The difference between the first, second and third class distribution boxes
2019-08-31 15:08:00
1. The first level distribution box is relative to a building or workshop, which is the first level distribution box of cables directly led from the substation or municipal distribution station. It mainly plays the role of distribution and summary.
2. The secondary distribution box is the distribution box connected with the cables from the primary distribution box.
3. The third level distribution box is the distribution box connected with the cables from the second level distribution box.
Note: the three-level power distribution is mainly to ensure that each electrical equipment is available; each electrical equipment can be used independently without mutual influence. And save wire.
The first level distribution box is to introduce three-phase power supply, ground wire and zero wire from the transformer.
Class I power distribution box: the construction power distribution cabinet is used for the construction power of the construction site. It is specially designed for the special situation of the construction site and meets the relevant construction power standards of the construction department. The complete set of products can form a complete three-level protection system for construction power consumption and achieve the purpose of one machine, one gate and one protection, which is very suitable for all kinds of projects meeting the standards. The first level cabinet adopts lower incoming and lower outgoing lines, front door opening, main bus adopts copper bar connection, good contact, with metering system inside, safe and beautiful, rain proof box top is suitable for field work.
The secondary distribution box is from the power line of the primary distribution box to the temporary power supply
It is applicable to the construction power of the construction site. It is specially designed to meet the relevant construction power standards of the construction department due to the special situation of the construction site. The complete set of products can form a complete three-level protection system for construction electricity, and achieve the purpose of one machine, one gate and one protection. The secondary box adopts the design of internal and external doors, the external surface is spray molded, safe and beautiful, and the roof of rain proof box is suitable for field work.
The secondary distribution box shall be placed 1.5m above the ground
Main switch 60A - dz47-63 100A
Lighting switch 16A - dz47-63 16A two-phase leakage switch
Air conditioner 1.5p-20a-dz47-63 20A two-phase leakage switch
Electric water heater 8000w + washing machine - dz47-63 60A two-phase leakage switch (because there is no 40A switch, only 32A switch)
Socket switch 16A - dz47-63 16A
The main electrical appliances are refrigerators, electromagnetic ovens and microwave ovens
The air conditioning switch needs to be replaced and the main switch needs to be replaced.
The main switch does not have leakage. Branch switch with leakage protection is the best. Because the human body through 30 Ma with fatal danger. The operating current of leakage switch is 15-30ma
At present, the distribution lines in the city are generally 4 square meters, a little has used 6 square meters. It's better to replace the 2.5 square.
The third level distribution box is the control cabinet of the electrical equipment itself.
Three level distribution: distribution box is set under the general distribution box, switch box is set under the distribution box, and electrical equipment is set under the switch box to form three-level distribution. "Two level protection" mainly refers to the adoption of leakage protection measures. In addition to the installation of leakage protector in the last level switch box, it is also necessary to install one level leakage protector in the upper level distribution box or the main distribution box, so as to form two-level protection in general. The principle of "one machine, one switch, one leakage, one box and one lock" is that it is strictly forbidden to directly control two or more electrical equipment (including sockets) by the same switch.
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