How do relays interlock work? How do relays interlock with each other? Who knows

Other switches are controlled by means of an electromagnet.

The working principle and characteristics of relays.

Relay is an electronic control device, it has a control system (also known as an input loop) and a controlled system (also known as an output loop), usually used in automatic control circuits, it is actually a kind of "automatic switch" to control a larger current with a smaller current. Therefore, it plays the role of automatic adjustment, safety protection, and conversion circuit in the circuit.

Interlock principle and characteristics of electromagnetic relays.

Interlocking: The role of two relays through their own normally closed auxiliary contacts that prevent each other from being energized at the same time is called interlocking. Electromagnetic relays are generally composed of iron cores, coils, armatures, contact reeds, etc.

As long as a certain voltage is added to both ends of the first circle, a certain current will flow through the coil, resulting in an electromagnetic effect, and the armature will overcome the tensile force of the return spring under the action of electromagnetic force attraction to attract the core, thereby driving the dynamic contact of the armature to engage with the static contact (normally open contact). When the coil is de-energized, the electromagnetic suction force disappears, and the armature returns to its original position under the reaction force of the spring, so that the moving contact engages with the original static contact (normally closed contact). In this way, it is engaged and released, so as to achieve the purpose of conduction and cutting in the circuit.

And then realize interlocking.

Relays use their own self-locking principle to connect to another relay in series to achieve mutual locking.

Relay self-locking meaning: The phenomenon that the AC contactor always keeps the coil in an energized state through its own normally open auxiliary contact is called self-locking.

This normally open auxiliary contact is called a self-locking contact. After the contactor coil is energized, its own normally open auxiliary contact is used to keep the loop connected in the acre state, and the general object is the control of its own circuit. If the normally open auxiliary contact is connected in parallel with the start button, so that when the start button is pressed, the contactor acts, the auxiliary contact is closed, and the state is maintained, and then the start button is released, and the contactor will not be disconnected due to power loss.

After the contactor coil is energized, its own normally open auxiliary contact is used to keep the loop on, and the general object is to control its own circuit. If the normally open auxiliary contact is connected in parallel with the start button, so that when the start button is pressed, the contactor acts, the auxiliary contact is closed, and the state is maintained.

Generally speaking, in addition to the parallel connection of the start button and the auxiliary contact, a button should be connected in series to play a stopping role. In the jog switch, the normally open contact is selected for starting, and the normally closed contact is selected for stopping.

1. Electrical mutual locking:

The interlock in electrical control is mainly set to ensure the safe operation of electrical appliances. It is mainly interlocked by two electrical devices controlling each other.

2. Essence of electrical interlocking:

The normally closed shock of the two relays is connected to the coil control loop of the other relay. Therefore, one relay is energized and it is not possible to form a closed loop on the other relay coil. But this can also be done by mechanical connections.

3. For example: connect the normally open auxiliary contact in parallel with the start button, so that when the start button is pressed, the contactor acts, the auxiliary contact is closed, and the state is maintained, and then the start button is released, and the contactor will not be disconnected due to power loss.

Connect the switch in series on the main contact of the relay (relay coil). At the same time, a free secondary contact (normally open contact) of the relay is connected in parallel with the switch (and connected to the main contact). In this way, the switch is pressed, the secondary contacts (normally open contacts) are engaged, and the circuit is energized; When the switch is released, the coil in turn keeps the secondary contact engaged as the secondary contact is engaged and the pin supplies power to the coil of the relay's main contact.

Then the line is led out from the output of the electric power station, and the circuit can be continuously energized.

Introduction to Self-Locking Circuits:

A self-locking circuit is a type of circuit that, once a switch is pressed, automatically remains continuously energized until another switch is pressed to break the circuit. In the usual circuit, the switch is pressed, and the circuit is energized; Release the switch and the circuit is disconnected.

Latching refers to "self-locking", which is to automatically lock the state of the relay after it is energized, keep the loop on, and even if the control current is disconnected at this time, its state will not be changed. That is, when the power is turned on, the control current is disconnected and it continues to remain on unless the unlock button is pressed.

Latching relay: It can be divided into 1-coil latching type and 2-coil latching type.

1) 1 coil latching relay: coil energized, contact action; The coil is powered off, the contact is still in the previous state, and the contact is reset only when a reverse voltage is added to the coil.

2) 2 coil lock relay: energize the set coil and the contact action; When the coil is powered off, the contact remains in the previous state, and the contact is reset only when the reset coil is energized.

Summary. If KM1 and KM2 operate at the same time, the main circuit will be seriously short-circuited, resulting in an accident. Therefore, the normally closed contacts of KM1 are connected in series in the KM2 coil circuit, and the normally closed contacts of KM2 are connected in series in the KM1 coil circuit.

Once KM1 is energized and rotated, KM2 cannot be energized, which objectively prevents short-circuit accidents. The normally closed contact of one contactor is connected to the wire package of the other contactor, so that the interlocking of the two contactors is realized, that is, one contactor is energized, and the other contactor cannot be energized.

If KM1 and KM2 operate at the same time, the main circuit will be seriously short-circuited, resulting in an accident. Therefore, the normally closed contact of KM1 is connected in series in the KM2 coil circuit, and the normally closed contact of KM2 is connected in series in the KM1 coil loop photographer. Once KM1 is energized and rotated, KM2 cannot be electrified, which objectively prevents dry shooting and short-circuit accidents.

The normally closed contact of one contactor is connected to the wire package of the other contactor, so that the interlocking of the two contactors is realized, that is, one contactor is energized, and the other is unable to be energized.

Excuse me, but please go into more detail?

If a self-protection circuit is connected, the control requirements can be satisfied. The wiring is as follows. Taking the coil voltage of 220V as an example, the normally closed contact of the stop button is connected to the power supply (L), the output of the stop button is connected to the start button, and a self-locking wire is introduced to the normally open (NO) transmission of the contactor, and the contactor is normally open and the output coil A1 is connected, and the coil A2 is connected to the N line.

Start the button output coil A1. If you need to add an indicator light, connect the power indicator directly to the power supply in parallel, and the working indicator directly connect to the contactor coil in parallel.