Do outdoor billboard switching power supplies need to be equipped with leakage protection?

The switching power supply is installed outdoors. It must be placed in a rainproof iron box and a surge protector installed to protect the switching power supply. and cameras, the installation height should be lower than the building.

Make sure the wires have no joints inside the tube.

If it rains and the circuit trips, first determine whether the line is leaking in the 220v power supply part or the 12v part. When tripping, first disconnect the 12v output (disconnect the 3 circuits in groups) , the switching power supply is disconnected from the 220v, and the 220v line is left, you will know where the problem is. There should also be a rainproof equipment box at the connection point between 12v and the camera.

Add a leakage protection in front of the switching power supply, the kind that switches the neutral line and the live wire at the same time.

The key is to look at the usage situation of your motor. If it is used in a situation where people can come into contact with it, a leakage protection must be added. You just need to add a 3P+N false alarm, and the operating current is 30 mA. The 3P+N false alarm can carry a single-phase load, a three-phase load, or a two-phase 380 volt load (the load between two live wires). Added before motor power supply.

Required. A leakage protector must be installed in the switch box, and the installation of the leakage protector should meet the requirements.

Electrical equipment with 36V and below does not need to install leakage protectors if the working environment is dry. The leakage protector should be installed on the load side of the power isolating switch of the distribution box and the load side of the power isolating switch of the switch box.

Construction sites generally follow three-level power distribution, so the electrical boxes should also be arranged according to levels, that is, under the main distribution box, there is a distribution box, and below the distribution box there is a switch box. The following are electrical equipment.

The distribution box is the central link in the power transmission and distribution between the power supply and the electrical equipment in the power distribution system. It is an electrical device specially used to distribute power. All levels of power distribution go through the distribution system. Electrical box.

The main distribution box controls the power distribution of the entire system, and the distribution box controls the power distribution of each branch. The switch box is the end of the power distribution system, followed by the electrical equipment. Each electrical equipment is controlled by its own dedicated switch box, with one machine and one gate.

Do not use one switch box for several pieces of equipment to pre vent misoperation accidents; do not put power and lighting controls together in one switch box to pre vent power line failures from affecting lighting.

The switch box is connected to the power supply and the electrical equipment is connected below. The operation is frequent and dangerous, and must be paid attention to. The selection of each electrical component in the electrical box must be compatible with the circuit and electrical equipment.

The electrical box should be installed vertically and firmly, with operating space around it. There should be no water or debris on the ground. There should be no heat source or vibration nearby. The electrical box should be rain-proof and dust-proof. The distance between the switch box and the controlled fixed equipment should not exceed 3m.

According to "Installation and Operation of Leakage Protectors" 2.1 Equipment and places where leakage protectors (leakage switches) must be installed:

1. Mobile electrical equipment and handheld devices belonging to Class I type power tools (Class I electrical products, i.e., the product's protection against electric shock not only relies on the basic insulation of the equipment, but also includes an additional safety pre caution, such as grounding of the product enclosure);

2. Installation in a humid environment , electrical equipment in harsh places such as highly corrosive environments;

3. Electrical construction machinery and equipment at construction sites;

4. Electrical equipment for temporary use of electricity;

5. Socket circuits in guest rooms of hotels, restaurants and guest houses;

6. Socket circuits in buildings such as government offices, schools, enterprises and residences;

7. Underwater lighting equipment in swimming pools, fountains, and baths;

8. Power supply lines and equipment installed in the water;

9. Electrical medical equipment in hospitals that are in direct contact with the human body;

10. Other places where leakage protectors need to be installed.

Extended information:

The leakage protector has high sensitivity and fast action in response to electric shock and leakage protection. This is the advantage of other protective appliances, such as Fuses, automatic switches, etc. are incomparable.

Automatic switches and fuses must pass load current when normal, and their action protection values ​​must be set to avoid normal load current. Therefore, their main function is to cut off the phase-to-phase short circuit fault of the system (some The automatic switch also has overload protection function).

The leakage protector uses the residual current response and action of the system. During normal operation, the residual current of the system is almost zero, so its action setting value can be set very small (usually mA level). When a person gets an electric shock in the system or the equipment shell is charged, a large residual current appears. The leakage protector will reliably act to cut off the power supply by detecting and processing this residual current.

Reference: Baidu Encyclopedia-Leakage Protector