Will you inspect whether the operation of the meter box is qualified?

When it comes to "meter box", I believe everyone is familiar with it, but we don't all know how to operate meter box. Although we don't need to operate meter box, it's necessary for us to know more about meter box! How to check whether the operation of the meter box is qualified?

1、 Appearance inspection of meter box shell

The surface of the meter box shell shall be flat, smooth and free of rust, coating falling off and collision damage. The coating used shall meet the requirements of the technical documents. The coating shall be firm, uniform and free of obvious color difference and reflection.

2、 Installation inspection of meter box

a. The layout of all electrical components shall be reasonable and meet the specified requirements;

b. The compartments of incoming line compartment, outgoing line compartment and meter compartment are clear;

c. The model and specification of components shall be consistent with the drawing.

3、 Installation inspection of meter box conductor

a. The current carrying capacity of conductor section shall comply with the standard;

b. When connecting main circuit elements with insulated wires, C. crimping terminal of DT standard shall be adopted, and the phase sequence color code shall meet the regulations;

The wiring shall comply with the provisions of the process documents, be neat, beautiful, firm and reliable;

f. Insulated conductors shall not be laid on conductive parts and shall be protected when passing through metal components;

d. There shall be no joint in the middle of the connecting line between two electrical components;

e. Electrical clearance and creepage distance

The electrical clearance shall be ≮ 5.5mm and the creepage distance shall be ≮ 6.3mm

4、 Insulation resistance measurement of meter box

The insulation resistance of devices with rated voltage of 1kV and below measured by 1000V megger shall not be less than 5 megohm.

5、 Power on operation test of meter box

a. Before the test, the internal wiring of the meter box shall be carefully checked to meet the electrical schematic diagram, and the power on test shall be carried out after confirming that all wiring is correct and the insulation resistance meets the requirements;

b. After the components are powered on, the voltage at the outlet shall be correct;

c. The opening and closing test of electrical components is not stuck or overloaded;

d. For leakage type elements, start the test button and there shall be protection action;

e. Confirm that all outgoing lines and switches correspond to the connection of the meter and can not be confused or misplaced.

6、 Appearance inspection of meter box

a. The product nameplate shall be beautiful and tidy, the steel words shall be clear and correct, and all data shall be consistent with the certificate;

b. The paint layer and coating shall be free of blistering, falling off, pitting, etc;

c. The glass shall be free of scratches and flat, and the aluminum alloy fillets shall be angular;

d. The outlet label and cabinet code shall be correct;

e. The installation schematic identification of concealed case shell is correct and can be installed correctly on site;

f. Lead sealing or metering door lock and other anti-theft measures shall be taken for incoming line warehouse and meter warehouse;

g. The process flow card shall be pasted firmly, and the job number shall be filled in clearly and correctly.

7、 Inspection of grounding and neutral connection of meter box

A. Wu Gong's watch box

The incoming line zero row and incoming line ground row, incoming line zero row and outgoing line zero row, incoming line ground row and outgoing line ground row are connected by 25mm2 (two 4mm2 power lines AC220V are reserved for the electricity meter).

B. Regular meter box

Incoming zero line box and incoming ground wire box, incoming ground wire box and outgoing ground wire box are connected by 25mm2.

C. All meter boxes of Wuhan power supply and Changzhou power supply: except that the wire ends at the meter do not need to be tinned, the other wire ends shall be tinned; There shall be obvious zero and ground marks.

Precautions for operation of meter box:

1 pay attention to safety during power on operation to prevent electric shock accidents.

2 the operator shall make inspection and commissioning records as required, and submit them to the special inspection for delivery test after passing the self inspection.

3. In the process of inspection and commissioning, if it is found that it does not meet the specified requirements, it shall put forward problems in the form of quality information feedback form, analyze the causes, rework, and report to the quality inspection department to prepare factory data after passing the inspection.