Electricity troubleshooting

see also physics, electricity, understanding of electrical current"

Breaker/fuses, plugs, cords.

1/ The general circuit-breaker blows and it can no longer be reset, it is reset again. Remove all fuses and switch off the circuit breakers partial of the electrical panel (near the meter). If this frightens you, or if the painting is doubtful, wear gloves, preferably latex, insulate your feet from the tiles. (plastic or rubber soles, no leather or wet fabric). Reset the general circuit-breaker by lifting a small lever or pressing a button (green). Replace all fuses or partial circuit breakers one after the other until the main circuit breaker blows. Eliminating the faulty one allows you to have power elsewhere. In the area covered by the incriminated fuse or partial circuit breaker, disconnect all appliances and start again as at the beginning; put the fuse or partial circuit breaker back on; since you have disconnected everything from the offending section, it will not blow if it is a defective device. Now connect all disconnected devices one after the other. You must find the defective device, plug, or extension cord. I isolated the electric stove from a neighbour whose the main circuit breaker had blown, depriving her of all power in the house.

2/ The general circuit-breaker blowss and it can be reset. The fuses and partial circuit breakers in the panel must be checked. For a circuit-breaker, it is necessary to see if it jumps again or not: lift the bar or press the button (green). For a fuse, it is more difficult: depending on the case, pull or tilt a fuse holder towards you by hanging it from above; if the end of the fuse has a small red dot that protrudes, replace the (10, 15, 20 Amperes... it says so on it). There is no red dot. Replace the one that serves an appliance that no longer works or a light that no longer lights up. If not, all of them must be replaced one after the other, or test them (see below, "my tester". If your circuit breakers and fuses are not marked (assigned to sockets, machines, lamps, heating etc.), take advantage of this opportunity to do so. The correct fuse is replaced but it blows again. It is the plug, the device, the lamp, the cord that is involved.

3/ Checking the wall socket. To check the presence of power, connect a mobile lamp (bedside...) to the wall socket or use one of these small screwdrivers on the yellow transparent handle that have a small neon bulb inside (the handle lights up when you put the screwdriver in one of the two "holes" of the plug, which is called the main, but not on the other.
If nothing lights up, check that the plug does not have its own fuse (rare, but...) There must be a small round cap (serrated or with a slot for a screwdriver or coin). Unscrew and examine. the fuse under the glass tube). Replace the fuse. A wall outlet has decorative covers that must be removed up by inserting a blade. Two screws are then found halfway up the grip, on the left and right respectively. TURN OFF THE POWER. Unscrew the two screws, the plug moves and simply pull it towards you. There are two or three electrical wires, one of which is a yellow and green "ground" wire, plus there is another connection on it. If no wires are broken, check the tightness of the screws that hold them (without excessive force, but firmly).

Wall socket, plug. The danger sometimes comes from the wall sockets and the plug of the device. The contact may be defective between the plug and the socket, or the loose wire inside the socket. To make sure everything is correct, touch the plug and socket and if they are hot, there is an anomaly on either one. Try again with the device connected but off to deduce the right conclusion.

It is the cord of a device that is involved. It must be checked (see below for a cord of an iron, or extension cord).

A device no longer works It may have a fuse. Examine your device. It can be accessed from the outside (under a screw door) or under a round cap; if not, open the unit and look inside if you do not see a fuse under a glass tube (can be hidden under a screwed trapdoor). I have thus restarted an old HI-FI chain, connected to my PC (microcomputer) and a microwave oven. The difficulty is sometimes to open the device because screws are becoming rarer and rarer and it is often "clipped" : For this, see "Dismantle, reconstitute..."". Note: If the new fuse blows, try once with a "stronger", example 3 amperes instead of one, but do not insist further, as it is probably more serious.

Continuity tester. It is a small assembly that will be useful to you. To CHECK AN APPLIANCE CORD, EXTENSION, FUSE, MULTIPRISE, Battery or battery.

>Base: a 4.5 volt flat battery lamp (or 3 round batteries in LED model) is used. A 6 to 8 mm wide strip is cut from a credit card (keep expired cards). See PHOTO. We see the two electric wires, to be prepared as follows: take 30 to 40 cm of electric wire flexible, and separate the two conductors by a few centimetres. Strip them on a good cm and stick each end on one side of the plate, crushing them, so that the two conductors are separated by the thickness of the insert (they face each other). Cyanolite glue is recommended, as it will be necessary to scrape the copper strands to remove the glue (it must shine). Insert this board into an open flat electric lamp, at the switch between the blade pushed by the switch and the stud on which it makes contact. It may be necessary to move the stud away from the stud to slide our assembly into it. The button can then be pressed to pin it down. By contacting the two bare wires at the other end of the wire, the lamp should now light up. Last point, of course, it is necessary to close the case as well as possible or put an elastic band, without hurting the wires, so that contacts with the bulb can be made.

NEVER put into the wall socket!!! or try on a device connected to the mains. attention !, turn off the power at the meter (put on plastic gloves, insulate yourself from the ground, even if dry). There are measuring devices on the market (multimeters). Count 25 euros 2016, but you have to learn how to use it. In particular, they can be used to measure the voltage of the batteries or the mains supply, or the value of the resistances. Our assembly cannot operate with a high resistance, for example that of a filament light bulb; a thin winding etc. But it can gain in sensitivity if one is mounted with a higher voltage battery (Lithium 6 volts or more) and a suitable bulb, or LED, slightly overloaded in direct short-circuit.

Exercise with an extension cord and an iron cord.
Check the tester by joining the two wires.

Extension cable. Place one of the tester's wires on one of the plugs of the extension plug, then the other in a holes in the female plug: it must light up on one of the two! Make sure that the metal is properly touched in the holes of the female plug. About the extension cord, think about the power of the lamp or device you are connecting to; for a normal lamp (100 watts max), a small wire diameter will be sufficient (0.75 watts) but for a halogen lamp of 500 watts or more, a washing machine, a larger wire diameter will be required (from 1.5 to 2.5 mm).
Iron cord. Unscrew (or unscrew with a thin blade) the back plate of the iron and place one of the tester's wires on one of the male plugs of the cord plug, then the other on one of the two or three screws or the corresponding pins: it must light up on one of them. If not, repeat by stirring the cord near the iron, then near the plug; there may be bad contact or cut wire (it usually cuts there). Do the same with the other plug, it must light up with the other screw.
You now know if the cord needs to be changed (or cut to shorten it) or if it is the iron that is broken.

I made this assembly to check its viability. The lamp that lights up when testing the cord is real! It even amused me! A good habit is to check its operation before and after any test.
It must be understood that the lamp will only light up for one conductor without too much resistance and that it will not be possible to test the continuity of a thin and long winding (iron resistance or something of the kind) Other possible use, of more frequent use, battery voltage tester ! Without a measuring device, the continuity tester can be used on cells and batteries, cell by cell, because you can see the brightness of the bulb, by comparison, those who light well or little. The indication will be good because in flow on a "receiver", the bulb connected.

Yarn continuity tester, other version.

Diagram opposite: we use a flashlight bulb and the socket in which it is screwed (to be recovered in a used lamp or bought if we find it). You also need a compartment for two AA or AAA batteries that are also collected in a toy or disposable or self-made device. Enlarge the diagram to better see the assembly!) The two batteries are traditionally mounted inverted to be "in series". The next step is to solder or fix by winding several turns of stripped wire tightly (strip beforehand). Either the end of an electrical wire on a battery terminal, and the other on the base of the bulb; another wire will be soldered or wound on the outlet of the base. A second thread, here in green, will be connected to the other battery terminal. To test the continuity of an extension cable, its input with test tip 1 and its output with test tip 2 will be touched. The lamp should light up; always check the assembly by bringing together t1 and t2 before each test.

NEVER put into a wall socket !!! nor try on a device connected to the main

A simple neon tester is commonly found, usually sold with a small screwdriver - always useful - whose translucent handle contains the small neon tube. The tester is held in the hand, placing the middle finger on the metal top when there is one, and the tip is placed on the wire or terminal to be tested: if there is current, the neon lamp lights up. This tester allows you to recognize the so-called "phase" wire in a wall socket, which has power and the other one, "neutral", which does not. Practice by putting the tip in the holes of a plug (it's safe, but be careful not to touch the screwdriver shaft, which is normally partially insulated; you'll see that the neon lights up only in one of the holes! this The device can therefore be used to test the presence of power on a wall socket but also at the end of an extension cord, an iron cord, etc. However, this tester is very sensitive and can be turned on on a simple very low current leakage, or a return after passing through other circuits. In this case, it is necessary to check the force of the current that is detected using a lamp, if not a multimeter, mentioned above. Check with a bulb. Prepare a assembly with a flexible electrical wire, a socket for a small refrigerator or sewing machine lamp and its bulb (12/ 15 watts, 230 volts). Strip the end of both conductors and attach each to a rigid wire or stick (adhesive tape). A "crocodile clip" can be screwed or welded to one of the wires or wires two. To check for the presence of electrical current, touch (pinch) the two wires of your assembly on those that are to be checked (lamp, motor...); there may be a third wire called "ground" or "neutral", often green and yellow, connected to the chassis or metal part.
attention !, put on plastic gloves, isolate yourself from the ground, even dry. DO NOT TOUCH THE TWO WIRES TOGETHER. Tip. To be taken with great caution: to test the presence of an electric current at the ends of two wires molded in a connector, therefore inaccessible, prick a safety pin (or finer depending on the cross-section of the wire), in the sheath of each electrical wire, right in the middle, to reach the copper. UNPLUG, CUT THE CURRENT BEFORE PICKING, put on gloves, insulate your feet from the ground on tiles, even if very dry (no leather soles or rope, but rubber or plastic. On 230-volt power, WARNING ! cut off the power during the preparations, check that the tester's wires (pins...) do not touch each other.

First check: contacts, often involved due to low voltage Remote Control: if your remote control no longer works, before replacing the batteries, rotate them in their housing and check that they are tight between the contacts and springs, especially if the remote control has fallen. Choice of batteries: there are no mandatory regulations manufacturers to give the capacity of each battery, too, defy the names "super power", "new", low prices (but not always!) etc; it is better to check yourself by noting the date of purchase, especially if you're a big consumer. I bought "supermarket" batteries that didn't " hold" and that were ultimately very expensive to use, and others that were good.

The truth is that they can be very irregular, as can batteries. That's why I recommend checking them before replacing them, even if only on a flashlight bulb.
February 2017; the "scraper" no longer working, I check his batch of four AA batteries, all identical. Total surprise, two elements are like new, at 1.6 volts! (never seen before), while the other two are at 1.3 and 1.1. With two new batteries, it leaves like never before. Such a gap is exceptional (it seems that the two maids didn't serve!). However, a smaller but significant difference is not so rare.

Voltage (voltage)- To check the voltage of a cell or battery, there are small inexpensive measuring devices, but you can already check by comparison with a bulb screwed on its base, connected to two electrical wires ("my test setup", think about it before throwing a flashlight). One can then roughly compare the respective lighting or simply see that the battery produces practically nothing.

Batteries.
Classical batteries; why discharge a battery before charging it? A battery does not fully recharge because it has "memory" and over time, its capacity is gradually decreasing; therefore, they should be unloaded regularly. This can be done from time to time by leaving the devices running until they stop. Lithium battery: they have a large capacity and do not have a "memory" which means that they should not be discharged before recharging. But they are expensive and do not last for their price. Unfortunately, batteries are rarely included in the warranty.
Conservation of lithium batteries : the manual says: discharge the battery normally and completely with your device until it no longer works; stored then the battery in a cool, dry place.
Replacement of special batteries with commercial batteries. See below. This example applies to all the others if possible (sufficient space): rechargeable drill block, etc.

14.4-volt drill/driver block, or 12 Ni-MH (Nickel-Manganese) battery cells replacing Ni-Mn (Nickel-Manganese). The photo on the right shows the replacement of an element: two black electrical wires - a kind of flexible two-wire electrical cord wire - connect a negative pole (green line) to a positive pole (red cross).
To begin with, I had welded LR3 (AA), but although they had the same energy, 2100 ah, they did not support the effort of the screwdriver. So I renewed with Ni-MH batteries 2100 Ah large model C or HR14, which have a much lower internal loss.

Of course, we can replace several of them, and this is what I have done gradually; DIFFICULT, the new ones are slightly larger and cannot be placed without tinkering with the battery compartment. For example by opening one side (which I ended up doing). Consideration of the price must also be given attention, as the new device may be more interesting. Avoid the most expensive batteries. Without advertising, I had very good results with Clartec (Lecle...), at almost half price, at the time. The difference may be small. To check, everything is constantly changing to deceive the buyer.
Disassembly. The housing opens by removing four screws. Other case, see demount

Detection of defective battery cells. I found that after running the engine while charging (drilling, suction force etc.), two batteries were warm, one hotter and the last one very hot. A measuring device confirmed that two of them had more than one volt, while the other two were very low (0.8 and 0.4 volts). We check here that the best battery is the one that heats the least and the worst the one that heats the most. Without a measuring device, the continuity tester described in the first column can be used, with the elements still good lighting the bulb alone.

It is useful to know how to solder tin to connect wires together, to reinforce the bare end of an electrical wire made of wires, to solder a wire to a thin sheet metal plate or even, in general DIY, weld two thin sheets together to form a particular part. Thin sheet: I think of the metal in cans, ideal for any handyman.
I recommend a 40 watt soldering iron for fine electronics (printed circuits), 60 watts for common electrical soldering, such as electric wires on terminals, between them, or on thin sheet metal (tinplate) such as tin can.

On larger metal frames, it would take 100 to 300 watts, otherwise it would be impossible to tin.

In the case of batteries, it is a matter of soldering one wire on each pole. Do not heat too long (cool as soon as possible with a wet sponge). (see below soldering instructions). The very fast obtaining of the temperature at the chosen point limits the propagation of the temperature to the entire battery body. Protection can also be provided by coating the battery or any other part with a piece of wet thick fabric, leaving only the part to be welded largely unobstructed.

Tin soldering. Learn to tin and solder electrical wires on ELECTRICAL COSSES, or WHITE IRON on WHITE IRON (tin can). It requires a 60 watt iron with a

small fine tip (opposite). The tin used will be packaged in wire about 1 mm in diameter, with pickling core (the pickling agent is in the centre of the yarn), the yarn is packaged in reels.

1/ Drive. Soldering iron very hot, melt a little tin at the end of the purlin, then place the tip of the purlin on the end of the wire by approaching the end of the tin wire from the coil against it. Tin melts in the strands of the wire (if it is too thick, heat and shake the wire to remove excess tin).

2/ Solder on the battery (refer to the 14.4 volt block discussed above); the tin coil, in red, is below the scissors. Gratter a small surface (knife) on the positive pole of a battery (tip) as well as on their negative bottom (flat). If metal strips remain on the original batteries whose wire has been cut, solder on (may not need to be scratched). Firmly place the tip of the tip of the tip on the scratched part of a pole of the battery (inclined tip); melt a little tin on it, at the contact point "tip of the iron-pole more" to heat the surface to be welded faster. Rubbing the tip of the iron on the surface can make it easier for the tin to catch on the metal. TIP. To prevent the battery from overheating (or any other part to be welded), it can be wrapped in a cloth. wet).
As soon as the tin has set on the battery, the tin stain widens as it flattens and its edges finish very thin (does not form a ball); then approach the end of the wire that will drown in the middle of the tin stain. Do not move until the solid state is restored.

Hold without moving until it cools. This is easy to learn, but I advise beginners to practice beforehand with electric wire and tin can iron. a failed (dry) weld that is worthless is matt and forms a cluster that does not extend over the weld wire (if this happens, it is because the metal is not weldable, not clean, or not hot enough (scratch it beforehand, or also if you have moved. There are beautiful welds that are simply placed on the metal, without sticking; in this case, the edges "leak" generally the metal, are thick and form like a ball, instead of being thin at the edges. All you have to do is pull hard on the wire to see if it holds well. A badly soldered wire and simply "glued", doesn't hold.

Delicate work. What can be done on a printed circuit board? Not much, it is true, but again by observing, we can help him in two or three typical cases! What can you see? A poorly soldered wire or element (transistor) (see above), a broken wire (it happens), or the cracked circuit board. That's about it, but believe me, I've already fixed it several times. Soldering on a printed circuit board requires precision and lightness so as not to burn or short-circuit everything. You need a fine point iron, little soldering, and - depending on the condition, it is to be seen, strip the copper plate to be soldered. Not always easy to see: a weld is matt, or shiny but its edges no longer stick to the wire or copper of the plate, the element moves with the finger. You have to weld it together. AND DISSOUDER before so as not to overload - The plate is cracked and one or two copper "wires" are cut, check by slightly bending the plate or observe with a magnifying glass and strong lighting. What to do? Join the two sides of the interrupted "wire" with a strand of copper. A large illuminated magnifying glass is too expensive for very occasional use, but you can make a simpler one on a stand and have good lighting with a 20 watt halogen spotlight.

DESSOLDERING. There are three ways to desolder: by heating and pulling, with braid, or with a desoldering pump. Heat and pull If the weld is heated by pulling on the welded element, the weld is not removed, unless a brush stroke is applied at the same time; the element can then be replaced by heating and adding a little "fresh" weld. Desoldering braid. To remove the weld, place of the braid to be desoldered between solder and wiped iron, which removes the liquid solder by capillary action. Soldering does not require any special skills for wires on terminals, but becomes delicate on printed circuit boards. The operation can take time if the soldering iron is not powerful enough for the size of the solder (or the metallic mass on which it is placed). Desoldering pump. For a printed circuit board, it is essential to use a "solder vacuum cleaner" called "desolder", whose nozzle is placed on the solder heated with an iron, and triggered to suck up the weld. It is a small tube with pump and spring that is compressed beforehand. It sucks the liquid solder through the hole in the nozzle (body to be unscrewed and cleaned regularly).