How to engage the relay and the reason why the relay is repeatedly engaged

1. The two contacts are disconnected when the dynamic (normally open) (H-type) coil is not energized, and the two contacts are closed after the power is on. It is represented by the pinyin prefix "h" of the ligature.

2. The two contacts are closed when the dynamic breaking type (normally closed) (D type) coil is not energized, and the two contacts are disconnected after being energized. It is represented by the pinyin prefix "d" of hyphenation.

3. Conversion type (Z type) This is the contact group type. This contact group has a total of three contacts, i.e. a moving contact in the middle and a static contact at the top and bottom. When the coil is not energized, the moving contact and one of the static contacts are disconnected and the other is closed.

After the coil is energized, the moving contact will move, so that the original disconnected will be closed, and the original closed will be disconnected, so as to achieve the purpose of conversion. Such a set of contacts is called a conversion contact. It is represented by the pinyin prefix "z" of the word "turn".

Relays are generally composed of iron cores, coils, armatures, contact reeds, etc. After energizing, a certain voltage is applied at both ends of the coil, and a certain current will flow in the coil, resulting in an electromagnetic effect.

The armature will be in the electromagnetic force.

The attraction of the iron core is overcome by the tensile force of the return spring.

When the coil is de-energized, the electromagnetic attraction also disappears, and the armature reacts to the spring.

Return to the original position and release the moving contact from 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. For the "normally open, normally closed" contacts of relays, they can be distinguished as follows: the static contacts that are in the open state when the relay coil is not energized are called "normally open contacts"; Static contacts that are turned on are called "normally closed contacts".

There are many types of relays, such as electromagnetic relays are composed of iron cores, coils, armatures, contact reeds, etc., when a certain voltage is applied to both ends of the coil after the iron core is energized, a certain current will flow in the circle, resulting in an electromagnetic effect, and the armature will overcome the pull of the return spring to attract the iron core under the attraction of electromagnetic force.

<> relay has requirements for the pick-up voltage, only when a certain voltage is reached, the magnetic force generated by the coil can also attract the contact, and realize the on-off and conversion of the relay.

The relay has a coil and a contact, and the contact has a normally open contact (the coil is disconnected when the coil is not energized, and it is closed after being energized), and the normally closed contact (closed when the power is lost, and the electricity is disconnected).

First of all, you can judge which two contacts of the coil of the relay are, you can use the external meter DC file to measure, generally the DC relay is much larger than the DC resistance of the AC relay.

You only have one pair of contacts on 4 feet, and the other two are contacts after the coil is judged.

Power on the relay coil and the relay will be engaged, and the relay is marked with A1 and A2.

The relay coil is turned on and the working voltage is required.

How does the normally closed become normally open after the relay is engaged?

There are three possibilities for the relay not to engage: 1Control circuit open circuit 2The relay coil burned out 3It is also possible that there is a mechanical cause, for example, there is a foreign object in the place of engagement, which causes the seizure.

The reasons for the repeated attachment of the relay are as follows: First, if the attachment and release are not regular and not the control requirements in principle, it is generally the poor contact phenomenon of the relay coil circuit, such as the virtual connection of the connecting wire, the damage of the contact of related devices and the failure of the relay coil. Second, if the suction and release are regular, excluding the principle control requirements and AC relay, such as 100 times a minute, the short circuit ring on the small armature inside the relay is broken.

The reason why the relay is repeatedly engaged.

First, if the suction and release are not regular and not the control requirements in principle, it is generally the poor contact phenomenon of the relay coil circuit, such as the virtual connection of the connecting wire, the damage of the contact of related devices and the failure of the relay coil. Second, if the suction and release are regular, excluding the principle control requirements and AC relay, such as 100 times a minute, the short circuit ring on the small armature inside the relay is broken.

1. Normal frequent on/off: When the load is required to be frequently energized and disconnected, the control circuit of the relay will control its frequent engagement and disconnection. For example, when the circuit controls the relay, the relay will be constantly closed and disconnected.

Second, the relay is frequently turned on and off due to faults. After the relay is engaged, in order to ensure the reliability of its engagement (it will not be disconnected due to external shocks), there is an important measurement parameter, which is the a-pressure of the relay. The a-pressure of the relay must be greater than the specified minimum value to ensure that it engages reliably.

Different kinds of relays, its A pressure value is different. If the A pressure value of the relay is too small, the suction will be unstable, and if there is an external force impact of the gap, it will cause the relay to be continuously turned on and off. The main reason for this is that there are foreign objects on the surface of the magnet or severe wear and tear.

3. The working principle of the relay: The relay is an electrical component that generates magnetic energy from electrical energy and then converts it into mechanical energy output. It consists of a coil, core, armature, reaction spring, reed, and contacts.

When the coil is energized, the core generates a magnetic force that overcomes the ** spring to attract the armature and drive the reed and contact to close. The main technical parameters of the relay: pick-up voltage (generally 75 -50 of the rated voltage) release voltage (generally 30 -10 of the rated voltage), tracking, A pressure, B pressure, contact clearance, power, contact resistance between contacts, insulation voltage.

I think it should be caused by the relay's power supply voltage being too low.

There are several reasons why relays are repeatedly engaged:1The supply voltage is unstable:

If the power supply voltage is unstable, it may cause the relay to engage repeatedly. In this case, it can be solved by using a stabilized power supply or voltage stabilizer. 2.

Failure of the relay itself: If there is a fault in the relay itself, such as poor contact, short circuit of the coil, etc., it will also cause the relay to engage repeatedly. In this case, the relay needs to be replaced or repaired.

3.Control circuit failure: If there is a fault in the control circuit, such as poor contact, short circuit of the line, etc., it will also cause the relay to engage repeatedly.

In this case, the control circuit needs to be inspected and repaired. 4.Load Circuit Fault:

If there is a fault in the load circuit, such as a short circuit, overload, etc., it will also cause the relay to engage repeatedly. In this case, the load circuit needs to be inspected and repaired. 5.

Environmental interference: If there is interference in the environment in which the relay is located, such as electromagnetic interference, electrostatic interference, etc., it will also cause the relay to engage repeatedly. In this case, it is necessary to take corresponding shielding measures to solve the problem.

The K1 relay is disconnected when it is energized, and the KA is self-locked and engaged after being activated by K1. Because K1 is used at the closed point of K2, it is on before power-on, and when it is powered on, the auxiliary point of K1 connects K2 to K2. K1 only completed the startup task of K2, and K2 was able to engage.

This diagram is ideally possible, but not practically.

It is difficult to use relays alone to do your requirements, and other methods can use time relays or resistor-capacitance circuits.

Because your K2 normally closed contact is connected to the K2 coil, when the power is turned on, the K1 relay acts immediately, and the K1 normally open becomes normally closed, so that the K2 coil is energized, and the K2 contact is instantly energized to form a self-locking force on the K2 coil, and the K2 relay remains in a normally energized state.

If you pop off as soon as the relay is engaged, remove the K2 contact, and when the power is on, the relay will be switched to K1 and K2 respectively (but the result is that the relay is not sufficiently engaged, which will cause the relay to be damaged).

From the point of view of this circuit, there is a defect, that is, when K1 is engaged to K2, there will be a situation where K1 disconnects too early and the K2 coil is not enough, and the result may be that only K1 is frequently engaged, and K2 cannot achieve self-locking. If this circuit 100% meets the requirements of K2 pick-up, it is best to add a power-off delay relay to ensure the pick-up time of K2 coil.

Circuit self-protection should be carried out with normally open contacts.

I connect it in parallel with the normally open contact of K1, K2 in this button.

When energized, the K1 coil is energized through the K2 normally closed point, and then the K1 normally open and close. K2 is closed by K1 normally open and energized, and then relies on its own normally open (the following K2 has been closed) to lock itself.

Since K2 is electrified. When the normally closed point of k2 is opened, k1 is also disconnected.

But there may be a time lag in this circuit.

Magnetic latching relays or self-latching relays can be used.

Hello, dear, I've kept you waiting, and now I'll answer for you. The reason for the repeated engagement of the relay is as follows: the rubber ring is aging.

It may be that the rubber ring is used for a long time and is often in a high-temperature environment, resulting in aging and deformation, which leads to problems with the thermal insulation performance of the rice cooker, so the smart rice cooker relay does not stop absorbing and harmonizing. Temperature-sensing soft magnetic failure. If the rice cooker has been used for too long, there will be a situation of temperature sensing soft magnetic failure, and when the rice cooker's chaotic core temperature sensing soft magnetic failure, the rice cooker will also have the situation that the relay keeps sucking.

The pressure switch is in the wrong position. When the pressure switch of the rice cooker is not properly positioned, the rice cooker will be placed in a pressure position that is easier to move after being energized, so that the relay will not stop sucking and commingling.