Lighting line installation and overhaul

The installation and overhaul methods are as follows:

Installation:

(a) the technical requirements of the lighting line installation

Indoor wiring should not only make the transmission of electricity safe and reliable, but also to make the line layout formal, reasonable, neat and firmly installed.

(2) lighting line installation process

(1) according to the design drawings (actual requirements) to determine the location of lamps, sockets, switches, distribution boxes, etc..

(2) according to the location of the components to determine the path of the wire laying.

(3) Lay wires and connect wires to components.

(4)Check the line

(5)Installation of lamps and lanterns

(6)Energized for trial operation

Overhaul:

I. Fault checking methods

1. Fault investigation

Fault investigations should be carried out before dealing with the fault. To the malfunction present or the operator to understand the situation before and after the failure, asking what signs before the failure, what is the phenomenon of the failure, there is no change in wiring and so on. For example: a part of the lights suddenly went out

, after inquiring about a light on or in a socket when plugging appliances. If you find the fuse burst fuse, you can roughly judge is due to open the lamp or electrical appliances used in the short-circuit fault, and then further investigation. If there is no such thing, but in the absence of anyone to turn on the lights or open other appliances

when the lights suddenly go out, then you can check the fuse, check whether the overload caused by the fuse blown.

2, visual inspection

After the fault investigation, you can further look, listen, smell and other sense organs for visual inspection, that is, carefully observe the line or the external condition of the equipment or operation. Is the first patrol along the line to see whether there are obvious problems on the line, such as: wire broken skin, phase touch, broken line, light

mouth with or without water, burnt, etc., and then key parts of the inspection.

2.1 look at the fuse fuse

(1) fuse break point in the vicinity of the crimp screw, the fracture is small, often can see the fuse screw discoloration, there is an oxide layer. This is due to the screw is not tightened or crimped when the fuse bruised. In this regard, the screws should be cleaned, shims to reload the fuse.

(2) fuse exposed part of the whole burned, only the screw crimping part of a stock. This is due to the short-circuit current, in a short period of time to produce a lot of heat and make the fuse by bursting. Before the failure point is not found, do not blindly increase the fuse, in order to prevent the expansion of the accident.

(3) There is a small break in the fuse. This is due to the current through the fuse for a long time more than its rated current. As the heat at both ends of the fuse can be dissipated through the crimp screws, the heat in the middle part builds up faster, resulting in being melted. Therefore, it can be concluded

that the circuit is overloaded or the fuse is selected too thin. In this regard, should identify the cause of overload and choose the appropriate fuse to reload.

2.2 Check the gate knife, fuse whether overheating

(1) If the screws on the empty sealing of the fire paint melting, some flow out, which are caused by overheating of the appliance.

(2) If the electrical contacts or contacts connected to the part of the copper surface black oxidation softens, crimp screws welded can not be loosened, etc., is also caused by overheating.

(3) due to the wire and switch fuses and other terminal crimping is not solid or wire surface oxidation poor contact, caused by overheating. Aluminum wire directly connected to the copper terminals, due to long-term "galvanic corrosion", aluminum wire is very easy to be corroded, making the contact resistance becomes large, overheating, and most

later lead to circuit breakage.

3, test check

In addition to visual inspection of the line, electrical equipment, should make full use of the test pen, multimeter, megohmmeter, ammeter, clamp ammeter and test lamps and other instruments and equipment for testing.

4, branching road, section check

The faulty circuit, in line with the principle of first easy to difficult, according to branching road or with the "pair of points" section check to narrow the scope of the fault, and gradually close to the point of failure, the general distribution board circuit and the measurement of electrical appliances and inspection is more convenient, it should be the first check, and then The line of

inspection. The "pair of points method" to check the faulty circuit, that is, when checking the faulty line, in about half of its position to find a check point, with a test lamp, multimeter, etc. for testing. If the test point is normal, it can be concluded that the fault in the test point load side; if the test point is not normal, it can be

concluded that the fault in the test point load side. The next step should be in the middle of the "half" of the problem and then look for a test, and so on.

5, maintenance lines should be noted

In the lighting line maintenance process, we must pay attention to safety, generally do not operate with points. Must be indirectly energized operation, the scope of work within the electrical circuit of the leakage protector must be put into operation. Work should be set up to monitor, the staff should be insulated gloves (or clean

dry wire gloves), must wear long-sleeved clothes, wear insulated shoes, use tools with insulated handles, stand on dry insulating objects to work. When working on energized low-voltage distribution equipment, isolation measures should be taken to prevent causing short circuits and grounding. In special cases of electrified lap

When connecting wires, the switch and its following parts should be connected first, and then connected to the power supply under no load condition. When connecting the wire, should be connected to the zero line first, and then connected to the fire wire. Lap the first head, should be the first two ends together after stranding, it is strictly prohibited to take a wire in one hand.

Second, the common faults of the lighting circuit

Lighting lines may occur mainly short-circuit faults, circuit breakers and leakage of three.

(a) short-circuit failure

Circuit short-circuit failure in the obvious manifestations of: a sharp increase in current, fuse blowing fuse, short-circuit point has obvious burn marks insulation charring, serious wire insulation will be scorched, wire burned, and even cause fire accidents.

1, the reasons for the occurrence of short-circuit failure. (1) unqualified line installation, such as insufficient distance between insulated wires, twisted together; wire and point of use equipment connected to the multi-stranded wire is not wrapped tightly, crimping is not solid, there are burrs or wire joints touch

together. (2) phase line, zero line crimping loose, too close, encountered some external forces to make it touch, such as the screw lamp mouth loose, installing light bulbs inside the center of the lamp mouth metal plate and screw stranded part of the collision. (3) bad weather, such as wind so that the insulation support damage, wire friction each other, resulting in damage to the insulation layer of the wire, short-circuit, rainy days when the waterproofing of electrical equipment is damaged, rainwater into the electrical equipment caused by a short circuit, and so on. (4) electricity do not pay attention to safety

full, private connections, such as mobile or electrical appliances do not use the socket inside or outside the two-core wire touch. (5) line long-term overload, resulting in intense heating of the wire, insulation damage, resulting in a short circuit.

2, short-circuit fault check. Find a short-circuit fault, generally should be branching road, segmentation and key parts of the combination of square root method of flexible use of test lamps or multimeters, with the check. Finding short-circuit faults with the test method is a more convenient method.

Check with the test light method is generally the first fault branch circuit on all the light switches off, off the dial down all electrical plugs, remove the socket fuse, and then use a 60W-100W bulb connected to the branch line total fuse

Both ends, and connected to the circuit, and then close the gate to send power. If the test light normal light, indicating that the fault is in the line, if the test light does not glow or faintly glowing, indicating that the line is fine, and then each lamp, each socket to check

check. Check each lamp and household appliances, each lamp switch can be closed and inserted one by one into the household appliances, each switch or insert a household appliance to observe the test light. Normal phenomenon is that the test light is not bright or red, but

far from normal brightness. If you open a light or access to an appliance, test light, suddenly close to the normal brightness, it indicates that the short-circuit fault within the appliance or its power cord. Check the short-circuit fault with the test light method must pay attention to safety

Whole, to prevent electric shock.

(B) disconnection fault

Fire wire, zero wire may be disconnected. Break fault occurs, the circuit has no voltage, lighting does not light, all electrical appliances can not work. The causes of disconnection faults are generally the following: (1) due to excessive load and make the fuse

blown; (2) switch contacts loose, poor contact; (3) wire breakage and connector slack, serious corrosion outside the joints (especially copper, aluminum wires directly connected); (4) installation of the terminal crimping is not solid, the contact resistance is too large, so that contact with the long-term overheating, resulting in the wire and the terminal. Wire and terminal oxidation deterioration; (5) due to poor construction quality or poor quality wire in the corner of the broken core. If a circuit lights can not work properly, that

The trunk circuit has a broken fault. When using a test pen to test the lamp or switch stakes, if the neon bulb glows, indicating that the zero line is disconnected; if the neon bulb does not glow, it is a short circuit of the firewire. At this time should first check the main power switch and the total fuse,

See if there is poor contact, loose wire drag, fuse blown, etc., if they are intact, then gradually from the front to the back to check to find out the point of disconnection.

If there are only a few lights do not light, that is only a local wire breaks, then only need to find these lights *** with the wire can be. Individual lights do not light, should focus on checking the light bulb, lamp, lamp base switch, etc., if there is no problem

Problems, and then check the circuit connected to the lamp.

(C) leakage

1, the cause of line leakage is: (1) the wire is often subjected to sun, rain, moisture, dust and filth and other effects of aging, the decline in insulation; (2) the joints of the insulation is not properly wrapped, the insulation is damaged; (3) the insulation of the electrical equipment for a long time in the more humid or oily environment of the total use.

2, leakage fault finding, when found to have a leakage, first turn off the small distribution board on the main switch or pull down the total fuse fuse, if this time the meter is still rotating aluminum disc, indicating that the meter is faulty, should be removed to verify, such as the aluminum disc

Not turn, indicating that the meter is intact. Then turn off all household appliances and lights, stop using electricity to see if the meter aluminum disk rotation, if rotating, indicating that the line leakage; if not rotating is an indication of the fault leakage point in

electricity equipment. In addition, turn off the main switch or unplug the fuse of the main fuse, unscrew and other bubbles, unplug all household appliances, use megohmmeter to test the insulation resistance between the wires and the earth and wires and wires. Phase line and

phase line should not be less than 0.38mΩ; phase line and zero line and phase line, zero line and the earth or between the shell of the equipment is not less than 0.22mΩ. The use of electric fans, hairdryers, washing machines and other electrical appliances insulation resistance should be less

than 0.5mΩ. Based on the above several kinds of faults, we can only carry out specific measurements and analysis, in order to accurately find out the point of failure!