In modern housing, great importance is attached to protecting the power grid from strong overvoltages. To do this, network stabilizers are used to smooth out sharp fluctuations, but differing in a number of disadvantages. It is much more profitable to use inexpensive and compact 220V voltage relays for the home, providing reliable protection for household networks. These devices, abbreviated as ILV, are mounted in the distribution panel and do not need significant space within the apartment.
The principle of operation and functionality
The principle of operation of the device, known to most fans as a voltage limiter 220V, can be understood after familiarizing yourself with its device. The structure includes the following nodes:
- electronic control module, adjustable for lower and upper limits;
- driver signal driver;
- electromagnetic relay that trips the device when the setpoint is exceeded.
When the voltage in the network reaches one of the limit levels, the electronics generates a control signal that supplies power to the monitoring relay. It works and de-energizes the line, protecting household appliances connected to outlets.
The functionality of such products in comparison with the same stabilizer is significantly expanded:
- Two thresholds can be set (upper and lower).
- The devices have LED indicators that are built into the front panel and provide control of the presence of voltage at the input and output.
- A liquid crystal display is provided on which the values of the main parameters of the mains power are recorded.
The listed features significantly facilitate the operation of protective equipment installed in an apartment or in a country house.
Classification and types
Known ILV types differ in the type of food used in the home, according to which they are single-phase or three-phase. 220V power supply relays are installed in urban housing, and their three-phase counterparts are used in offices or enterprises. Often they are found in private houses, to which a branch from the 380 Volt line is connected (three-phase power supply).
According to the method of connecting to the serviced line, the known models of the 220V mains voltage monitoring relay for the home are divided into the following types:
- adapters plugged into a regular outlet;
- extension cords having several sockets (from 1 to 6);
- devices mounted in a dashboard on a DIN rail.
The first two positions are transitional devices that protect individual household consumers. In this they fundamentally differ from the ILV installed in the control cabinet. Whole groups of electrical appliances can be connected to them.
Advantages and disadvantages of products included in the outlet
Before you purchase a voltage monitoring relay in a power outlet, it is important to evaluate its merits justifying the purchase.
- Ease of installation, compactness and mobility (the ability to include anywhere);
- relatively low cost;
- attractive design that does not violate the interiors of the premises;
- universality: admissibility of use for protection of an individual consumer or several loads at once.
Adapters and extension cords are well designed. Their appearance meets the most demanding needs and does not introduce visible violations into the interiors of rooms. The disadvantages include the lack of a number of options available for devices mounted on a DIN rail.
Which type is preferable
If the user is concerned about the safety of an expensive model of the refrigerator, for example, and all other devices are already protected by a stabilizer, it is more convenient to purchase a “socket-plug” type sample.
In this case, the installation of a common automatic device will be unnecessary, as it will lead to unjustified costs. This option is more suitable for residents of urban apartments who do not want to spend money on installing ILV in the switchboard (for this you will have to invite an electrician).
Regardless of the operating conditions of the monitoring relay, it should be understood that installing several devices in a power outlet will cost more than one in a dashboard.
When there is no stabilizer in the house, and its owner wants to reliably protect kitchen and room equipment, it is wiser to choose a device mounted on a DIN rail. When installing several relays - one for each protected line - the possibility of breakdown of expensive equipment is completely eliminated. They are ideal for a private house, where they can control a three-phase network.
Features of the ILV installation
The general procedure for mounting a relay in an electrical cabinet is determined by the requirements of current standards (PUE, in particular). Each specific ILV model can be installed in accordance with the functions performed by it. The following options for installing the relay in the wiring line are possible:
- placement immediately after the electric meter (this method is considered classic);
- connection together with an RCD and a linear machine, which expands the functionality of the device;
- installation to an electric meter, which allows the metering device to be protected against overvoltage.
The latter option is possible only after obtaining permission from representatives of Energosbyt.
Depending on the method of connecting to the load, various ILV samples are installed either according to the direct connection to the load or through the power contacts of the magnetic starter. The second option significantly expands the capabilities of the device for the load current.
Setting Modes
The threshold values of the ILV are set using several potentiometers on a graduated scale, carried out together with the handles on the front panel.
In some samples, buttons are used to set the response limits.
The step with which the lower and upper bounds are set for most ILV samples is one Volt. The correct setting of the desired parameter is controlled by the indicator board available on the front panel of the device.
On some models, there is another regulator that sets the time the device returns to its original state, the moment the load is reconnected to the power circuit. It can be set in a wide range of values from a few seconds to 10 minutes.
Description of popular models
The connection and configuration schemes of most models offered by domestic manufacturers have much in common, they can differ only in details.
Devices under the brand Bison
Protective devices of this series are included in the power supply circuit in two ways:
- simplified internal connection;
- together with an RCD and a circuit breaker.
In the first case, the load is connected directly to the output of the device, and in the second case, the control circuit is closed via RCD and AB. Such inclusion of the Bison allows you to protect the line not only from voltage surges, but also from current leaks.
The devices have various versions, differing in rated currents (25-63 Amperes). The upper threshold is from 220 to 280 in increments of 1 Volt, and its lower value is from 120 to 210 Volts. The re-inclusion time in the line varies from 3 to 600 seconds. Adjustment step - 3 seconds.
PH series
The PH-113 model is switched on after the electric meter and allows manual setting of the lower and upper thresholds, which are displayed on the display integrated in the front panel.The device is able to automatically connect the supply network when restoring its parameters after strong power surges.
For the normal operation of devices of this series, a power margin of at least 20% is required.
In addition to the limit values, the indicator displays network parameters when the consumer is turned off, as well as the time remaining before switching on. The rated current is 32 amperes; if desired, it can be increased by installing a magnetic starter.
UZM Series
The UZM-51M device, installed immediately after the electric meter, is designed for a rated current of up to 63 Amperes and immediately occupies 2 modules on a DIN rail. Its standard width is 35 mm. The maximum set point for the upper voltage limit is 290 Volts. The lower overvoltage threshold is 100 Volts.
Manual restart time set by the user can take two fixed values - 10 seconds and 6 minutes. UZM series devices can be installed in networks with any grounding system: TN-C, TN-S or TN-C-S.
Devices from DigiTOP
The V-protektor ILVs are used only for surge protection. They are rated for rated currents from 16 to 63 amperes. The upper threshold is set in the range from 210 to 270, and the lower - from 120 to 200 volts. The time to automatically restore the on state is from 5 to 600 seconds. The three-phase device V-protektor 38 is designed for a maximum current of not more than 10 amperes.
Devices brand ABB
The ABB CM series, popular on the market, allows you to adjust the threshold in a wide range of values (from 24 to 240 Volts in single-phase and from 320 to 430 Volts in three-phase circuits). Recovery time for most models is from 1 to 30 seconds.
