In industrial electrical networks, special protective devices are installed for the normal operation of equipment, but there are none in the interfloor distribution boards of residential buildings. Housing and communal services are not responsible for the breakdown of household electrical appliances due to poor operation of the electrical network. Therefore, the presence of complex electronics in the house requires mandatory protection from the harmful effects of power surges. To do this, you can use a surge protector or voltage stabilizer. Everyone decides for themselves what is best to use, but you need to at least approximately know what they are and what factors they protect from.
What kind of interference are there?
External influences are divided into high-frequency and pulsed. The latter, in turn, come in two classes:
- natural - lightning discharge near the power line (during a thunderstorm, all household electrical appliances should be turned off);
- man-made - the result of an accident at a substation, switching processes when connecting (disconnecting) a large number of consumers, wear and tear of electrical networks.
Pulse noise is common in industrial areas and urban areas. They occur in all networks and can reach a value of 6 kV in 10-6-10-9s. The equipment is protected from surges by connecting through surge protectors and voltage stabilizers.
The causes of RF interference are the same, only power tools and household electrical appliances are added to them. It is impossible to exclude them, since transmission occurs through wires and through space.
So which is better: a surge protector or a voltage stabilizer? Which is better for household appliances? When deciding these questions, consumers first look at price. In most cases, they confuse electrical protective devices, especially without separating them. Many people often take the wrong thing.
No. 5 – APC by Schneider Electric PMF83VT-RS
Price: 3,990 rubles
Experts agree that the model is one of the best not only in the brand’s lineup, but also in its segment as a whole. It is equipped with eight sockets, each of which has grounding, as well as protective curtains. The cord is quite long - three meters, the optimal indicator.
The protection here is well thought out - the filter ensures the safety of the data transmission line, filters electromagnetic interference and radio frequency noise, and protects against impulse noise and lightning strikes. There is a rotary wire clamp that rotates 180 degrees. Thus, you will not have problems with the placement of the device.
APC by Schneider Electric PMF83VT-RS
Surge filter functions
All people who use complex electronics cannot imagine how they can work without surge protectors. The device smoothes impulses and is a stabilization unit with a group of sockets. It consists of two parts: a voltage limiter and a filter. The first includes varistors - active resistances that change parameters depending on the voltage. They are switched on mainly between phase and zero. Protection of highly sensitive devices from high-frequency oscillations and pulses is carried out using an LC filter, which may also contain inductors.
The surge protector operates according to a classic single-phase circuit. Note! This circuit must include grounding for a three-wire power supply! If it is not there, the filter will also do its job, but worse. All impulse noise must go into the ground.
Varistor VDR1 is a variable semiconductor variable resistance that non-linearly changes characteristics simultaneously with voltage. It is installed at the input to suppress voltage pulses. The varistor takes them over without passing them on.
In addition to protection against interference, network filters provide for disconnecting consumers in the event of short circuits and overcurrent.
We have to decide the question: a surge protector or a voltage stabilizer - which is better. First, we pay attention to the price, which to some extent is an indicator of quality. Cheap devices do not save technology. But they can be used if you “bring them to mind” with your own hands.
There are many low-quality products on sale that do not have protective and filtering circuits. In this case, surge protectors serve only as extension cords or protect equipment from dangerous voltage increases. At the same time, you need to know that they do not serve for stabilization.
Selection rules
What types of voltage stabilizers are there, taking into account the principles of operation:
- servo drive (electromechanics);
- ferroresonance;
- relay;
- semiconductor (electronics);
- inverter
Ferroresonant ones operate on the principle of saturating the cores of the choke elements with magnetic fields. The design is simple, the device is static, the reliability of operation is maximum. Durability is good.
Electromechanical devices are equipped with a servo drive, which is responsible for the movement of current-collecting brushes. These brushes remove secondary voltage from the windings on the transformer. Please note that moving, rotating parts are always a vulnerability of the system. The price is low.
Do you need a voltage stabilizer for your computer? Of course, a relay model would be a good choice. Power relays, which are installed on the winding taps, are responsible for switching.
Inverter voltage stabilizer circuit
Electronic devices are almost completely devoid of mechanical elements in their design. The working elements are triacs or thyristors. The response is very fast, but the accuracy of voltage stabilization is not the highest. How to choose the right voltage stabilizer for a computer or other equipment of this type - with a margin. Its absence excludes the possibility of a clear correction.
Inverters are the most advanced type. The operation of such stabilizers is based on the conversion of variable voltage values into stabilized ones.
Purpose of a voltage stabilizer
The device is designed to maintain the network voltage at 220 V. If it exceeds a given value, it is equalized, and if it decreases, it is increased, as far as the transformer can handle it. If the external network is not working well, users pay more attention to it when choosing a voltage stabilizer or surge protector.
During emergency surges, the load is disconnected. In addition, pulse surges to the consumer during power switching are not missed.
Conclusions and recommendations
Having selected the appropriate type of protective mechanism, before purchasing you should familiarize yourself with its key parameters:
- For stabilizers: type (single- or three-phase), power, active and reactive loads, stabilization accuracy, starting current values.
- For network filters: maximum pulse load, types of fuses used, presence of a power-on indicator, quality and number of sockets.
Expert advice: It is not recommended to connect electrical devices with high starting current, such as a heat boiler or a high-power freezer, to surge protectors. You shouldn’t go cheap and buy a filter of unknown origin - overhauling home appliances that have suffered from wiring problems will result in large expenses.
Stabilizer circuits
In a stabilizer, the voltage is regulated in different ways. One of them is switching the secondary windings of the transformer.
The voltage change is made by electronic keys controlled by the processor. Data comes from the sensor and is switched using an electronic switch on thyristors.
Parametric stabilizers use the phenomenon of avalanche breakdown on zener diodes, when the voltage remains constant despite a significant change in current. To amplify the power, the load is connected through one or more transistors.
Capacitors are used as high-frequency filters in the circuit. A stabilizer is a complex device that may include a surge protector.
The input resistor allows you to keep the transistor open and also maintains the zener diode in the active region.
The stabilizer is selected according to the power of the consumers. Nowadays, electronics are used everywhere, for example, in control units for energy-saving lamps. Therefore, it is needed not only for computers, but also for lighting systems. If it is used for electric motors, you should know that the starting current of the latter is several times higher than the rated current. Despite the fact that stabilizers allow short-term overloads, here a larger power reserve should be taken.
No. 4 – Brennenstuhl Alu-Office-Line 60.000A 4
Price: 5,500 rubles
One step away from the top pedestal, where the best surge protectors are collected, is the Brennenstuhl Alu-Office-Line model. In addition to the stylish design, which looks even more impressive in real life than in the photo, the model has two USB ports for charging gadgets. True, there are only four sockets here, which may scare off many. True, they are of the highest quality and ensure tight contact with the plug.
Many people note in reviews that the model is capable of protecting devices from impacts with a maximum leakage current of up to 60,000A. The cable routing is well thought out and ensures ergonomic placement of the filter. It is noteworthy that the sockets are located at an angle of 45 degrees and are suitable for angled plugs.
Brennenstuhl Alu-Office-Line 60.000A 4
Uninterruptible power supply (UPS)
In a specialized store, sellers may vie with each other to offer a stabilizer, a surge protector and a UPS. What is better to buy is difficult to decide right away given the existing large selection of models with different names and properties.
Many people purchase a UPS to eliminate one possible fault in the network - a sudden loss of voltage, in order to correctly shut down the operation of electronic devices. Imported models are designated UPS. It is advisable to purchase them with a stabilizer function to eliminate radio frequency and electromagnetic distortion and interference.
If the supply voltage disappears or decreases beyond the required range, the UPS switches to working through batteries. Depending on the model used, the operating time of an independent source can reach several minutes or hours. The device is selected according to the power of the equipment being protected.
An important characteristic of a UPS when operating on battery power is the output voltage shape. For cheap devices it is rectangular, and in frequency and amplitude it is equal to the mains sinusoidal voltage.
No. 3 – Energenie EG-PMS2-LAN
Price: 7,000 rubles
Many professionals recommend this surge protector if you are looking for a device that can provide excellent protection for your computer. This is an advanced model, which is equipped with four sockets with grounding and curtains. It is noteworthy that turning them on and off depends on events occurring on the computer - starting or shutting down Windows, turning on certain programs. Thus, unused devices will not consume electricity.
There is an RJ-45 network interface, which is the main distinguishing feature of the filter from previous competitors in the rating. Due to this, you can program all four sockets individually and control them from your smartphone, wherever you are.
Energenie EG-PMS2-LAN
Multifunctional UPS
The UPS protects devices not only during shutdown, but also when voltage drops below an acceptable threshold by switching to batteries. Intermittent operation will shorten battery life. It is advisable to additionally connect a voltage stabilizer in front of the uninterruptible power supply. For some models this is not necessary. A modern UPS may contain a built-in filter or voltage stabilizer.
The voltage of a modified (rectangular) sinusoid cannot be measured correctly with a conventional voltmeter. Readings will differ significantly from actual values.
Is it necessary to use protective equipment at all?
Modern expensive electrical equipment and equipment are very sensitive to various factors that cause failures in the electrical network, which is what domestic energy networks are famous for. The most vulnerable components and parts are microcircuits, power supplies, motors, etc. Long surges, low or high voltage cause household appliances to operate in overload mode. This significantly reduces the service life or leads to premature failure of electrical appliances.
Advice. The use of means of protection against unstable operation of electrical networks not only protects equipment from breakdowns, but also saves money on the purchase of expensive replacements for failed equipment.
What is the difference between a voltage stabilizer and a surge protector?
It is preferable to use a stabilizer due to the fact that protection is carried out at several levels. It may include a surge protector as a separate part (for example, products from Sven). By itself, it does not correct undervoltage, which negatively affects the longevity of devices.
When it increases, the fuse in the device burns out and will have to be replaced. But models are constantly being improved, and it is advisable to correctly determine which surge protector is better based on their characteristics.
The stabilizer will gently turn off the power from the network, which can then be easily restored. It is preferred because the price of a mid-level model is the same as a high-quality surge protector. The power reserve of any protective device is taken at the level of 20-30%.
The purchase of a high-quality stabilizer is justified in the following cases:
- unstable operation of the external network (relevant for rural areas);
- the total cost of household appliances should be significantly higher.
No. 10 – SVEN SF-05PL
Price: 820 rubles
A good filter at an affordable price. The cable length here is decent - three meters, there are five sockets. A distinctive feature of the solution, due to which it looks more interesting than most competitors, is the presence of individual switches. It’s not even worth mentioning how convenient it is. Another advantage is plastic, which does not emit unpleasant odors during operation, since the body does not heat up.
The inexpensive device copes with its task perfectly well; many buyers report in reviews that it has been serving them faithfully for several years now. Considering how much the filter costs, it has no significant disadvantages.
SVEN SF-05PL
