Starter connection diagram for 2 start buttons. Starter connection diagram
A contactor is an electromagnetic device designed to switch, that is, turn on and off, electrical equipment. It is a two-position mechanism that is used for frequent switching. The main elements of its design are:
- Power contact group, which can be two and three-pole, depending on the voltage required for the operation of the actuator.
- Arc chutes, which are aimed at reducing the arc that occurs when breaking electric current;
- electromagnetic drive. It is designed to move the moving part of the power contact. Depending on the design, it can be designed for different voltages of both direct and alternating current. It is made from a U-shaped, or W-shaped core;
- Block-contact system, necessary for signaling and controlling the operational circuits of the contactor. Using them, you can connect a sound or light alarm showing the position of the contactor, as well as for the self-pickup circuit.
A distinctive feature of the design of an electromagnet operating with alternating current is the presence short-circuited coil, which prevents the buzz of his iron during operation. If the electromagnet is powered by direct current, then between the disconnected parts of it, there must be a non-metallic gasket that prevents the core from sticking. The contactor differs from a magnetic starter or relay, only by working with a more powerful load, the size of the device itself depends on its size. It is very important to choose the right contactor corresponding to the current that it will switch.
Modern devices of the KMI series have good reliability indicators and are designed for general industrial use. Due to their design, they have an easy mounting method and small dimensions.
Principle of operation
When voltage is applied to the electromagnet coil, the movable part of the apparatus is set in motion under the influence of electromagnetic forces and is attracted to the stationary part. In this case, the power contacts are closed and voltage is applied to the actuator. And also at the same time, the block contacts move, which can be closing or breaking.
How to connect a contactor
When connecting a contactor, you immediately need to decide on the mechanism that it will turn on. It can be a motor, a pump, a fan, heating elements, compressors, etc. Main feature contactor, which distinguishes it from the machine, is the absence of any protection. Therefore, when thinking over the circuits for switching on electrical equipment through a contactor, it is imperative to take into account the current and heating limiting elements. Fuses and circuit breakers are used to limit and disconnect equipment in case of short circuits and loads exceeding the nominal load many times over. Thermal relays are used for prolonged slightly exceeding the rated currents of operating equipment.
In order to correctly connect the contactor to the circuit, you need to clearly understand which of the contacts are power, and which of them are auxiliary, that is, auxiliary contacts. You also need to look at the ratings of the switching coil. There must be indicated the voltage, its type and magnitude, as well as the currents that flow through it for normal operation. During operation, power contacts can burn out, so they must be regularly inspected and cleaned.
How to connect a modular contactor
A modular contactor is a kind of conventional switching devices of the same type, only they are mainly used to turn on and off switchboards remotely. That is, including it, power is supplied to a group of automata, each of which is responsible for its own specific circuit. It is installed on a DIN rail. It can switch both DC and AC circuits.
Contactor connection via button
To connect the contactor through the button, you need to study the attached diagram below. It is designed to start the load, in this case the motor, from the contactor, the coil of which is designed for 220 volts of alternating voltage. Depending on the voltage, it is worth considering its power supply. Therefore, when buying and choosing a contactor, it is worth considering this nuance. Since if the electromagnet is designed for constant pressure, then you need just such a source.
When the start button is pressed, the contactor solenoid coil will receive power and it will turn on. The power contacts will close, thereby energizing the asynchronous motor. The auxiliary contact of the contactor K1, which is connected in parallel with the stop button, will also close. It is called by electricians the self-retaining contact, since it is he who supplies power to the closing coil after the start button is released. When the stop button is pressed, power is turned off from the electromagnet, the power elements of the contactor break the circuit and the engine turns off.
Connecting a contactor with a thermal relay
The thermal relay is designed to prevent prolonged minor current overloads during the operation of electrical equipment, because overheating adversely affects the state of the insulation. Frequent excesses of temperature and currents will lead to its destruction, and hence to a short circuit, and failure of an expensive actuator.
With an increase in current in the stator circuit of the electric motor, the elements of the KK thermal relay will heat up. When the set temperature, which can be adjusted, is reached, the thermal relay will work and its contacts will break the circuit of the electromagnet coil of the KM contactor.
For safety reasons, it must be remembered that work in the contactor circuit must be carried out when it is completely de-energized. In this case, the automatic power supply must be blocked with a key or a prohibition poster from unauthorized or erroneous switching on. And also you can not turn on this device with the arc chutes removed, this will lead to a short circuit.
Video about connecting a contactor
A magnetic starter is an electrical device that is designed to start at a distance, help in work, turn off and save the electric motor. It is easy to assemble a connection diagram for a magnetic starter through a push-button post. The operation of the magnetic field is based on the effect of the appearance of a magnetic field when the current penetrates through the induction load, that is, through the coil.
What is MP used for?
Often, starters are used to mechanically turn on heaters, lighting lines, etc. They are also used for engine operation. MP connection schemes differ mainly depending on which coil is in it. Turning on the starter yourself is not difficult, but you can make it easier and purchase the starter already assembled, best of all, with a plastic case.
In it, the structure is already assembled and the control buttons on the lid are connected. It is only necessary to connect the electrical cables at the top and the outlet wire to the load.
Coil MP
The coil is the main part of the MP, it creates an electromagnetic field when electricity passes through it, and involves an armature, 3 or 5 pairs of mobile contacts. The type of coil depends on the voltage in the installation. They can operate on 220 volts or are calculated on 380 volts. The coil, with a calculated 220 volts, is connected by terminals between ground and phase. 380 volts are connected between phases.
The voltage value is usually written on its output next to the bolt that clamps the wire. If a 220 volt coil is turned on like 380 volts, it will explode.
Assembly preparation
Before directly assembling the circuit for connection, you need:
Types of starter designs
For the reverse design of the MP, the first, third and fifth terminals are connected with the same numbers of the neighboring device. And the outgoing wires are connected crosswise: the second with the sixth, the fourth with the fourth, the sixth with the second. The wire that feeds the electric motor is connected to the second, fourth and sixth terminals of any starter.
The cross connection scheme prohibits the simultaneous operation of two devices, because this will lead to a short circuit.
Because of this, it is necessary that the conductor of the block circuit of both starters pass first through the closed contactor of the other, then through the open contact of its own. Then, when the first device is turned on, the second device will be turned off and vice versa.
Some MP designs involve only 5 pairs of contactors, which are closed. Then the wire of the block chain of the 1st MP is connected to closed contacts"Start" another. This design operates in the start-stop order.
3 wires are connected to the second terminal of the "Stop" button: 2 blocks and one that feeds the "Start", these wires are connected in parallel with respect to each other. With this design, "Stop" turns off any device and stops the operation of the electric motor.
All work on the installation and repair of MP structures is done after the voltage is removed, even if the control switches the neutral.
MP connection diagram
A popular scheme for connecting a magnetic starter through a push-button post.
The main circuit has two parts:
- Three pairs of power contacts direct electrical power to electrical equipment.
- A graphical representation of the control, which is made up of a coil, buttons and additional contactors that take part in the operation of the coil or do not allow erroneous switching on.
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The most common is the single device wiring diagram. She is the easiest to deal with. To connect its main parts, you need to take a three-core cable and a pair of open contactors when the device is turned off.
Scheme with connecting a 220 volt coil
Analyze the design with a voltage of 220 volts. If the voltage is 380 volts, instead of a blue zero, you need to connect a phase of a different kind. In this situation, black or red. In case of blocking the contactor, the fourth pair is taken, which works with 3 power pairs. They are in the upper part, but the side ones are located on the side.
3 phases A, B and C are supplied to pairs of power contactors from the machine. To turn on when you touch the "Start" button, it is necessary that the voltage is 220 V on the core, which will help the movable contactors connect to those that are stationary. The circuit will begin to close, in order to disconnect it, you need to disconnect the coil.
To assemble the control circuit, you need to connect one phase directly to the core, and connect the second phase with a wire to the start contact.
From the 2nd contactor we lay 1 more wire through the contacts to another open contact start button. From it, a blue jumper is made to the closed contactor of the "Stop" button, zero from the electrical supply is connected to the 2nd contactor.
Working Principle
The principle of operation is simple. If you press the "Start" button, its contacts begin to close and a voltage of 220 volts goes to the core - it starts the main and side contacts and an electromagnetic flux occurs. If the button is released, the contactors of the start button open, but the device is still on, since zero is transmitted to the coil through the closed blocking contacts.
In order to turn off the MP, you need to break the zero by opening the contacts of the Stop button. The device will not turn on again, because the zero will be broken. To turn it on again, you will need to press "Start".
How to connect a thermal relay?
You can also draw up a one-line graphical drawing of connecting a three-phase electric motor to a magnetic starter through a relay.
A relay is connected in series between the MP and an asynchronous electric motor, which is selected depending on the specific type of motor. This device protects the motor from breakdowns and emergency mode (for example, when one of the three phases disappears).
The relay is connected to the output from the MP to the electric motor, electricity passes in it in a sequential manner through the heating of the relay to the electric motor. On top of the relay are auxiliary contactors, which are combined with the coil.
Relay operation
Thermal relay heaters are designed for the maximum value of the current that passes through them. When the current rises to unsafe limits for the motor, the heaters turn off the MP.
Installation of starters inside the electrical panel
MP design allows installation in the middle of the electrical panel. But there are rules that apply to all devices. To ensure high reliability of operation, it is necessary that the installation is carried out on an almost straight and solid plane. Moreover, it is located vertically on the wall of the electrical panel. If there is a thermal relay in the design, then it is necessary that the temperature difference between the MP and the electric motor be as small as possible.
In what places it is impossible to do the installation of the MP
In order to prevent accidental activation of the starter or to protect it, it is impossible to install the device in places that are susceptible to shocks, shocks, and shaking.
It is also impossible to install the MP in the same room with devices that have a current higher than 150 A. When these devices are turned on and off, a quick blow occurs.
The wires in the wiring diagram also need to be laid correctly. In order for there to be good contact and there was no curvature of the washers of the spring clamps, it is necessary to bend in a round shape.
The design of the device is made after removing the voltage. Cores can work from 220 volts, or from 380. You can also buy a ready-made MP, this will greatly simplify the situation.
For those who were normal about studying a school physics course, it will not be difficult to figure out the connection diagrams for various electrical equipment, including three-phase electric motors. They are connected via contactors or magnetic starters. Foreign classification does not make a difference between these devices, since the starter is the same contactor, but equipped with additional devices for safe work current consumer.
In other words, the starter is a kind of electrical cabinet in miniature, in which, in addition to the contactor, thermal protection is also installed against short circuits. Starters have 8 values from "0" to "7", each of which is designed for electric motors with a certain power range (rated current). Due to the closed design (in the housing), the starters can be installed anywhere. When connecting electric motors through a contactor protective devices are selected separately.
Contact system on the contactor
Regardless of the size and manufacturer of electrical equipment, any three-phase contactor has a standard contact and connection diagram. For ease of installation, all contacts are marked indicating their purpose. The marking is applied to the body of the device and looks like this:
- A1 (zero) and A2 (phase) - contacts for controlling the on and off of the contactor;
- Odd numbers 1, 3, 5 and markings L1, L2, L3 indicate the input points of the three-phase power;
- The even numbers 2, 4, 6 and the markings T1, T2, T3 indicate the connection points of the wires going to the current consumer;
- 13NO and 14NO are a pair of auxiliary contacts to provide the self-retaining function.
Contact A2 is duplicated in the upper and lower parts of the device for easy switching. For the same purpose, the upper and lower (odd and even) group of power contacts can also be used for input or output of power. When installing the contactor, you must be careful, otherwise the circuit will not work.
Phases must not be connected incorrectly. If you mix them up when installing the contactor, you will get reverse rotation of the motor. For this, two ways of marking on the insulation of cable cores are provided - by numbers and by color. The colors 1, 2 and 3 are yellow, green and red. The neutral conductor is white or marked with the number "0". Connecting power contacts is not difficult. The main thing is the correct connection of the control voltage through the push-button post.
Button post connection
Consider 2 schemes for connecting a contactor to a 380 V network: for a coil with a supply voltage of 380 V and 220 V.
The button post has two buttons. "Start" with normally open and "Stop" with normally closed contacts. Power to it (phase) is supplied through contact No. 4 of the Stop button. Between terminals No. 3 "Stop" and No. 2 "Start" we install a jumper, thereby extending the "phase" line. Terminal A1 (phase) of the contactor is connected to contact No. 1 "Start". The neutral core of the control wire is connected to terminal A2. A jumper is installed between the double contact A1 and terminal 14NO. Terminal 13NO is connected to contact No. 2 "Start".
If the control circuit needs to be powered from one phase (phase-zero), with a starter coil rating of 220 V, the connection diagram will look like this.
When the "Start" button is pressed, the power contacts are activated and voltage is applied to the auxiliary contact, which ensures the working (closed) position of the power contacts after the button is released. By pressing the "Stop" button, the circuit on the auxiliary contact is broken, and the power contacts move to the normally open position. More detailed descriptions connection of contactors with illustrations and videos can be found on the Internet. Having done this work several times, in the future you will do it automatically.
Magnetic starters - electromechanical devices, designed for simultaneous connection of the consumer of electrical energy to three supply phases. Its action is based on the effect of the appearance of a magnetic field when an electric current passes through an inductive load (draw-in coil). They are used, as a rule, to control three-phase electric motors, as well as, for example, in emergency transfer systems.
The main difference in the connection and control schemes of the magnetic starter is what type of retractable coil it uses.
The retracting coil of a magnetic starter is its “heart”, which initiates a magnetic field when an electric current passes through it and draws an armature with three (sometimes five) pairs of moving contacts. The type of coil depends on the magnitude of the response voltage. They are:
- Operated by voltage 220 V.
- Designed for voltage 380 V.
Coil terminals for 220 V are connected between phase and neutral (ground). Three hundred and eighty volts - between phases. The operating voltage of a coil is usually written on its dielectric terminal next to the wire clamp bolt.
Two hundred and twenty volt coils explode spectacularly when turned on between phases.
How to connect a magnetic starter
When the armature of the magnetic starter is drawn into the hole of the electromagnetic coil, two actions occur:
- Pairs of movable contacts at the armature are closed with fixed contacts on the starter housing, due to which the supply voltage is switched and the consumer (motor) is connected.
- Groups of control contacts are triggered (they are closing and opening), to which the "Start" and "Stop" buttons are connected, as well as the controlled terminal of the electromagnetic coil.
When installing a magnetic starter, one phase from its supply terminal (from the side of the power line) is supplied to any terminal of the retracting coil. This connection is permanent. The second terminal of the electromagnetic coil is connected to the control circuit.
Three-phase motors are often used at home. For correct connection such a device, you need to know its characteristics, advantages and disadvantages, as well as.
For installation of high power devices in single-phase network just look at the following.
If the coil is designed to operate from 220 V, then the control circuit switches the neutral. If the operating voltage of the electromagnetic coil is 380 V, then the current flows in the control circuit, "taken" from the other supply terminal of the starter.
The type of control circuit depends on whether you are going to reverse the motor or not.
Control circuit without motor reversal
If it is not required to change the direction of rotation of the motor, then two non-latching spring-loaded buttons are used in the control circuit: one in the normal position is open - “Start”, the other is closed - “Stop”. As a rule, they are made in a single dielectric case, while one of them is red. 
Such buttons usually have two pairs of contact groups - one normally open, the other closed. Their type is determined during installation work visually or with the help of a test device (tester) switched on in the audible alarm mode.
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Motion sensors are used to organize home lighting. You can read how to choose them, and the features of its connection scheme are disclosed.
The control circuit wire is connected to the first terminal of the closed contacts of the Stop button. Two wires are connected to the second terminal of this button: one goes to any of the nearest open contacts of the Start button, the second one is connected to the control contact on the magnetic starter, which is open when the coil is off. This open contact is connected by a short wire to the controlled terminal of the coil.
The second wire from the "Start" button is connected directly to the retractor coil terminal. Thus, two wires must be connected to the “retracting” controlled terminal - “straight” and “blocking”.
The principle of operation of a magnetic starter in such a circuit is as follows: when the “Start” button is closed, the terminal of the retracting coil is connected to phase or neutral, which causes the magnetic starter to operate. In this case, pairs of movable contacts at the armature are closed with fixed ones and voltage is applied to the engine.At the same time, the control contact closes and, thanks to the closed “Stop” button, the control action on the retracting coil is fixed. When the "Start" button is released, the magnetic starter remains closed. Opening the contacts of the "Stop" button causes the electromagnetic coil to be disconnected from the phase or neutral and the electric motor is turned off.
Connection diagram of a reversing magnetic starter
Before connecting a reversing magnetic starter, it is necessary to understand the constituent elements of the proposed circuit.
To reverse the motor, two magnetic starters and three control buttons are required. Magnetic starters are installed next to each other. For greater clarity, we conditionally mark their supply terminals with the numbers 1–3–5, and those to which the motor is connected as 2–4–6. 
For a reverse control circuit, the starters are connected as follows: terminals 1, 3 and 5 with the corresponding numbers of the neighboring starter. And the “output” contacts are crossed: 2 with 6, 4 with 4, 6 with 2. The wire supplying the electric motor is connected to three terminals 2, 4, 6 of any starter.
With a cross connection, the simultaneous operation of both starters will lead to a short circuit. Therefore, the conductor of the "blocking" circuit of each starter must first pass through the closed control contact of the neighboring one, and then through its open one. Then the inclusion of the second starter will cause the first one to turn off and vice versa.
In some designs of magnetic starters, there are only five pairs of closing contacts. In this case, the blocking circuit wire of one starter is connected to a permanent closed contacts start button of another. As a result, it starts to work in the start-stop mode.Not two, but three wires are connected to the second terminal of the closed "Stop" button: two "blocking" and one supplying "Start" buttons, connected in parallel to each other. With this connection scheme, the "Stop" button turns off any of the switched starters and stops the electric motor.
All installation and repair work in the wiring diagrams for connecting the magnetic starter is carried out with the voltage removed, even if the control circuit switches the neutral.
An example of using a reversing magnetic starter - video connection diagram
For the correct connection of powerful loads, an electromagnetic 220v starter is used. The special design ensures synchronous closing of the contact groups and a break in the power circuits of the same quality. Unlike classic knife switches, remote start and protective functions can be performed using a thermal relay.
Application area
The electromagnetic starter 380v (220v) is used to connect:
- machine motor;
- heating element of the melting furnace;
- lighting systems (heat supply);
- duct fan;
- conveyor belt drive.
Many examples could be given. However, this list is enough to understand the intended purpose - supplying power to a powerful load. It implies work with sufficiently strong currents at standard mains voltages, 220V or 380V, respectively.
The principle of operation of the electromagnetic starter 220v
The main function of the device is the synchronous movement of power contacts for closing / breaking electrical circuit. This movement is provided by an induction coil. When voltage is applied to the winding, an electromagnetic field is formed, which draws in the core with a fixed contact group.
The design of the magnetic starter
The picture below shows the components of a typical starter. The stationary lower part, when the coil is connected to the power supply, forms an electromagnetic field that attracts the moving element. The contacts connected to the armature close the working circuit. If the winding is de-energized, the spring will return the system to its original state.
Sectors with symbols
Explanatory inscriptions on the body are divided into three groups:
- general information and scope (AC1-4);
- information on permissible currents in load circuits (conversion to kW or reverse is performed taking into account the mains voltage);
- graphic designation of contact groups (dashed line indicates synchronous switching).
Each area can be explored in detail. To get acquainted with the classification by category of destination, they are guided by the standards of GOST R 50030.4.1.-2002. The designation AC1 indicates the possibility of connecting the starter to heating elements, incandescent lamps and other loads with weakly expressed reactive characteristics. If you need to ensure the start of a powerful engine, choose a model of category AC3.
This part is mounted on a 220v electromagnetic starter to expand the basic functions:
- activation of the reverse mode of the engine;
- additional load management;
- turning on the indicator light.
Note. A typical attachment mechanism contains two pairs of contacts. Rigid fixation of the block in a certain place is provided by a special shape of the protrusions of the docking platform. When choosing a suitable model, one should take into account the compliance with the starter, as well as the normally closed / open state of the contact group.
Contact groups of starters
According to current standards, the input and output terminals are marked with Latin letters L and T, respectively. In fact, the sequence does not matter. You can connect paired contacts to the power source and load in any combination. This is the main difference from a relay, where a permanent connection is made to one of the power supply circuits.
A separate contact group (13H0, 14H0) is designed for the operation of the independent "pickup" circuit. In this mode, the push-button start is activated by pressing once without holding.
stop button
The control circuit of any starter is organized using two buttons without fixing the on position. "Stop" is marked in red for increased safety. In an emergency, this bright identification speeds up the disconnection of the power supply.
In the initial position of the Stop button, the circuit is closed. When pressed, the induction coil is disconnected from the current source. The electromagnetic field disappears. The spring returns the armature to its original state with the simultaneous opening of the main contact group. The secondary closure of the circuit in this area does not matter, since the general break is provided by the "Start" button.
Note. The compactness of modern starters should be emphasized. Such products are adapted for mounting on a standard din rail.
start button
This control is created in black (green) color. In the initial state, the contacts are open. Pressing activates the formation of a magnetic field and the movement of the main contact group. "Self-pickup" ensures the functionality of the working power circuit after the start button returns to its original position.
Classic switching circuit
This option is used to solve typical problems. The standard starter connection scheme implies the performance of certain actions when the control buttons are pressed:
- "Start" - an electromagnet attracts a platform with contact groups, closed circuits supply current to the load;
- "Stop" - holding the moving part of the structure by the electromagnetic field stops, the spring returns the block to its original state, the load power is turned off.
If you use a 380v magnetic starter, you can organize the connection of a powerful engine or a set of several heating elements. It is possible to divide loads into several phases: L1, L2 and L3. In this situation, one should not forget about the uniform distribution of power over individual lines.
In this example, the winding parameters are the same. Therefore, additional calculations of load proportionality are not needed. Control devices are connected to L1 and neutral conductor. The voltage in this circuit is 220V (380V between the individual phases). For additional protection(not shown in the figure) an automaton is installed at the input, which is selected according to the maximum allowable current.
Note. A fuse can be added to the circuit in front of the button, which will prevent damage to the coil during a large increase in voltage in the power supply.
After briefly pressing the "Start" button, the contact group supplies voltage to the motor windings. The mechanism of "self-pickup" holds the working position. The current flow circuit according to the scheme: L1 - 1 - 2 - self-pickup - 3 - KM - N. To turn off the power unit, press "Stop", which interrupts the power supply to the load.
To connect an electric motor with a reversible operating mode, the magnetic starter connection diagram shown below is used. The added group of controls (“Forward” and “Back” buttons) provides power to the windings through different contact groups. The normal direction of rotation or reverse is activated accordingly.
An additional element, the thermal relay RT1, prevents damage to the motor in the event of a locked rotor or excessive load from the drive mechanism. Heating of the control area opens the power supply circuit of the coils (KM1 or KM2). By analogy with the operation of the "Stop" button, the contact groups are disconnected in the phase lines.
Important! This circuit does not protect against short circuits. The corresponding functions are performed by the automaton (QF).
Types of electromagnetic starters
To eliminate errors, you need to clarify the names of the products of this group. By current standards, the starter is a fully functional device with control buttons in a dust and moisture resistant housing. It is allowed to have in the kit:
- thermal relay;
- light indication;
- prefixes with additional contact groups.
The contactor, by definition in the standards, consists of a drive and a contact group. To control such a product, an external push-button post is used. In some models, there is no protective case, since indoor use is implied. Remote connection contactor can be automated. Additional external components provide signaling of operating modes and emergencies.
The figure shows how to connect the contactor to the remote control. This method is used to control remote stationary power units, moving mechanisms (overhead crane drives). Starters for three-phase electric motors divided into groups to quickly identify the right set of equipment.
Selection of operating parameters
| Group | Permissible motor power (380V), kW | Rated current depending on the version, A | |
|---|---|---|---|
| open | closed | ||
| 0 | 1,5 | 3 | 3 |
| 1 | 4 | 10 | 9 |
| 2 | 10 | 25 | 23 |
| 3 | 17 | 40 | 36 |
| 4 | 30 | 63 | 60 |
| 5 | 55 | 110 | 106 |
| 6 | 75 | 150 | 140 |
The picture shows an example of a model with two Start buttons (indicated by arrows). Such devices are used to control the direction of rotation of the motor rotor. If necessary, one press activates the normal mode or reverse.
Electric starters with thermal relay
These devices prevent damage to the connected equipment in case of violation of the thermal regime. In a typical design, a combined plate of two different metals is used. Passing too much current through this element increases the temperature. Since the materials differ in coefficients of linear expansion, a planned deformation occurs. At a certain level, the control circuit (coil) of the magnetic starter breaks. In some models of the thermal relay, the possibility of adjustment is provided (± 25% of the nominal value). The response time is from 3 to 25 s.
Design versatility
The previous example demonstrates the possibility of using a starter circuit with a start-stop button for various tasks. If necessary, standard products can be upgraded. By adding external components, they provide mode indication and protective functions, interface with automation equipment. The basic design is suitable for connecting inductive and resistive loads, for operation with direct and alternating currents. The contact group does not create significant electrical resistance when closed.
Fixture mounting
Products of this category are fixed on a flat vertical surface at a stable temperature. The switchboard uses a standard din rail for mounting. When choosing a suitable location, excessive vibrations, accidental mechanical damage. If the starter circuit is assembled with a thermal relay, the proximity of heating devices is prevented. When installing cable products in the clamps, the position of the washers is controlled, avoiding distortions. stranded copper wires twist, apply tinning. Before starting operation, check the free movement of moving components of the structure.
ATkeysestarters in three-phase networks
When working with certain power supplies, it is necessary to take into account the voltage for which the inductor is designed. In three-phase power supply networks, 220V control circuits are connected to the phase and neutral conductor. A 380V coil is connected to any two phases.
Service
Some malfunctions of magnetic starters can be recognized by a characteristic humming sound. As a rule, this happens when the connection between the armature and the core is not tight enough. Excessive case heating is also indicative of malfunctions or excessive load current. An increase in temperature provokes a short circuit between the turns of the induction coil, dirt or oxides in contact group. Be sure to check the quality of the clamp of the connected wires.
Degree of protection
According to this parameter, single-phase and three-phase models are divided into three main groups according to the international standard classification IP:
- Open version (IP00) does not provide protection against external influences. Suitable for installation in special cabinets or rooms with controlled temperature and limited humidity.
- Equipment of category IP40 implies the presence of a case with holes. Operation in unheated rooms is allowed, but it is necessary to provide protection against moisture.
- When marked IP54, the product can be installed outdoors. With the help of a canopy, direct sunlight and precipitation are prevented.
Safety
Starters must be checked regularly to maintain safe operation. Basic Rules:
- work with installations under voltage is carried out using special protective equipment;
- disconnected sections indicate, prevent accidental connection of the power source (remove fuses, provide supervision, hang out warning posters);
- check the absence of voltage;
- use grounding.
The information provided will help you select and apply an electromagnetic starter without errors. At the stage of project preparation, it is recommended to clarify the purpose of the scheme and operating conditions. To solve complex problems, a serial product is supplemented with display means and other external functional components.
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