How to repair electrical wiring damage
Simple wiring faults can be fixed on your own. It must be remembered that all installation work is carried out only with vented wiring, that is, suspended plugs.
To avoid overloading the electrical wiring when using a large number of electrical appliances, make a calculation. For example, the power of all burning lamps and electrical appliances in total is 1000 W, and the voltage in the network is 220 V, then the total current strength will be 4.5 A (1000 W / 220 V). If the fuse installed is 6 A, there will be no overload from the network.
If the lights go out in the house, then first you need to make sure if the same thing happened to the neighbors whose houses are connected to this line. If they have an electric light, then the fault is in your home.
The search for damage is carried out using a test lamp (an electrical outlet with a 15 W bulb and a small wire with a plug attached to it). To test the network, the plug is inserted into an electrical outlet. If the light is on, the network is working.The test lamp is connected to the electrical network under test in series or in parallel with respect to the plug.
However, it happens that only part of the wiring fails, or even some contact. If there is no power in a room, check the junction box from which the wiring goes to that room. If there is no voltage in it, then the damage is before it, if there is voltage, then after it. And so until the damage is established.
All malfunctions must be rectified immediately. Start repairing electrical appliances and networks, the following safety instructions should be remembered. It is prohibited: painting and whitewashing electric wires; hang any objects; pull the plug from the socket for the wire; wipe the burning bulbs with a wet cloth; touch grounded objects (taps, pipes, batteries, stoves, bathtubs, etc.) while working with electrical appliances; with wet hands, touch the switch, the socket, the base of the light bulb, electrical appliances that are under voltage; iron wet laundry with an iron with a damaged wire; install plugs in wet rooms; pour water and cut off the burnt wires with your hands; you must immediately unscrew the plugs, switch off electricity; extinguish the fire with earth, sand, block the access of air to it.
Detecting a malfunction in the cable of the electrical appliance... If the electrical appliance connected to the network does not work, you must check whether there is voltage in the outlet. To do this, a test lamp is included in the outlet. If the lamp lights up, the contact is working. It is necessary to check the cable of the device. The plug of the cable is inserted into an electrical outlet, and at the other end a test lamp is connected to the outlet of the electrical appliance.If the lamp does not light up, the cable is faulty. Most often, the malfunction of the cable occurs at the junction of its ends with a plug or contact pins.
Probes
The probes are divided into two groups. The first set of probes is used to verify the integrity of the compromised network. Each of them consists of two wires, a current source and a current signaling device. The simplest probe is a simple battery with a light bulb. It does not require special probes. Headphones or a radio receiver can act instead of a light bulb. Even a telephone receiver can serve as an indicator of the presence of current in the network. And also an electrical measuring device with a resistor that is set to limit the current flowing through the device. You can use a wattmeter or a voltmeter for these purposes, but in the latter, to increase the sensitivity, the additional resistance is eliminated.
For a probe with a power source from a lighting network with a voltage of 127 V or 220 V, all elements are taken from materials intended for this network: bulb, socket, wire, plug. It is more convenient to install the probe in a box made of non-conductive material. This will eliminate the risk of the lamp bulb exploding while the probe is operating. To reduce the size of the probe, you can use a socket and lamp from a refrigerator or a sewing machine. Cables and probe wires powered by the apartment network are taken from the following brands ShVP-1, ShPS, PVS, ShVVP. Usually these wires are used in irons and electric stoves. You do not need to insert the test leads. The cores can protrude from the insulated wire by 1-2 mm. The insulation of wires from exposed ends of 100-150 mm is covered with rubberized insulating tape in several layers.
The probe with 127 or 220 V power supply can be used in dry rooms, away from grounded household objects and on a dry rubber pad.
To make the tips of the probe, a plastic tube with flanges is ground, a brass or copper rod with a diameter of 3.5 mm is inserted and fixed in each tube. This rod is soldered to the core of the wire. The junction itself is placed inside a plastic tube, the rods from the tube should protrude 180 mm. When working inside the device, the rods should not cause accidental contact, because PVC or rubber pipes are pulled on the rods. The ends of the rod should protrude 1-3 mm from these tubes.
The second group of probes is designed to determine the presence of current in the network. Most of them are indicator screwdrivers. The presence of current in the network using a screwdriver indicator can be recognized by the ignition of a neon gas discharge lamp. The current in this screwdriver flows from the probe to the end where the serviceman places his thumb. There is a 1 mΩ resistor in front of the lamp. At the same time, the human body becomes a conductor. Through it, the current passing through the screwdriver, through the gas discharge control lamp, goes to the ground. Even at a voltage of 380 V, this current will not harm a person, since, as already mentioned, the screwdriver is insured against this by the presence of a resistor. When using the indicator screwdriver, remember that there is also a "ground" wire through which current flows only when the circuit is closed.
You can make a screwdriver indicator from a used pen and fluorescent light starter.For this, the petals are bent, the aluminum glass of the starter is removed, two wires of the neon lamp are disconnected from the contact legs and it is removed. Then a 100-200 kΩ resistor is soldered to one of the ends of the wire. The greater the resistance, the less will be the glow of the lamp, which together with the resistor is inserted into the body of the pen. At this point, a hole is made in the housing opposite the position of the lamp. Instead of a feather, a steel rod of suitable diameter is inserted. In this case, of course, the piston mechanism or pipette is removed from the housing. The free end of the lamp and the metal rod are connected by soldering or threading. The other end of the resistor is connected to the metal cap of the pen body. The indicator thus made records the current with a voltage of 50-220 V AC.
One of the necessary and often used products is a control lamp... However, it must be remembered that it is prohibited to use, but its effectiveness and the absence of other devices speak in favor of its use. At the same time, you must observe safety measures. Most importantly, this device should only be used before the electricity meter. When using the test lamp, wear dielectric gloves and pull them over the sleeves. Household rubber gloves can be used in dry rooms. When working with this device, you must stand on a dielectric carpet, as a last resort it can be replaced with a dry, double-folded household carpet. Place the rug on a dry wooden board. If the apartment has a dry wooden floor or a floor covered with linoleum, then you can do without laying a board.
The lamp must be placed in a dielectric housing with a slot for the light signal.The mesh cover placed over the lamp protects the lamp from shocks, but will not protect you from bulb debris if the lamp explodes. The two wires to the lamp holder must be routed through different holes in the housing. The hard edges of the opening can break the insulation of the wires and this arrangement of the wires will prevent a short circuit. The length of the wire coming out of each hole should not be less than one meter.
When checking the wiring, the test lamp should hang on the wires. If the inspection is performed close to the floor, the lamp should be moved as far away from you as possible. The wire probe holders are made of plastic. The flanges of the probes prevent fingers from falling on the live parts of the installations and on the bare ends of the probes placed in the holders. The test lamp is equipped with an electric lamp with a voltage of 220 V. When checking the network, it is better not to look at the lamp, as it may explode.