1 threading conduit and wire laying
1. 1 common quality common problems
1) When the wire is laid, it is not wired according to the design drawings, and the wire color is not configured according to the standard.
2) The wire connection is inferior to the inferior crimp cap or not welded, without the rubber insulation tape. 3) The electric wire tube is not straight into the box, the pipe end of the steel pipe has burrs, it is not smooth and has no protective mouth. The electric piping inside the ceiling is irregular, not fixed, not in place. 4) The length of the metal hose and corrugated plastic pipe is more than the specification, and the junction box is not covered or inferior. 5) Steel pipe dark pipe and pipe threading are usually manifested in the steel pipe bending radius is not satisfactory, the joint method is incorrect, the wire insulation layer is damaged, and the wire connection is unqualified. 6) The protective layer of the dark pipeline is less than 15 mm, and some are exposed. 7) The pipe is not tight and uneven.
1. 2 prevention measures
1) Strictly control the variety, specifications, model and quality of piping and various wire boxes; strictly control the variety, quality and insulation resistance of the wires, and must meet the design requirements and relevant technical standards. Products that do not meet the current national standards may not be used or installed.
2) The insulated wire laid in the pipe shall have a rated voltage not lower than 500 V. The wire shall be laid out strictly according to the design drawings when laying the wire, and shall not be changed privately.
3) The diameter of the wiring pipe, the number of bends, the bending radius and the arrangement of the junction box shall ensure that the pipe can be threaded and changed without damaging the wire insulation. There should be no wrinkles, pockets and cracks in the bend of the pipe. The bend radius of the pipe should not be less than 6 times the outer diameter of the pipe.
4) When cutting the pipe, the cutting should be vertical, not broken, the pipe mouth should be flattened and scraped, so that the pipe mouth is free of burrs and smooth and smooth. If there is a horseshoe mouth, it should be cut again.
5) Due to the different parts of the steel pipe thread connection, the pipe length of the pipe section is also different. The length of the threaded wire used in the junction with the junction box of the junction box shall not be less than 1.5 times the outer diameter of the pipe; the length of the threaded wire when connecting with the pipe and the pipe shall not be less than 1/2 of the length of the pipe joint. 2 buckle 4 buckle, when the wire is connected, the length of the thread at one end of the connecting pipe should not be less than the length of the pipe joint plus 2 buckles and 4 buckles.
6) If the steel pipe guard is missing or falling off due to inadvertent operation, it should be filled in time. If the mouth is not in conformity with the diameter, it should be replaced in time.
7) When steel pipe and steel pipe, steel pipe and box (box) are connected by thread, in order to make the pipeline system grounding (zero) line good and reliable, at both ends of the pipe joint and the connection between the pipe and the box (box), Weld the grounding jumper with the corresponding round steel or flat steel so that the entire pipeline can be reliably connected into a conductive whole to prevent the insulation damage of the conductor and cause the tube to be charged and cause an accident.
8) Pipe threading should be carried out after the plastering, painting and floor works of the building; the water and debris in the wire protection pipe should be removed before threading.
9) There should be no joints and kinks in the inner conductor. This phenomenon is not easy to find during inspection and is caused by insufficient length when threading. Construction workers should change the line and wear it in time, otherwise it will cause trouble. The connector shall be placed in the junction box. It is forbidden to penetrate the conductor whose insulation is damaged and wrapped with insulated wires. The number of threads in the pipe is generally not more than 8. The wires of different voltage levels and different watt-hour meters should not penetrate into the same line pipe.
10) Except for the outer wall of the pipe laid in the concrete, anti-corrosion and brushing should be carried out, and the inner wall of the pipe laid in the concrete should also be treated. If galvanized steel pipe is used, all the damaged parts of the galvanized layer shall be treated with anti-corrosion treatment.
11) The dark piping protection layer is less than 15 mm, and some are exposed. The depth of the slotted tube is insufficient. The tube should be pre-buried or slotted according to the relevant requirements. The position of the pre-embedded tube should be accurate.
12) If the pipe is not tight and not flat, the fixed point should be fixed according to the requirements of the regulations. The fixing point should be firm. When piping, draw the line first, use the powder line bag to stretch the wire at the position where the line is laid, and install the pipe. To ensure that the piping is horizontal and vertical.
2 distribution box installation
2. 1 common quality common problems
1) The installation height does not meet the specifications and the position is unreasonable. 2) The verticality and level of the distribution box exceed the standard. 3) The wires in the box are not wired according to the design drawings. The switch and the leaking body in the box will arrange the furniture and the above-mentioned household appliances, so that the installation of the line is simple, and the secondary construction phenomenon of the electrical engineering in the decoration construction can be avoided, and the user satisfaction effect can be achieved. This is the purpose of electrical design.
The electrical protector is not configured as designed. 4) The grounding wire (PE) and the neutral wire (N) are not standardized, and the multiple wires are pressed together, and the weak contact is not good. 5) The N-line and PE line terminals (bus bar) of the distribution box are crowded and inconvenient to operate. 6) The electrical distribution box of the distribution box is cut by holes, no special tools are used for opening, there is no signboard in the circuit inside the box, and the box is not connected with the PE line. 7) The height of the box is not the same from the ground, and the door opening is not flexible. 8) The surface of the distribution box is damaged or peeled off.
2. 2 prevention measures
1) Select the distribution box produced by the regular manufacturer.
2) For the verticality and level of the distribution box, the standard should be strictly checked. Should be found and leveled at the time of installation, so as not to have errors.
3) Seriously study the standard, ground (PE) and neutral (N) are important measures for safety protection, such as ground (PE) and neutral (N), additional busbars, grounding (PE) lines Or the zero line (N) is pressed on the busbar; the multi-strand line should be connected with the terminal block, and the flat pad and the spring pad should be added when crimping, and the bolt should be firmly crimped.
4) The N-line and PE-line terminals of the distribution box should be considered for convenient operation when ordering, and the wiring spacing should be considered to meet the specification requirements.
5) The distribution box should be installed in a place that is dry, dust-free, bright, not easily damaged, vibrated, and easy to check, check and repair. The installation height of the distribution box is generally 1 500 mm from the ground.
6) The inlet pipe (line) hole of the distribution box should be pressed hole. The inlet pipe should be introduced from the appropriate hole and arranged neatly, one hole and one pipe. The length of the inlet pipe should be with the lock nut. 2 buckles 4 buckles with a protective cap. It is strictly forbidden to use gas welding and electric welding to cut holes, and use the hole opener or drill hole to re-circle with a file.
7) The linings should be placed above the pre-buried or reserved holes of the distribution box to avoid deformation of the box.
8) The distribution box selects the product of the live panel and installs it after the plastering is completed. The installation method of the door should be reasonable so that it can be opened 180. It is necessary to strengthen the drawing review, and the distribution box cannot be installed in an unsuitable position.
9) The cabinet must be firmly and reliably connected to the protective zero (ground) line.
10) Separate responsibility when handling.
3 lamps, switches, sockets, fans installed
3. 1 common quality common problems
1) The fixtures are not fixed by T-bolts and fixed with wooden wedges, causing the fixtures to be weak or fall off. 2) The safety buckle of the cord ceiling is taken out of the hanging box and the lamp socket. The hanging box is not in the center of the base, and the cord is not tinned. 3) The hanging chain or the boom type fluorescent lamp is not vertical, the hanging chain is eight-shaped, V-shaped, and the lamp cover is not horizontal. 4) Installed in rows of lamps, the deviation is not straight. 5) The metal casing of the luminaire to be grounded, without protective earthing or zeroing. 6) Lantern buckle bowl can not cover the hole, wooden structure ceiling type combination lantern, fire treatment is not serious, there is a phenomenon of roasting coke roof or cause fire. 7) The appearance of the varnish paint peels off. 8) Switchgear and socket box are inferior products, screwed to the fixed box with standard mechanism nut with wood screws or self-tapping screws, causing the switch and socket to be installed loosely or fall off. 9) The location of the bathroom socket does not meet the specifications. 10) The junction box is buried deep, especially when the wood decoration and soft decoration are buried deep, and there are fire hazards after the switch and socket are installed. 11) The steel pipe is not fixed in the box, and there is no root or cap in the wire connection, which makes the junction box not well grounded.
3. 2 prevention measures
1) It is strictly forbidden to use wooden wedges to fix the lamps. Fixing lamps should be firm and reliable. There should be no less than two bolts for fixing each lamp.
2) The safety buckle of the cord chandelier is taken out of the hanging box. The reasons for this phenomenon are: a.
A plastic cord chandelier was used. The plastic cord has a small diameter and is easy to fall off. A braided wire (purple thread) should be used to secure the safety buckle. b. The hanging box is not in the center of the base. Before the installation, draw the hanging box on the base first, and install it according to the drawing line during installation. c. The cord is not tinned. When intercepting the wire as required, firstly strip the wire at both ends of the wire and tighten the wire to ensure that the lamp is assembled during assembly to avoid leakage.
3) The hanging chain type and the hanging type fluorescent lamp are not vertical, and the hanging chain is eight-shaped, V-shaped, and the lamp cover is not horizontal. The main reason is that the positioning of the pay-off line and the assembly of the luminaire are out of line. When positioning the pay-off line, you should know the spacing of the hoisting chain of the luminaire or the requirements when ordering. For example, first position the pay-off line, when assembling the luminaire, assemble the luminaire according to the requirements of the positioning and release line to ensure the hang of the luminaire The verticality of the chain; the level should adjust the chain, especially the wire should not be stressed, so that the lamp is unbalanced and the chain is unevenly stressed. The boom type fluorescent lamp is not vertical, and the upper part of the iron box can be hooked, and the lock nut is installed so as to be perpendicular to the ground to ensure the flatness of the lamp.
4) Rows of lamps are not straight. The main reason is that there is no pay-off line. In particular, the rows and columns of vertical and horizontal cross-row lamps must be placed with cross-shaped lines. When installing, they should be fixed according to the position of the pay-off line to ensure horizontal and vertical, vertical and horizontal lines.
5) The metal casing of the luminaire to be grounded is not grounded or connected to zero. The main reason is that the lamp has no grounding bolt and the design has no grounding wire. After receiving the drawing, the design of the lamp below 2 400 mm is not grounded. The drawing should be proposed when the drawing is reviewed; the grounding bolt of the lamp entering the field is unqualified. That is, the return refused acceptance, if there are remedial measures, it should be negotiated with the construction unit, the supervision unit (construction unit) and the supplier to sign the negotiation record on the premise of ensuring quality and safety.
6) The lantern buckle can not cover the hole. Mainly if the plastering is not in place or the installation is damaged, the hole is repaired before installation, so that the buckle bowl covers the hole; the wooden ceiling type combination lantern should be fireproofed before installation, and the fireproof coating should be brushed as required. The wood structure is too close to be insulated with non-combustible materials, such as asbestos sheets, asbestos mats, etc., to avoid fire.
7) The paint is peeled off and the appearance is deformed. It is usually caused by transportation, installation or poor storage. The paint shall fall off and be deformed during acceptance, and the supplier shall be responsible for it. The acceptance may be refused. After entering the site, the management of storage and installation shall be strengthened, and the duties shall be clearly defined to ensure the quality of the project.
8) Adopt the switch box and socket box produced by the authentic manufacturer; the installation height of the socket should meet the design requirements, and the height of the socket installed in the same place should be the same.
9) The bathroom should be sealed with a waterproof and splash-proof socket, and the position should be reasonable.
10) The junction box should be embedded in the box. The steel junction box and the box should be welded together by spot welding. The spot welding should be no less than two lengths, not less than 10 mm. The galvanized box should be at the bottom of the box. Add the hole ear and the original box to apply bolt connection, connect at least two places, make the junction box an electrical path, and ensure good grounding. The box should be flush with the wall or board to eliminate fire hazards.
11) The pipe of the steel pipe enters the box and is not fixed. There is no root or cap in the wire connection. The pipe should be inspected before threading. It is found that such conditions should be treated in time. The non-galvanized pipe can be welded, and the galvanized pipe must be connected. Plus root or cap.
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