It is a low-voltage switching device designed to remotely turn off and turn on an electrical load in a network with a voltage of up to 1000 Volts. This device can be used both in industry and at home, so it is important to know about the nuances of choosing its characteristics. In this article we will tell you how to choose a magnetic starter based on power, current and other parameters.

Functionality

Below are typical functions performed by magnetic starters, which are far from exhaustive of their applications:

• Control of asynchronous electric motors in drives of industrial mechanisms.
• Turning on external (street) city lighting, external and internal lighting of industrial facilities.
• Switching of electric heating devices (heating elements or infrared heaters) of electric heating systems.
• Use as triggers in industrial automation circuits.

The choice of magnetic starters is made when designing control and automation circuits, or during their repair, when to replace an outdated or missing device it is necessary to select its analogue.

Criterias of choice

When choosing the required electrical device, its technical characteristics and design features are considered. Let's look at the main ones.

Rated voltage of switched circuit. Most often, magnetic starters are used to start asynchronous motors with a squirrel cage rotor at an industrial voltage of 220/380 Volts. It is for this choice that most manufactured models of switching devices are designed. When using devices for 380/660 Volt electric motors, which are much less common, you must select a starter of the appropriate voltage.

Rated current of main contacts. Comparing the current of the connected load with the rated current of the switching device is one of the first actions when choosing the latter. Magnetic starters produced in the Russian Federation according to Soviet GOSTs, for example PML, are conventionally classified according to values ​​​​corresponding to the rated current of the device. Below is a table of the ratios of values ​​and rated currents. Using it, you can correctly select the magnetic starter by current or power by recalculating using the formula.

Magnitude	O	I	II	III	IV	V	VI
I nom	6.3 A	10 A	25 A	40 A	63 A	100 A	160 A

Products from foreign manufacturers are represented by a wide selection of contactors of various designs for various rated currents.

Switching wear resistance. This characteristic reflects the number of operations guaranteed by the manufacturer. There are 3 wear resistance classes: A, B and C. Class A is the highest and guarantees from 1.5 to 4 million cycles of operation of the magnetic starter. Class B models are guaranteed to operate from 0.63 to 1.5 million cycles. Class B is the lowest and is characterized by from 0.1 to 0.5 million operation cycles.

Mechanical wear resistance. An equally important characteristic that displays the number of cycles of turning on/off the device without repairing or replacing its parts. In this case, switching on and off must be carried out without load (when there is no current in the circuit). Mechanical wear resistance can be from 3 to 20 million operation cycles.

To power three-phase electric motors, devices with three poles are used. This is the most common execution. However, a number of situations arise when it is necessary to select a device with a different number of poles. For example, when the load is lighting circuits or electric heating devices. In this case, it is convenient to choose a switching device from the line of contactors from foreign manufacturers, represented by a wide variety of designs.

Rated coil voltage. Magnetic starters used in control circuits of electrical equipment are most conveniently used with coils for the same voltage as the switched load. For this reason, the most common options are those with 220 or 380 Volt coils. When constructing various types of automatic circuits, for a number of reasons it may be necessary to use control coils at a different voltage level. This is due to the use of relays, sensors or other components in these circuits that are designed for a specific supply voltage. In this case, in the lines of domestic and foreign manufacturers there is a choice of options for powering coils with any voltage from the nominal range from 9 Volts and higher (9, 12, 24, 36, 110, 220 or 380 V).

Number and characteristics of auxiliary contacts. In addition to the main power contacts that switch the main electrical circuits of the load, magnetic starters are equipped with auxiliary contacts that operate synchronously with the main one. These contacts are intended for switching control circuits, interlocking, powering signal lamps, relay coils and other auxiliary devices. Auxiliary contacts can be of two types - normally open and normally closed. The former are open when the control coil is de-energized and close when the electromagnetic starter is triggered, while for the latter everything happens the other way around. The need to select a certain number of additional contacts of one type or another is determined by the circuit in which the device is used.

For example, to organize the simplest control of a mechanism using a two-button post, it is enough to select an option with one pair of normally open auxiliary contacts that pick up the control coil when the “Start” button is pressed. There are options for closed-type magnetic starters, equipped with start and stop buttons on the housing. If it is necessary to signal the state of the mechanism, you need to select a starter that has two more pairs of contacts. Normally closed ones power the “Off” signal lamp, normally open ones power the “On” lamp.

Availability of reverse. If you need to choose a magnetic starter to control a reversible motor, give preference to a reversible model, the housing of which contains two separate starters connected to each other.

Availability of protection. In the basic version, the magnetic starter is not equipped with protection for connected electrical equipment. A protection module with a thermal relay is available as an option and can be selected based on the required characteristics. You can learn more about this from our article.

In addition to the criteria listed above, it is necessary to choose the right climatic design and products. The methodology for this selection is the same as for any electrical equipment. For example, if the starter will be placed in a protected cabinet, you can select the IP20 protection degree. If the conditions for placing the device are unfavorable (high dust, humidity, etc.), we recommend choosing a magnetic starter in a housing with a protection degree of IP54 or IP65.

Expert advice

These are all the most important criteria for choosing a magnetic starter. If you have any questions or you haven’t found the information you need, write in the comments below the post, we, in turn, will try to help you find the answer you need!

A magnetic starter is a key element in almost every electrical circuit. With the help of a contactor, consumers are connected, loads are controlled remotely and other switching switches are carried out. Depending on the voltage of the control network, they also differ in control voltage: 12, 24, 110, 220, 380 volts. Typically, for connecting three-phase and other loads, there are contacts L1, L2, L3 and auxiliary NO or NC. The small-sized starter is controlled manually or by various automatic devices, such as time relays, light relays, and others. Below we will look at some diagrams for connecting a magnetic starter for 220 and 380 volts, which may be useful at home.

Overview of options

In manual mode, activation is carried out from a push-button station. The start button opens the contact to close, and the stop button works to open. The connection diagram for a self-retaining magnetic starter is as follows:
Let's consider the operation of the on and off circuits of a magnetic contactor. A push-button station of two buttons, when you press START, the phase comes from the network through the STOP contacts, the circuit is assembled, the starter retracts and closes the contacts, including the additional NO, which is parallel to the START button. Now, if you release it, the magnetic starter continues to operate until the voltage disappears or the motor protection P is triggered. When STOP is pressed, the circuit is broken, the contactor returns to its original position and the contacts open. Depending on the purpose, the power supply to the coil can be 220V (phase and zero) or 380V (two phases), the operating principle of the control circuits does not change. Switching on a three-phase electric motor with a thermal relay through a push-button station looks like this:

In the end it looks something like this, in the picture:

If you want to connect a three-phase motor through a magnetic starter with a 220-volt coil, you need to make the switch according to the following wiring diagram:

Using three buttons on the control panel, you can organize the reverse rotation of the electric motor.


If you look closely, you can see that it consists of two elements of the previous diagram. When you press START, the KM1 contactor turns on, closing the NO KM1 contacts, becoming self-retaining, and opening the NC KM1, excluding the possibility of turning on the KM2 contactor. When you press the STOP button, the chain is disassembled. Another interesting element of the three-phase reversible connection circuit is the power section.


On the KM2 contactor, phases L1 are replaced by L3, and L3 by L1, thus changing the direction of rotation of the electric motor. In principle, this circuitry for controlling three-phase and single-phase loads completely covers household needs and is easy to understand. You can also connect additional automation elements, protection, limiters. They all need to be considered separately for each specific device.

Using the above diagram for connecting a magnetic starter, you can organize the opening of a garage door by introducing additional limit switches into the circuit, using NC contacts in series with NC KM1 and NC KM2, limiting the movement of the mechanism.

Connection Instructions

The easiest connection option is through a button. In this case, you need to act as shown in the video:

We connect the starter via a push-button post (without reverse)

In an example with an engine it looks like this:

380 Volt electric motor control

You can connect the motor using a reverse circuit as follows:

Turning on the engine via three buttons

Using this principle, you can independently connect the device to a 220 and 380 volt network. We hope that our instructions for connecting a magnetic starter with diagrams and detailed video examples were clear and useful for you!

To remotely turn on the equipment, a magnetic starter or magnetic contactor is used. We will look at how to connect a magnetic starter using a simple circuit and how to connect a reversing starter in this article.

The difference between a magnetic starter and a magnetic contactor is how much load power these devices can switch.

The magnetic starter can be “1”, “2”, “3”, “4” or “5” magnitude. For example, the second magnitude starter PME-211 looks like this:

The names of the starters are deciphered as follows:

• The first sign P is the Starter;
• The second sign M is Magnetic;
• The third character E, L, U, A... is the type or series of the starter;
• The fourth digital digit is the starter size;
• The fifth and subsequent digital characters are the characteristics and types of the starter.

Some characteristics of magnetic starters can be seen in the table

The differences between a magnetic contactor and a starter are very conditional. The contactor performs the same role as the starter. The contactor makes similar connections as the starter, only the electrical consumers have greater power, and accordingly the dimensions of the contactor are much larger, and the contacts of the contactor are much more powerful. The magnetic contactor has a slightly different appearance:

The dimensions of contactors depend on its power. The contacts of the switching device must be divided into power and control. Starters and contactors must be used when simple switching devices cannot control large currents. Due to this, the magnetic starter can be placed in power cabinets next to the power device that it connects, and all its control elements in the form of buttons and push-button switching stations can be located in the user’s work areas.
In the diagram, the starter and contactor are indicated by the following schematic sign:

where A1-A2 is the starter electromagnet coil;

L1-T1 L2-T2 L3-T3 power contacts to which the three-phase power voltage (L1-L2-L3) and the load (T1-T2-T3) are connected, in our case an electric motor;

13-14 contacts blocking the engine control start button.

These devices can have solenoid coils for voltages of 12 V, 24 V, 36 V, 127 V, 220 V, 380 V. When an increased level of safety is required, it is possible to use an electromagnetic starter with a 12 or 24 V coil, and the load circuit voltage can have 220 or 380 V.
It is important to know that connected starters for connecting a three-phase motor can provide additional safety in case of accidental loss of voltage in the networks. This is due to the fact that when the current in the network disappears, the voltage on the starter coil disappears and the power contacts open. And when the voltage returns, there will be no voltage in the electrical equipment until the “Start” button is activated. There are several circuits for connecting a magnetic starter.

Standard switching diagram for magnetic starters

This starter connection diagram is required in order to start the engine through the starter using the “Start” button and de-energize this engine with the “Stop” button. This is easier to understand if you divide the circuit into two parts: the power circuit and the control circuit.
The power part of the circuit should be powered with a three-phase voltage of 380 V, having phases “A”, “B”, “C”. The power part consists of a three-pole circuit breaker, power contacts of the magnetic starter “1L1-2T1”, “3L2-4T2”, “5L3-6L3”, as well as an asynchronous three-phase electric motor “M”.

The control circuit is supplied with 220 volt power from phase “A” and to the neutral. The control circuit diagram includes the “Stop” button “SB1”, “Start” “SB2”, the coil “KM1” and the auxiliary contact “13HO-14HO”, which is connected in parallel with the contacts of the “Start” button. When the circuit breaker of phases “A”, “B”, “C” is turned on, the current passes to the contacts of the starter and remains on them. The supply control circuit (phase “A”) passes through the “Stop” button to contact 3 of the “Start” button, and in parallel to the auxiliary contact of the 13HO starter and remains there on the contacts.
If the “Start” button is activated, voltage comes to the coil - phase “A” from the starter “KM1”. The starter electromagnet is triggered, the contacts “1L1-2T1”, “3L2-4T2”, “5L3-6L3” are closed, after which a voltage of 380 volts is supplied to the engine according to this connection diagram and the electric motor begins to operate. When the “Start” button is released, the starter coil supply current flows through contacts 13HO-14HO, the electromagnet does not release the starter power contacts, and the engine continues to operate. When the “Stop” button is pressed, the power supply circuit of the starter coil is de-energized, the electromagnet releases the power contacts, voltage is not supplied to the engine, and the engine stops.

You can also watch the video to see how to connect a three-phase motor:

Switching diagram for magnetic starters via a push-button post

The circuit for connecting a magnetic starter to an electric motor through a push-button post includes the post itself with the “Start” and “Stop” buttons, as well as two pairs of closed and open contacts. This also includes a starter with a 220 V coil.

Power for the buttons is taken from the power contact terminals of the starter, and the voltage reaches the “Stop” button. After that, it passes through the jumper through the normally closed contact to the “Start” button. When the Start button is activated, the normally open contact will be closed. Disconnection occurs by pressing the “Stop” button, thereby disconnecting the current from the coil and after the action of the return spring, the starter will turn off and the device will be de-energized. After completing the above steps, the electric motor will be turned off and ready for subsequent start-up from the push-button station. In principle, the operation of the circuit is similar to the previous circuit. Only in this circuit the load is single-phase.

Reversible switching circuit for magnetic starters

The connection diagram for a reversible magnetic starter is used when it is necessary to ensure rotation of the electric motor in both directions. For example, a reversing starter is installed on an elevator, lifting crane, drilling machine and other devices that require forward and reverse movement.

The reversing starter consists of two ordinary starters assembled according to a special circuit. It looks like this:

The connection diagram for a reversible magnetic starter differs from other circuits in that it has two completely identical starters that operate alternately. When the first starter is connected, the engine rotates in one direction, when the second starter is connected, the engine rotates in the opposite direction. If you look closely at the diagram, you will notice that with variable connection of starters, two phases change places. This causes the three-phase motor to rotate in different directions.

To the starter available in the previous diagrams, a second starter “KM2” and additional control circuits for the second starter were added. The control circuits consist of a button “SB3”, a magnetic starter “KM2”, as well as a modified power unit for supplying power to the electric motor. The buttons when connecting a reversing magnetic starter are named “Right”, “Left”, but may also have other names, such as “Up”, “Down”. To protect the power circuits from short circuits, two normally closed contacts “KM1.2” and “KM2.2” were added to the coils, which were taken from additional contacts on the magnetic starters KM1 and KM2. They do not allow both starters to turn on at the same time. In the diagram above, the control and power circuits of one starter are one color and the other starter is a different color, making it easier to understand how the circuit works. When the automatic switch “QF1” turns on, phases “A”, “B”, “C” go to the upper power contacts of the starters “KM1” and “KM2”, and then wait there for switching on. Phase “A” powers the control circuits from the circuit breaker, passes through “SF1” - thermal protection contacts and the “Stop” button “SB1”, goes to the contacts of the “SB2” and “SB3” buttons and remains waiting for a press on one of these buttons . After pressing the start button, the current moves through the auxiliary starting contact “KM1.2” or “KM2.2” to the coil of the starters “KM1” or “KM2”. After this, one of the reversing starters will work. The engine starts to rotate. To start the engine in the opposite direction, you need to press the stop button (the starter will open the power contacts), the engine will turn off power, wait until the engine stops and then press another start button. The diagram shows that the “KM2” starter is connected. At the same time, its additional contacts “KM2.2” opened the power circuit of the coil “KM1”, which will prevent accidental connection of the starter “KM1”.

Magnetic starters are intended mainly for remote control of three-phase asynchronous electric motors with a squirrel-cage rotor, namely:

• for starting by direct connection to the network and stopping (turning off) the electric motor (irreversible starters),

• for starting, stopping and reversing the electric motor (reversing starters).
  

Besides, starters with thermal relay They also protect controlled electric motors from overloads of unacceptable duration.

Open magnetic starters designed for installation on panels, in closed cabinets and other places protected from dust and foreign objects.

Protected magnetic starters Designed for indoor installation where the environment does not contain a significant amount of dust.

Dust-splash-proof magnetic starters Designed for both indoor and outdoor installations in places protected from sunlight and rain (under a canopy).

PML series magnetic starter

Magnetic starter device

Magnetic starters have magnetic system, consisting of an armature and a core and enclosed in a plastic case. Placed on the core retractor coil. A traverse slides along the guides of the upper part of the starter, on which the armature of the magnetic system and bridges of main and blocking contacts with springs.

The operating principle of the starter is simple: when voltage is applied to the coil, the armature is attracted to the core, normally open contacts close, normally closed contacts open. When the starter is turned off, the opposite picture occurs: under the action of return springs, the moving parts return to their original position, while the main contacts and normally open block contacts open, and normally closed block contacts close.

Reversing magnetic starters are two conventional starters mounted on a common base (panel) and having electrical connections that provide electrical interlock through normally closed blocking contacts of both starters, which prevents one magnetic starter from turning on when the other is turned on.

See the most common circuits for connecting a non-reversible and reversible magnetic starter here:. These circuits provide zero protection using a normally open contact of the starter, which prevents the starter from spontaneously turning on when voltage suddenly appears.

Reversing starters can also have mechanical locking, which is located under the base (panel) of the starter and also serves to prevent the simultaneous activation of two magnetic starters. With electrical blocking through the normally closed contacts of the starter itself (which is provided by its internal connections), reversing starters operate reliably without mechanical blocking.

Reversing magnetic starter

Motor reverse using a reversing starter, it is carried out through a preliminary stop, i.e. according to the scheme: turning off the rotating engine - complete stop - turning on reverse rotation. In this case, the starter can control an electric motor of the appropriate power.

In the case of using reversing or braking of the electric motor by back-switching, its power should be selected below 1.5 - 2 times the maximum switching power of the starter, which is determined by the state of the contacts, i.e. their wear resistance when operating in the applied mode. In this mode, the starter must operate without mechanical interlock. In this case, electrical interlocking through the normally closed contacts of the magnetic starter is required.

Magnetic starters of protected and dust-splash-proof versions have a shell. Starter shell The dust-splash-proof design has special rubber seals to prevent dust and water splashes from entering the starter. The inlet holes into the shell are closed with special samples using seals.

Thermal relays

A number of magnetic starters are equipped with thermal relays, which provide thermal protection of the electric motor against overloads of unacceptable duration. Adjustment relay setting current- smooth and is produced by the setpoint regulator by turning it with a screwdriver. Look here about. If it is impossible to implement thermal protection in intermittent operating mode, magnetic starters without a thermal relay should be used. Thermal relays do not protect against short circuits

Thermal relays

Scheme of direct start and protection of an asynchronous motor with a squirrel-cage rotor (a), (b) – starting characteristic of the motor (1) and protective characteristic of the thermal relay (2)

Installation of magnetic starters

For reliable operation, magnetic starters must be installed on a flat, rigidly reinforced vertical surface. Starters with thermal relays are recommended to be installed at the lowest difference in air temperature between the starter and the electric motor.

To prevent false alarms, it is not recommended to install starters with thermal relays in places subject to shocks, sharp shocks and strong shaking (for example, on a common panel with electromagnetic devices with rated currents of more than 150 A), since when turned on they create large shocks and shocks .

To reduce the influence on the operation of the thermal relay of additional heating from extraneous heat sources and to comply with the requirement that the air temperature surrounding the starter is not allowed to exceed 40 °C, it is recommended not to place thermal devices (etc.) next to magnetic starters and not to install them with a thermal relay in the upper, most heated parts of the cabinets.

When connecting one conductor to the contact clamp of a magnetic starter, its end must be bent into a ring- or U-shape (to prevent distortion of the spring washers of this clamp). When connecting two conductors of approximately equal cross-section to a clamp, their ends should be straight and located on both sides of the clamping screw.

The connecting ends of copper conductors must be tinned. The ends of stranded conductors must be twisted before tinning. When connecting aluminum wires, their ends must be cleaned with a fine file under a layer of CIATIM lubricant or technical petroleum jelly and additionally coated with quartz vaseline or zinc-vaseline paste after stripping. The contacts and moving parts of the magnetic starter must not be lubricated.

Before starting the magnetic starter it is necessary to carry out an external inspection and make sure that all its parts are in good working order, as well as that all moving parts can move freely (by hand), check the rated voltage of the starter coil with the voltage supplied to the coil, make sure that all electrical connections are made according to the diagram.

When using starters in reverse modes, by pressing the movable crossbar by hand until the main contacts touch (start to close), check for the presence of a solution of normally closed contacts, which is necessary for reliable operation of the electrical interlock.

When the magnetic starter is turned on, a small electromagnet hum, characteristic of laminated magnetic systems.

Caring for magnetic starters during operation

Maintenance of starters should consist, first of all, of protection of the starter and thermal relay from dust, dirt and moisture. Make sure that the terminal screws are tightly tightened. It is also necessary to check the status of the contacts.

The contacts of modern magnetic starters do not require special care. The wear life of the contacts depends on the conditions and operating mode of the starter. Stripping contacts of starters is not recommended, since the removal of contact material during stripping leads to a decrease in the service life of the contacts. Only in some cases of severe melting of the contacts when the emergency mode of the electric motor is turned off is it possible to clean them with a small needle file.

If, after long-term operation of the magnetic starter, a buzzing sound of a rattling nature appears, it is necessary to clean the working surfaces of the electromagnet from dirt with a clean rag, check for the presence of an air gap, and also check for jamming of the moving parts and cracks on the short-circuited turns located on the core.

When disassembling and subsequent reassembling a magnetic starter, the relative position of the armature and core that was before disassembly should be maintained, since their worn-in surfaces help eliminate humming. When disassembling magnetic starters, it is necessary to wipe dust from the internal and external surfaces of the plastic parts of the starter with a clean and dry rag.

An electric contactor (magnetic starter) is a switching device, essentially a large relay. Traditionally, a contactor is used to switch the current that powers electric motors or other high-power loads. Often, powerful electrical contactors for electric motors and other equipment are supplemented with overload protection and other criteria. For this purpose, the design of the device uses sensitive bimetallic relays and blocking groups.

PUBLICATION CONTENT:

Design of electrical classic contactors

Classic electrical contactors - also known as magnetic starters - usually have groups of contacts - main and auxiliary.

Contact groups (most often) are in a normally open state. Only if the supply voltage is supplied to the induction coil of the device, the contact groups of the device change their state.

The top three terminals of the main group are used to connect the input three-phase alternating current, usually with a voltage of at least 380 volts. This contact group is equipped with reinforced screw terminals marked “L1”, “L2”, “L3”.

Purpose of the terminals: 1 - line voltage supply; 2, 11 — output under load; 3, 5 — coil power supply; 4, 6 - auxiliary; 7 - sensitivity; 8, 9 — manual shutdown and reset buttons; 10 - auxiliary group

The second main group of terminals, assigned to power the load (or another), is located at the bottom of the device structure and also has screw terminals marked “T1”, “T2”, “T3”.

Each device is traditionally marked with an alphanumeric combination of symbols. The marking is located on the body of the device and carries basic information about the device. For example:

A – 26 – 30 – 10

Here the symbol “A” denotes the series of the device. Next, the number “26” marks the rated current (26A) for the load in the form of an asynchronous electric motor.

The number “30” indicates the number of normally open and normally closed power contacts (3 and 0, respectively). The number “10” indicates the number of auxiliary “NO” and “NC” contacts (1 and 0).

Purpose of auxiliary switching

Auxiliary contacts are often used as part of a relay logic circuit or used as part of some other part of a load control circuit. Typical switching voltage here is 220V AC.

Connection diagram (classic): 1 - magnetic starter; 2 - current protective relay; 3 - electric motor; 4 — “STOP” button; 5 — “START” button; 6 — alarm reset button

Auxiliary contact groups may have different configurations, depending on the device model and manufacturer. The contact state can be either normally closed or normally open. Usually there is a combination of conditions.

The auxiliary interface terminal set is usually designed for a current rating significantly lower than that of the main contacts.

However, the auxiliary group mechanism operates in conjunction with the main switching mechanism of the electrical contactor.

Typically, auxiliary terminals are marked with a digital code. For example, “13” and “14”, “82” and “83”, etc. To some extent, the power terminals of the inductive coil of the electromagnetic system of the device also belong to this category.

The coil power terminals are traditionally marked “A1” and “A2”. The control voltage of the electromagnetic mechanism is supplied to these terminals, usually according to the classical scheme (see above).

Additional protection module

Often the design of the electrical contactor is supplemented. There are designs of electrical contactors where the thermal relay is an integral part.

True, modern versions of electrical contactors provide, rather, modular expansion.

The protective module, often used in conjunction with a magnetic starter, can have different configurations. This is what one of the classic options looks like for a relatively low power load

The most common are contactor relay modules of classes 5, 10, 20, 30. Accordingly, the values: 5, 10, 20, 30 indicate the response time (5, 10, 20, 30 seconds). Class 5 is typically used on motor contactors requiring instantaneous shutdown.

Electrical contactors for special purposes

Electrical circuits at high currents (up to 5000A) are controlled using high-power contactors. Also, special-design devices are used to control asynchronous motors with a wound rotor.

Special version: 1 - upper power connector; 2 - two main connectors with an arc extinguishing chamber; 3 — device frame; 4 - load terminal; 5 - auxiliary terminals; 6 — frame for the periphery; 7 — coil power supply; 8 - electromagnet

The rated switching power parameter for devices of this type reaches a value of 1500 kW. The operating current can be 1520A at a supply voltage of 440 volts.

Electrical contactors of the R series for controlling DC or AC circuits are used where:

• electrical energy distribution,
• induction furnace control,
• switching of alternative energy systems,