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. 9 – InterStep SP-306W
Price: 770 rubles
Our 2022 surge protector rankings move on. The budget model has 6 sockets, as well as two USB ports. The presence of the latter will allow you to charge smartphones and other gadgets without occupying an outlet. However, its distinguishing feature is the enhanced surge protection unit. The manufacturer claims that thanks to it the filter is 10 times more reliable than competitors at the same price.
Another advantage of the cheapest representative of the selection is considered to be its ergonomic design, which allows you to hide wires from connected devices. Most often in reviews, owners complain about the length of the cable - it is only 1.8 meters.
InterStep SP-306W
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.
Types of 220 volt network stabilizers
Each electrical device operates within a certain voltage range. According to the standards, deviation from the normal voltage of 220 V is allowed no more than ten percent. Both increased and decreased voltage are dangerous for devices. In the first case, the power supply quickly fails; in the second, the power supply operates at maximum power, which also leads to its failure. If voltage drops exist, installing a stabilizer is simply necessary.
In the production of stabilizers, a different approach is used to ensure stable voltage. But at the same time, any such device is required to maintain the voltage within the permissible range when it deviates. If the deviation is a large number, the stabilizer will turn off and interrupt the supply of electricity to the connected electrical appliance. Depending on the type of electrical wiring, they can be single-phase or three-phase. Based on the principle of operation, they are distinguished:
- Relay. Such devices are based on a multi-winding transformer and powerful relays. In case of deviations from the norm, the winding is automatically switched through a power relay. This type is characterized by a low price. The main drawback is stepwise adjustment of the voltage value and distortion of the output signal, i.e. the output is no longer a pure sine wave.
- Servo driven. Another name for them is electromechanical. They operate using an autotransformer with a control system that controls the electric motor. They are characterized by low price, smooth adjustment, small size and good output signal shape. The disadvantages include noise and low response time.
- Inverter. They use double conversion, alternating current into direct current and again into alternating current. For this, a complex circuit with a microcontroller is used. They can operate over a wide range of input voltages with a high speed of response to changes in signal magnitude. They provide protection from any type of interference, but are also the most expensive devices.
- Ferroresonant . They have not received much use due to their heavy weight and noise during operation, although they have high adjustment accuracy. They work on the ferroresonance effect.
- Thyristor. The principle of operation is the same as that of the relay type, but instead of noisy relays, semiconductor elements, thyristors, are used. This type is characterized by fast response and high efficiency. At the same time, they are completely silent, but the price is not much cheaper than inverter stabilizers.
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.
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.
#7 – Pilot Pro GP
Price: 1,400 rubles
Surge filter from a domestic brand. His presence is not due only to patriotic feelings. The device can show the owner that he has inserted the plug the wrong way. There is also an inverted phase indication. The main advantage is protection. The device guarantees the safety of equipment in the event of power surges and impulses. In the event of a short circuit, the fuse will burn out, but it can be replaced.
There are six sockets in total, with two for flat plugs. The filter housing is made of impact-resistant plastic, and the tires are made of metal. This ensures tight contact of the plug in the sockets. For ease of placement of the wire, a special removable element is provided. The cable length is a controversial point - 1.8 meters. Otherwise, there are no shortcomings; in terms of price-quality ratio, this is an excellent option.
Pilot Pro GP
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.
Power supply
It is impossible not to mention another device that protects equipment from power outages. This is an uninterruptible power supply (UPS). Its main component is the battery. When the power supply is turned off, the control circuit switches to the battery and consumers continue to receive energy.
This makes it possible to shut them down correctly, which is especially important for a computer: it is important for the user to save the results of their work, and for the operating system to correctly end the session.
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.
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.
Protection of household appliances
SVEN surge protectors
Engineers of modern household appliances focus on compactness and efficient energy consumption. The approach has a minus - sensitivity to voltage drops. As a result, the owner receives an unpleasant bill for repairs and frayed nerves.
The standard voltage in the network should be 220V, GOST provides for an error of 10%. In theory, the network should not be less than 198 and more than 240 V, but in practice the network varies from 35 to 400 volts. Even equipment protected from extremes will not be able to withstand such a load.
When there is a power surge, the refrigerator and computer are the first to fail. The power supply provides minimal protection for such situations. Most often, everything ends with burnt coils and swollen capacitors. The same goes for flat screen TVs and monitors.
With small household appliances everything is simple, but with refrigerators and washing machines things are worse. If the equipment was plugged in at the time of the overvoltage, the motor often fails. Burnt parts must only be replaced. As a result, repairs are much more expensive than a regular voltage stabilizer or filter.
