The dangers in the electronic equipments

If you wish to venture into the internal parts of an electric or electronic appliance, either to attempt its reparation or maintenance, or only for curiosity, you must be very clear about the risks you face, and you should know the cautions that you should take, if you do not wish to go by one very disagreeable experience, or even fatal experience (For your physical integrity and/or of the appliance).

The warnings printed in the lids or in labels adhered to the electric and electronic apparatuses, that they alert about the danger of taking them apart or trying to repair them without having the capacity and necessary knowledge, They are not a mere formalism required in the laws at some countries simply (No in all counties regrettably), They are a real warning of the dangers that those apparatuses enclose.

A great quantity of people die annually all over the world, victims of electric shock trying to repair electric or electronic apparatuses without knowledge and precautions that are required. Regrettably that type of news often they haven’t a bigger coverage in the newspaper, at the most, a short note in the page of events. But, if you achieve a search of news about this topic in internet, you can find hundred of cases.

In addition to the fatal cases by electrocution, thousand that if well they do not have a fatal outcome, happen and they are not depicted by the news, they can leave grave sequelae:
Nervous upsets, muscular contractions, ventricular fibrillation, cardiac or respiratory suspensions, sensorial upsets, burns by electric arc, besides of the blows, injuries and falls caused by muscular contraction or convulsions of electric shock’s product.
And if the victim has the luck of being between the more fortunate that outlive the experience without bigger physical damages, he will certainly preserve a very disagreeable memory for the rest of his life.


The dangers inside of electronic equipments of consumption

We can divide the risks of venturing into the inside of an electronic appliance, in two types. The first and more important, the danger of damages to the person’s physical integrity, and the second one, the danger from damages to the appliance.

The electric Shock

The major risk of electrocution, in the inside of any electric or electronic appliance is present when this is connected to the electric net, but believing than with only unplugging the wall plug’s cable danger disappears, it is a terrible error.
A lot of electronic apparatuses like televisions, monitors, microwave ovens, PC power supplies, amplifiers and other ones, even being out of touch with the electric net, they can maintain big electric loads in the capacitors of their power supplies, that they can produce dangerous electric unloadings if someone enters in touch with them or with other elements connected to them.
The equimpments that use CRT (Cathode-Ray Tubes) or kinescopes, because these run on high voltage (to 30000 volts or more) and to that their construction makes that they be able to store electric load, they are also a grave danger if they are not manipulate correctly.

Enclosure, some electronic little apparatuses that run on batteries, like for example the photographic cameras with flash, they can keep loads of dangerous voltage in their circuits, even though have been withdrawn the cells.


A lot of electronic apparatuses, they produce various types of radiations (x-rays, electromagnetic waves, laser emissions), that they can produce bodily injuries if they are switched on and opened or without the safety measures made suitablity. Such is the case, for example, of CRT’s televisions (overcoat the ones belonging to large-sized screen, projectors and retro-projectors), transmitters of radio, cellular phones and microwave ovens.
This type of radiations can produce cancer and/or burns, with only being close to the radiation source, If the safety norms are failed to keep. Their proximity can also affect other electronic devices, that proves to be highly dangerous, for example: For people with pacemaker.

The emission laser of the readers units of CD, DVD and Blu Ray can cause ocular temporary or permanent damages.

Other dangers

The CRT (Cathode-Ray Tubes) or kinescopes, of televisions and monitors, have their most fragile part (the cannon) in the equipment inside. A light blow there you can destroy it, and in some cases causing an implosion that throws glasses fragments this way and that.

In apparatuses with mechanisms, motors and mechanical parts, if they become active while they are manipulated, they can catch you and hurting you a finger or a hand. Some chasses and parts have cutting edges that can cause sections in your skin.

The Damages to the equipment

who we dedicated to the reparation of electronic apparatuses of consumption, we have found frequently, with equipments that they have been opened, perhaps for curiosity, or in an attempt of reparation or maintenance, for the user or by people that they do not have complete knowledge on cares and procedures of safety required. it to producing many times, a consequence of damages than in some cases, they make unviable the reparation.

A lot of electronic components and circuits (some of them, expensive) are delicate, can get damaged if they are manipulated incorrectly. Such is the case, for example, of the semiconductors (transistors, chips, optical readers, etc.) of technology MOS, CMOS, MOSFET, that they can in some cases, getting damaged for the human body’s static electricity, to touch them with the hand without knowing the precautions that to it should take.

In approximately all the electronic modern equipments, the procedure indicated by the manufacturer in the service manual, for to open and / or to taking apart the equipment should keep on, step by step, without causing damages.

Some apparatuses have occult screws, other ones do not use screws and the plastic pieces have teeth and slots that some with other ones insert. If it tries to get disarmed without obeying the adequate steps, the plastic parts it break.

Screens CRT, LCD and Plasma televisions, monitors and other equipments are delicate parts, and expensive, that they can get damaged easily if you do not have the adequate precautions.

Disconnecting modules or a equipment internal circuits, without follow the order and procedure indicated by the manufacturer, in some cases can damage other circuits, even though the equipment is off and disconnected of the electric net or of its power supply. In many instances, it is necessary to discharge the condensers of the circuits of power supply, including the low-tension condensers to reduce the risk from damages to other electronic components.


The purpose of these notes, it is not being to frightening, but creating conscience. While, these are not all dangers that can exist inside an electronic equipment of consumption, they are at least some of the most important. So many equipments and different technologies and every day there is something new, that other ones that we have not mentioned here will without a doubt exist. I hope that these notes are useful to creating conscience on the risks that be running who attempt repair or looking around inside an appliance, without having the knowledge appropriate about it.

If you wish to venture into an electric or electronic equipment’s internal parts and you do not have experience and necessary knowledge, is better idea to leave it at hands of somebody capacitated, for your health and the one to the equipment. Wanting to save yourself a certain amount of money, trying to repairing it yourself the thing that supposed be a loose little cable can result you more expensive!!

If you are a student or fan to electronics, with the basic knowledges of electronics, electricity and safety at these fields and you are willing to face risks, I leave you some recommendations here:

  • Try to have at yours fingertips the manual on duty of the appliance, you can look for Manuals and Diagrams at the internet sites of electronics technics or related forums (maybe some youtube video) and follow the procedures than there it indicate to disassembly and to accomplish checkups safety.

  • Do not work alone, make it under the supervision of your professor or a technician more capacitated that you meet and can guide you. If this is not possible, make sure that at least another person is present, stay near that can help to you in case of an emergency.

  • When you take measurements of voltage or other checkings in any equipment while this is connected to the electric net, maintain always a hand in your wear pocket. Use rubbers or sports footwear with sole of glue. If is possible, use an insulating in-line transformer or a circuit breaker for differential current.

  • Do not use jewels or other goods that accidentally can make contact with the circuits or snagging at some point.

  • Maintain the working space clear of metallic objects and tools that they can produce accidental contacts.

  • If you needs to make a revision or to disconnect components, to weld, or to withdraw parts or another contact type with the off circuit, discharge before, the source’s condensers or power supplies, with a resistance bettwen 100 to 500 ohms 5W. You can also use Condensers’s electric discharger.

  • Use always the correct tools.

  • Do not work at electronic or electric apparatuses when you are tired or absent-minded, or under the effects of alcohol or medications that produce sleepiness or perceptual decrease, the odds of committing a fatal error increase exponentially.


Besides, take into account:

  • The opening of an appliance or artifact annuls its guarantee.
  • A defective reparation for people without capacitating can originate property damage and staffs.
  • The author of this Web declines any responsibility for the misuse of this information.
  • If you do not have technical capacitation you should not open neither manipulating household appliances.
  • The page is susceptible of containing involuntary errors for part of the author(s).
  • You receive this information for free, act for so much under your strict responsibility.