Black wires on the power supply connection. Electrical short circuit - what is it, causes and elimination
Attention
Shorting wires is a dangerous procedure that can damage your vehicle. Never try to short-circuit the starting wires in someone else's car and be prepared to document your ownership of the vehicle.
Step 1: Use a screwdriver
Drive a flathead screwdriver into the ignition switch and turn it like a key. You will break the lock cylinder, but this method can be effective for starting the engines of many cars made before the mid-90s. Step 2: Remove the ignition switch cover
If the car does not start, remove the screwdriver from the ignition switch and unscrew the screws on the upper and lower panels of the steering column. Next, use a flathead screwdriver to pry the plastic panels away from the ignition switch cylinder and the wires connected to it. Use caution to minimize damage to the steering column. Step 3: Locate the Power and Ignition Wires
Identify the power and ignition wires. Typically, two red wires control the car's power, while one or two brown wires are connected to the ignition. Refer to your vehicle's owner's manual to determine the exact wire color code. Step 4: Connect the power wires
Wear gloves and cut the two power wires from the ignition switch cylinder using wire cutters. Then strip the ends and connect them by twisting them together to supply power to the lights, radio, and other electrical systems. Step 5: Connect the Ignition Wires
Cut the ignition wires from the cylinder and strip the ends. Be especially careful not to touch the bare ends as they contain high voltage and may shock you. Touch the wires to each other, and when the car starts, separate them again and insulate the ends so as not to receive an electric shock while driving. Hint
If your car only has one ignition wire, touch it to the exposed part of the connected power wires to start the car.
Step 6: Understand Your Security Tools
Understand additional security features. On some vehicles, the steering lock can be opened by inserting a screwdriver between the upper steering column panel and the steering wheel. Hint
Modern cars are equipped with complex wheel locking systems and electronic keys, which are almost impossible to bypass without special tools and in-depth knowledge.
Step 7: Turn off the car
Stop the car by disconnecting the power cables. Now it's time to find a spare set of keys and head to the repair shop without delay. Fact
In 2008, the steady decline in vehicle theft in the United States crossed the five-year threshold.
The system case is an important component of the entire computer. It is in the case that the “production workshop” of the entire computer is located, so to speak. It is in the case that the motherboard is installed, and the RAM, video card, processor and all kinds of wires and cables are already “hung” on it. Moreover, the power supply is located in a separate place inside the case, as well as the hard drive and drive.Modern cases look quite attractive, menacing, aggressive, unusual... The developers have enough imagination, which means that ordinary buyers can choose from a huge assortment. But not only do the current buildings have an attractive appearance, they also have “working” advantages. Such advantages are the USB connectors, as well as microphone and headphone connectors on the front of the case, which in turn means that we don’t need to crawl under the table and get to the back panel of the case every time we need to connect a flash drive. I think everyone will agree that these are, in principle, trifles, but still, it’s more pleasant to just insert a flash drive in front and start working.
But, unfortunately, there are cases when some parts of the computer case fail. We are talking about the notorious POWER button, which is available on absolutely every case. Over the course of long-term use, this button may simply fail, for example, stop pressing or, on the contrary, sink deep into the case, and no matter what the “witch,” you won’t be able to turn on the computer. What to do in such situations? If you don’t really need a computer, then it’s better to call a repairman and wait with peace of mind until he repairs everything, paying him a certain amount of money for it.
If you need to use the computer quite urgently, then perhaps you should use the following advice.
First, you need to find a flat surface and carefully place the system unit so that the left cover is facing you, while you should not disconnect all the wires in order to complete everything faster, but you should make sure that these wires are not strained. In addition, a prerequisite must be that the computer is disconnected from the power supply, as they say, you never know. Next, what needs to be done is to remove the left housing cover. In modern cases, this usually does not require any great effort, so this should not be a problem.
After removing the cover, a stunning picture will appear in front of you. You will see everything that at one time you paid a round sum for, and that usually works peacefully, making an innocent noise, and that which now does not want to “start up”. Our attention should be primarily focused on the multi-colored wires that run from the front of the case to the motherboard. There can be a lot of such wiring, and it’s not surprising, because there are also connected POWER buttons And RESET button, and USB ports, along with audio outputs. So, at the next step, we may need a little knowledge of English, which many received at school, because on the wiring themselves, as well as on the motherboard, near the connection of these wiring, it should be written what they mean. For example, you can take USB ports. On the motherboard itself, near the connection, there should be an inscription USB1, USB2, etc. This means that the wires connected to these connectors are nothing more than USB connection ports.
But we shouldn’t forget about our problem, and this means that we need to look for POWER postings(usually these are two wires woven together). Typically, the connectors to which the power or reset buttons are connected are located on the lower right side of the motherboard:
On most motherboards, these connectors are the same and consist of 9 pins arranged in two rows. The last two pins in a short row of 4 plugs are responsible for turning the computer on/off.
Here are the connector diagrams for the most popular motherboard manufacturers.
MSI
AsRock
Asus
Biostar
Epox
Foxconn
Gigabyte
Intel
Once these two wires have been found, you should find where they are connected to the motherboard. Once the connection location has been discovered, it is worth carefully disconnecting these wires so that the small plugs are exposed.
That's it, now we're almost done. The final step is to turn on the computer; for this we need an ordinary stationery pen, preferably one that writes boldly. Once you have found such a pen, you can connect your computer to the power supply, and then carefully run the tip of the rod over these exposed needles. Or in other words, you just need to close these contacts. After these steps, the computer should come to life and the download will begin. If nothing happens, then you should repeat the procedure, but close these needles quickly enough.
Thanks to these simple steps, you can start the computer without any problems, but this should not be neglected, and it is better to quickly repair the start button on the case to avoid unnecessary problems.
Attention: Neither the author of this article nor the administration of this site bears any responsibility for possible problems that may arise when turning on the computer in this way. You will perform all of the above actions at your own peril and risk, and will be solely responsible for possible problems that are not described in this article.
The skill of starting a power supply without a computer and motherboard can be useful not only to system administrators, but also to ordinary users. When problems arise with your PC, it is important to check the functionality of its individual parts. Any person can cope with this task. How to turn on the power supply?
How to turn on the power supply without a computer (without a motherboard)
Previously, there were power supplies (abbreviated as PSU) of the AT standard, which were launched directly. With modern ATX devices, such a trick will not work. To do this, you will need a small wire or a regular paper clip to close the contacts on the plug.
On the left is a 24-pin plug, on the right is an older 20-pin plug
Modern computers use the ATX standard. There are two types of connectors for it. The first, older one, has 20 contacts on the plug, the second - 24. To start the power supply, you need to know which contacts to close. Most often this is the green PS_ON pin and the black ground pin.
Pay attention! In some “Chinese” versions of the power supply, the wire colors are mixed up, so it is better to familiarize yourself with the contact diagram (pinout) before starting work.
Step by step instructions
So, when you have become familiar with the wiring diagram, you can start starting.
Carefully remove the power supply from the system unit
Connect something to the power supply to create a load, for example, a hard drive
Carefully compare the pin layout on your plug and on the diagram
Make a jumper
Many computer enthusiasts have a question: “How to turn on the power supply without a computer?” This need is caused by various reasons, most often we are talking about checking the performance of cathode lamps or new coolers.
Why such difficulties?
It is simply necessary to turn on the power supply without the computer in case of repair, because if you constantly turn the computer off and on, this will negatively affect the PC components due to premature failure of the batteries. In addition, any experiments with the computer may result in unstable operation of the operating system.
First launch
As computer wisdom says, if you can find a PC power supply, how to turn it on is even easier to understand. All modern computer units comply with ATX (a special international standard). Thus, the 20-pin connector has a contact that is responsible for the active state of any such unit. We are talking about the fourth contact from the left (you need to count from the fastening latch). Most often, the contact we need is green. You should try to connect this wire to ground (i.e. any black wire). It is most convenient to use the adjacent, 3rd contact. If everything is done correctly, the power supply will instantly come to life and the cooler will make noise.
How to turn on the power supply without a computer: details
ATX standard devices can output the following voltages: 3.3, 12 and 5 V. In addition, they have good power (from 250 to 350 W). But here’s the question: “How to turn on a computer power supply?” Above, we have already, so to speak, outlined the procedure in a nutshell, and now let’s try to understand it in more detail.
It was easier in the old days
Interestingly, older units that are AT standard could be run directly. With the ATX standard, everything is much more complicated. However, the solution to a huge problem comes down to a small wire that needs to be connected in a certain way. We have already described how to turn on the power supply without a computer, but we ask you to disconnect all the wires going to the motherboard, hard drives, drives and other components. Better yet, remove the element we need from the system unit and work away from it.
Another important point that should not be overlooked: do not let the power supply run idle. This way you can shorten his life. You definitely need to give it a workout. For this purpose, you can connect an old hard drive or fan. As already noted, you will need black and green contacts to start. However, remember that some manufacturers, for unknown reasons, refuse to follow the established color coding. In this case, it is advisable to first carefully study the pinout. If your knowledge allows, you can make a special button to turn on the power supply.
Strange computer power problems: PC stops turning on
First, let's check the presence of a primary power supply of ~220V at the input of the power supply. Among the reasons for the absence are a malfunction of the surge protector, socket, plug, or cable break. The problem may also lie at the source. On the back of many units there is a power switch - this may also be faulty or turned off.
In the case of primary power supply, even if the computer is turned off, there is a voltage of +5V at the power supply output (if everything is working properly). This can be checked by testing the contacts of the power supply connector with a tester. We are interested in pin 9, which has a purple wire (+5VSB).
Often the motherboard has an LED indicating standby voltage. If it is active, both standby and primary nutrition are present.
If the computer still does not turn on, we look for other sources of the problem. We will look at the most common reasons below.
1. Open circuit in the power button. To check this, use tweezers to close the contacts responsible for turning on the power supply on your motherboard, or start the power supply outside the system unit (we described in detail above how to turn on the power supply without a computer).
2. Short circuit that occurs at the output of the power supply. Try disconnecting all devices from power and temporarily removing all adapters from their slots. In addition, you should disconnect all USB devices. You can also deactivate the 4-8-pin power connector for the processor Power Connector +12V.
3. Malfunction of the motherboard or power supply. If only the motherboard is connected to the power supply, but it does not turn on, it is likely that the unit itself is faulty. As for the malfunction of the motherboard, which makes it impossible to turn on the computer's power supply, we note that this is theoretically possible, but in practice it is extremely rare. To check this, turn on without connecting the connector to your motherboard. If the power supply turns on, it is the motherboard that is faulty.
Regardless of the cause, a short circuit in the electrical wiring is one of the most unpleasant (in terms of diagnosis and repair) malfunctions of any electrical circuit - in an apartment, private house or industrial premises. A particularly difficult case is the short circuit of hidden electrical wiring, because the wires are hidden under a layer of plaster. Even if the home electrician’s tools include devices that will help you find the location of the damage without opening the walls, you will still need to remove the wires to repair it.
Types of wiring short circuits, their causes and search methods
It would seem that the reasons for a short circuit in power wiring and their varieties are different issues, but in fact they are closely intertwined. In fact, a short circuit is a consequence of a number of reasons why the phase wire is in direct contact with the neutral wire, or the insulation between them does not prevent the occurrence of an arc discharge (of course, if there is voltage on the conductors). The main reasons why the wiring shorts and what the consequences may be, by which you can determine the location of the breakdown, are as follows:
Physical wear and tear of insulation
Occurs over time and due to even minor but regular temperature changes.
Usually, in this case, the insulation gradually becomes brittle from flexible - cracks appear on it, in which moisture or dust can accumulate. In the event of an unfavorable combination of circumstances, this can provoke the occurrence of a short circuit through a microarc, and this is the most difficult case from the point of view of troubleshooting.
At the same time, outwardly all the wiring looks intact, but when voltage is applied to it, over time it knocks out the circuit breaker.
The search for the vast majority of faults in an electrical circuit occurs on the principle of checking “weak links” - these are any contacts, transitions - all those places where the outer insulation of the cable is exposed during installation. Therefore, in hidden wiring, troubleshooting should always begin in sockets, boxes and panels.
As a result - in this case, a careful inspection of the wiring is carried out - if the circuit breaker is already knocked out, then perhaps the place where the insulation is damaged will be burnt and it will become visible. In some cases, it is necessary to “stress test” the wiring by applying increased voltage to it. This is a rather extreme method, because in essence you have to provoke a full short circuit in the electrical wiring, after which the location of the fault is visible to the naked eye.
For hidden wiring and finding microcracks in the insulation, you can also use a megohmmeter, but it will only show the presence of a short circuit in a localized section of the electrical circuit, and will not be able to determine the location of its occurrence.
After we find the fault, then, depending on the general condition of the wiring, we must decide whether to change the cable or make do with restoring the insulation using electrical tape.
An example of the operation of a megohmmeter is in the video:
Damage to insulation by rodents
This is a fairly common occurrence in rural areas, and in industrial conditions such breakdowns are far from uncommon - mice gnaw through the outer insulation of cables, then the inner insulation and short-circuit the phase with zero.
The difficulty in finding such a malfunction may lie in the fact that it is unknown where the mouse could have chosen a place for its “meal”. But on the other hand, usually the location of the damage is clearly visible, so a superficial inspection of the wire, albeit along its entire length, is sufficient.
It should be taken into account that a complete short circuit does not always occur here - sometimes the mouse can partially damage the insulation and short the wires not directly, but through itself. In this case, there is a high probability of finding the location of the wire damage by looking at the dead animal, which is chained to the chewed wire by a spasm from the electric current. Although sometimes it happens that the mouse is thrown away from the cable, especially if it manages to short-circuit the wires directly and a complete short circuit occurs in the chewed wiring.
Significant overheating of cable insulation
This is not always noticeable to the eye, but when voltage is applied to the wires, an electromagnetic field begins to act on them, which tends to straighten their metal part. As long as the wire is operating normally, this does not matter much, but if too powerful a consumer is connected to it, the wires will begin to heat up. When, as a result, the insulation becomes soft, the conductors, under the influence of the electromagnetic field, will loosen the plastic from the inside, and over time, they will completely break through it. As a result, a complete short circuit will occur and the circuit breaker will be knocked out, and if you are completely unlucky, the cable insulation itself will catch fire.
Until the wire insulation melts, it is impossible to visually notice that it is becoming soft - therefore, after laying a new line or connecting additional electrical equipment to it, it is necessary to check whether the cable is heating up.
Wire manufacturers usually indicate on the labels how much short-term heating the insulation can withstand, but in any case, if overheating has already occurred, then it is better to change the cable.
Direct connection of phase and neutral wires
The reasons why the power wiring is directly shorted can be very diverse - from simple carelessness, which is sometimes allowed during installation, to an accident due to a storm or other natural disaster.
The main thing here is that with direct contact between phase and zero, there is always an abrupt increase in current strength and temperature on the current-carrying conductors. In most cases, the wires are not designed to withstand short-circuit currents, so a mini-explosion occurs at the point of contact, as a result of which the insulation burns out, and flying molten particles of current-carrying conductors carry its ashes around. In this case, there is no particular problem in how to find a short circuit in the wiring - everything is visible to the naked eye - the wires are melted and everything around is covered in soot.
Here it is especially necessary to take into account that soot, which covers the entire adjacent surface, like dust, in certain concentrations is capable of conducting electric current, therefore, when eliminating the consequences of a short circuit, it must be thoroughly cleaned.
How to prevent a short circuit
The easiest way is to follow the recommendations specified in the PUE - almost all entries in this book are preceded by some kind of accident or at least an emergency situation. Well, since most likely no one will learn the rules, you should at least be guided by common sense, which dictates the following:
- If the wiring is old, then replacing it is highly recommended. If for some reason this is not possible, then at a minimum, you need to inspect the contacts of the sockets and assess whether they require additional insulation.
- If the apartment is flooded by neighbors from above, then, even if nothing is short-circuited, this is a reason to reconsider the twisting of the wires in the distribution boxes - under the influence of moisture, the sticky side of the electrical tape loses its properties.
- You need to be careful when driving nails into walls - an unsuccessfully driven nail brings with it a lot of headaches in replacing the broken wire.
You can also simply take a photo of the wires before they are hidden in the wall.
- In the private sector, it is imperative to take additional measures to protect wiring from rats and mice - there are a fairly large number of ways to combat rodents found by home electricians - these can be metal corrugations, coating cables with mastic and other methods.
- If you had to plug a powerful device into the outlet, then it’s worth double-checking whether the contacts and the condition of the insulation are burnt.
An example of searching for a short circuit with a special device is in the video:
Elimination of short circuit consequences
Most often, it all comes down to replacing the damaged section of the wiring, and it is almost guaranteed that you will need to extend the cable instead of its burnt-out piece. The basic rules are as follows:
- The space adjacent to the place where the short circuit occurs must be thoroughly cleaned of soot - it can provoke a recurrence of the short circuit.
- You should not skimp on the wire and try to leave the current-carrying core on which the insulation has burned - it is always better to completely replace the wire.
- If a full circuit has not yet occurred, but the sockets have begun to melt, then you should not try to repair them - after numerous heating/cooling, the structure of the metal changes and the device becomes more vulnerable.
If the wiring begins to short out “from old age” (the insulation has become brittle), then this is an urgent signal for a full repair - in any case, it will cost less than eliminating the consequences of a possible fire.
As a result, should we be afraid of a short circuit?
Usually the process of creating a full short circuit in the electrical wiring takes place very quickly - everything happens within a fraction of a second, after which the protection is triggered. Old-school electricians even have a dark humor on this topic: “Turn it on - if it has a short, we will see it right away.” This means that all necessary safety measures must be applied before an emergency situation occurs, and if it does occur, then all that remains is to eliminate the consequences.