For the selection of home improvement circuit breakers, please ask about household circuit breakers

If the sub-switch is already equipped with leakage protection, the main switch is not needed.

It is recommended that the leakage switch for sockets and kitchens and bathrooms is generally 30mA leakage current.

The rest of the lighting power is not leakaged.

In this way, the main switch does not need to be leakaged.

The size of the switch is related to the power consumption Since yours is a single phase, so the planned power kW 220V = current switch is a switch that is one level larger than this, such as: you calculate the current 9A corresponding to the switch 10A (the rated current of the switch is generally 10A 16A 20A 25A 32A 40A 50A 63A).

But if you actually choose, it is best to choose 16a (the number of poles of the same manufacturer of domestic micro-break switches is about the same).

Of course, if it is a joint venture brand switch, there is no need to be a big one, in the final analysis, it is still a problem of switch quality.

It's too wasteful for you to use it like this, a switch plus leakage is enough.

You calculate how much power (kw) the whole house uses, and then multiply by 2 to get the switching current you want to choose.

I estimated that you would have to use a maximum of 25kW in total, so a DZ47 60A 2P + leakage would do. Leakage is an ordinary 40mA, which is only for home use.

The main switch does not use a leakage switch, but the bathroom also needs to consider the water heater, the square line is a little small, and the water heater and bath bomb need to use 4 square wires, that is, now do not use the electric water heater to lay the wire.

The total miniature circuit breaker can not use leakage protector 40 2p, each room lighting 16 2p can be, bedroom air conditioner 32a 2p with leakage 4mm2, kitchen socket 25a 2p with leakage 4mm2, (master bedroom, second bedroom, living room socket) 16a 1p + n with leakage.

According to the electrical appliances and wire diameter recommendations, item 10a can be item 16a, the main switch can be equipped with leakage protection, and the rest do not need to be matched, CHINT switch is OK.

How to see these letters on the surface of household circuit breakers? What does it mean? Detailed explanations provide reference.

The maximum short-circuit capacity should be calculated as with the MCCB and MCCB.

The design and use of MCB is for 50 60Hz AC power grid, if used in DC circuit, it should be converted according to the magnetic trip action current provided by the manufacturer and the frequency change coefficient of the power supply; When the ambient temperature is greater than or less than the calibration temperature, the current rating of the MCB must be adjusted according to the temperature and current-carrying capacity correction curves provided by the manufacturer.

The short-circuit current of the low-voltage distribution line is related to the electrical parameters such as the wire cross-section of the power supply line, the wire laying mode, the distance between the short-circuit point and the power supply, the capacity of the distribution transformer, and the impedance percentage of the intelligent low-voltage circuit breaker.

The low-voltage side voltage of the distribution transformer in general industrial and civil buildings is mostly 1600kva and below, and the short-circuit current of the low-voltage side line increases with the increase of distribution capacity. For different capacity distribution transformers, the short-circuit current at the low-voltage feeder end is different. Generally speaking, for civil residences, small shopping malls and public buildings with isolation circuit breakers, due to the low-voltage power supply of local power supply enterprises, the cable or overhead wire section of the power supply line is thin, and the distance between the electrical equipment and the power supply is far, the MCB with the above breaking capacity can be selected.

For users who have a dedicated supply or 10kV substation, often due to the thick cable section of the power supply line and the short power supply distance, the MCB with a rated breaking capacity of 6KA and above should be selected.

Hopefully, you only choose *** household leakage protectors and check them often. Appliances with large loads should have separate circuits. ]

According to the power of all the appliances in the home plus the sum of the power of the appliances that you want to increase in the next few years, calculate the current, and the selected circuit breaker should be about a multiple of the calculated value. Current i = power p divided by (current i multiplied by power factor. For example, if the calculated current is 40A, select 60A.

The brand is not recommended that you choose to be produced by an unknown small factory, and it is also necessary to buy a foreign brand (foreign brands are also made in China). We generally use Chint or Delixi. DZ47-60 C60 is only about 20 yuan, and 2P with leakage protection is more expensive, about 50 yuan (above**non-wholesale**, and it is the Suzhou market)].

1. Generally, like a socket, a device with a conductive (such as iron) shell, in addition to grounding, leakage protection can play a protective role. If you accidentally touch the L pole (live wire), it will be protected, if your left hand touches the L (live wire) and your right hand touches the n pole (zero line), it will not work, you will only be shocked.

2. The size of the miniature circuit breaker is usually according to the mold 9. The miniature leakage circuit breaker is assembled with a small leakage accessory, which is not a mold.

3. The selection of the front and rear circuit breakers should pay attention to selectivity, such as rated current, short-circuit breaking capacity, etc., which should be learned.

I recommend buying a book about it!