakers on the market can be divided into two types of products according to their functions: voltage and current, among which the current leakage circuit breakers can be refined into two categories: electromagnetic and electronic. The biggest function of the leakage circuit breaker is to prevent excessive current, causing leakage problems, and reducing the occurrence of potential safety hazards.

When the user is electrocuted, the neutral line in the circuit will produce high-voltage current to the ground, causing the leakage circuit breaker to run, so that the circuit switch jumps. The current leakage circuit breaker is mostly used in the low-voltage electricity grounded by the transformer, and when the user is electrocuted, the leakage is detected through the internal induction system, so that the leakage circuit breaker operates, resulting in the power supply being cut off.

1.Due to the serious consequences of direct electric shock and the greater harm, it is recommended to choose a product with better flexibility in the selection of leakage circuit breaker. This kind of leakage circuit breaker should be installed on the circuit of the circuit, it is best to choose a product with a current of 30mA, the working time should be kept in, it is used more in many residential spaces, and it is recommended to install it at the location of the main meter at the entrance to the house.

2.If there is a problem of contact with electricity in different places, the damage to the human body is not the same, so it is necessary to select the corresponding leakage circuit breaker products according to the actual situation of the place. Compared with dry space, wet space is more prone to electric shock problems, so it is necessary to choose a leakage circuit breaker with a current of 15-30mA and a working time.

3.If it is an electrical product used in water, the current value between 6-10mA should be selected for the leakage protector, and the working time should be within the us, and the other person should stand on the metal electrical appliance. Once the current exceeds 24V, a leakage circuit breaker with a current below 15mA and a holding time within US should be selected.