Page: 155 of 163
Electrostatic charge flowing from a finger or other conductor can damage
motherboard or other static sensitive devices. Such
damage can shorten the life of the device.
To avoid damage to the equipment due to electrostatic charge, observe
the following precautions:
do not touch the contacts of the equipment, store and transport the equipment in
store static-sensitive components in appropriate
packages until they are installed in workstations,
Only remove components from antistatic packaging
Do not touch the contacts, conductors and circuits,
Before touching static sensitive components,
ground yourself securely.
There are several ways to ground. Before installing or working with
static-sensitive components, ground yourself with one or
in several ways:
Use a bracelet that is connected with a ground cable to the chassis of a grounded
a computer. Bracelets are flexible strips with a minimum resistance of 1 MΩ +/-
10% in grounding wires. To ensure reliable grounding, wear
bracelet on the wrist so that it fits snugly on the hand.
On standing workstations, attach grounding strips to the heels, toes, or
shoes. When working on conductive or dissipating static electricity
fasten grounding strips on both feet to the floor.
Use conductive tools.
Use the repairman’s portable kit, which includes a diffusion mat
ESD Prevention 147
Why ground the computer hardware
Such protective measures are advisory in nature. There is no specific document regulating the need for technological grounding of computer equipment.
The normative document with the most relevant materials substantiating the significance of such work is GOST R 50571.22 (Grounding of information processing equipment).
Important! After examining the power cable, through which the system unit is connected to the mains, you can notice three conclusions: the conclusions of the two supply wires (the first is zero, the second is phase), and the third wire is grounding. In the manufacture of a computer, it is necessary to ground it. Such a constructive decision of engineers should motivate users to ground their PCs.
The correct production of grounding work of computer equipment will allow:
- Eliminate the harmful effects of static electricity on the device. To do this, the user must protect the system unit from static. The potential of static electricity can reach several kW. Such a discharge can cause significant harm to the electronic components of a PC. The device of the system unit, in particular the internal arrangement of the power supply, is schematically equipped for the removal of impulse surges in the network and static voltages. The tap is implemented by means of special elements (diodes, suppressors, capacitors, etc.), which are located on the boards of the system unit. Electrical connection of all grounding points into one allows you to ground the device in two ways: ground the housing or connect the power supply to a grounded outlet using a ground wire.
- Prevent electric shock to PC user. For example, potential is created on the case and the following happens: a person simultaneously touches the heating device and the metal components of the PC case (unpainted). An indicator of 110 volts of voltage change on the device’s case does not represent a mortal danger, but nevertheless, the user will feel the discomfort from an impact. In the presence of grounding, such a discharge will go to earth through a conductor with negligible resistance.
- Reduce exposure to electromagnetic radiation. Modern production technologies of various computing equipment are implemented in accordance with the rules of safety standards. One of the main requirements of such documentation is to reduce the level of electromagnetic radiation of devices. Achieving a qualitative result by reducing the level of such an impact is impossible if the device is not grounded. Users with frequent and prolonged work with a PC may experience headaches and overwork.
- Reduce the impact of external interference. Crosstalk - additional voltage in the conductor that occurs due to spurious signals from different electromagnetic fields. In practice, this effect is especially clearly displayed when the home network is built. Crosstalk is one of the main causes of interference in the local network of the house (background and noise of the PC audio system). It is especially important to exclude such interference when the devices are intended for operation in the office. If all PC networks (home or office) are grounded, their performance will be much more efficient.
The removable side wall of the system unit must always be closed. A grounded, fully enclosed metal housing will serve as a protective shield, reducing the potential for negative effects on the user.
All existing requirements on how to ground the computer are based solely on recommendations on the correct implementation of work with computer technology.
How to properly ground the PC
Most owners are familiar with the principle of grounding a computer in an apartment or in a private house. But theory is not practice. Only a professional electrician with theoretical and practical experience in implementing such an electrical installation will be able to choose the optimal method of grounding the device. The specialist will determine which option is best for the grounding device of a particular equipment. A professional approach will increase the efficiency and duration of protection of the device in use for many years.
The correct options for grounding modern computer technology:
- The method of "pure zero". A direct connection to the fourth conductor of a three-phase wire is realized in the drive panel.
- The metal structure of the building is used as an earthing switch. Often mounted in buildings with reinforced concrete hollow panels.
- Option with a device of its own ground loop.
Note! The method of grounding a computer using a circuit is impractical to use due to complex practical implementation.
There is no fundamental difference in the production of the selected method for protecting the server, stationary PC or laptop. The main thing is that, as a result of grounding, the resistance between the "ground zero" and the grounding point (socket or PC case) does not exceed 4 - 10 Ohms. Check the compliance of such an indicator with a special device, for example Ф4103-М1.
Note! The specialist will take into account the structural features of the grounding equipment. An electrician will determine how to ground a stationary computer better, and how - a laptop. After all, the functionality of the technique is one, and the configuration of the elements is slightly different.
Despite the advantages of professional grounding technologies, many users use "folk methods" of grounding, the result of which is not only ineffective, but also dangerous.
How to ground the computer
The result of improper production of any type of wiring has very unpleasant consequences. To carry out work on the grounding of computer equipment, it is not enough to get acquainted only with its principle.
You need to know how to ground the PC:
- Connect the grounding contact to the zero in a two-pole socket.
- Ground the computer to the lightning conductor conductor. If the user touches the PC case when lightning strikes the lightning rod, a person will receive a current discharge.
- Use as a ground electrode various pipes of public communications.
Do not neglect the installation of protective equipment. Refusing to ground, the user will inevitably encounter problems associated with the repair of equipment. Repair will cost much more than installing a PC ground. In some cases, breakdowns can be significant - from the static, the memory slats can burn out or the touchpad on the laptop breaks down.