Please explain the working principle of the shunt trip and the over undervoltage tripper

The shunt tripper is an accessory for manipulating the opening over long distances. The circuit breaker can be reliably disconnected when the supply voltage is equal to either between 70% and 110% of the rated control supply voltage. The shunt tripper is a short-time working system, and the coil energizing time generally cannot exceed 1s, otherwise the coil will be burned out.

In order to prevent the coil from burning out, the molded case circuit breaker is connected in series with a micro switch in the shunt tripper, when the shunt tripper is engaged through the armature, the micro switch is converted from a closed state to a disconnected state, because the control line of the power supply of the shunt tripper is cut off, even if the button is artificially pressed, the shunt coil is never energized to avoid the occurrence of coil burning. When the circuit breaker is snapped back on, the micro switch returns to the closed position. However, the universal DW45 product is shipped by the user in series with a set of normally open contacts in front of the shunt trip coil when in use.

Undervoltage relay or tripper refers to a relay or tripper that makes the mechanical switch electrical disconnected or closed with or without delay when the terminal voltage of the relay or tripper drops to a predetermined value. When the external voltage drops, or even slowly drops to the range of 70% to 35% of the rated voltage, the undervoltage relay and tripper combined with the switching appliance should act to disconnect the electrical appliance.

The use of the two is different, the loss of voltage trip is used for under-voltage and loss of voltage protection actuator, and the shunt trip is generally used for over-current, circuit break, phase failure and other protection actuators; The working mode of the two is different, the coil of the loss of voltage tripper acts when the power is lost, and the coil of the shunt tripper acts when the power is lost.

The loss-of-voltage tripper is connected in parallel on the power supply side of the circuit breaker, which can play the role of under-voltage and zero-voltage protection. When the power supply voltage is normal, the operating handle is triggered, the normally open auxiliary contact of the circuit breaker is closed, the electricity of the electromagnet and the armature are attracted by the electromagnet, and the free trip mechanism can lock the main contact in the closing position, and the circuit breaker is put into operation.

When the power supply side is out of power or the power supply voltage is too low, the electromagnetic force generated by the electromagnet is not enough to overcome the tension of the reaction force spring, and the armature is pulled upward, and the free trip mechanism is pushed through the transmission mechanism to make the circuit breaker trip, which plays the role of undervoltage and zero voltage protection.

When the power supply voltage is 75% to 105% of the rated voltage, the loss of voltage tripper ensures the engagement, so that the circuit breaker closes smoothly; When the power supply voltage is lower than 40% of the rated voltage, the loss of voltage tripper ensures that the circuit breaker is disconnected and disconnected. Generally, the normally closed button connected in series in the electromagnetic coil circuit of the loss of voltage tripper can also be used for opening operation.

Basic features. The traditional circuit breaker protection function is achieved by the action of the mechanical system in the tripper, and its effect is not ideal. In order to prevent the failure of the electrical equipment and the damage to the electrical equipment in the event of an abnormality in the power supply network, a more reliable and protective circuit breaker has been gradually developed on the basis of the traditional circuit breaker.

With the development of microelectronics technology and the emergence of integrated circuits, the volume of ordinary electronic circuits has been greatly reduced, so that multi-functional trippers based on application-specific integrated circuits have appeared, thus promoting the development of multi-functional circuit breakers.

At the same time, the development of microcomputer technology also provides conditions for the intellectualization of low-voltage electrical appliances. The intelligent trip device is the core component of the intelligent circuit breaker, which can not only provide various protection functions of ordinary circuit breakers, but also display various parameters in the circuit in real time, such as current, voltage, power, power factor, etc., as well as communication with the PC and other functions.

The loss of voltage tripper is composed of a loss of voltage coil and a trip mechanism, when the loss of voltage coil is not charged, the circuit breaker can not be closed, the main function is that when the circuit breaker incoming power supply is powered off, the circuit breaker is automatically disconnected, and the circuit breaker is also in a disconnected state when the incoming power supply is restored, and it must be manually operated to close.

The under-voltage tripper generally refers to the action when the coil voltage is less than the rated voltage, so that the circuit breaker trips, and the general action value is 40% 70%, depending on the individual situation.

Loss-of-voltage tripper refers to the action of the coil when there is no voltage, that is, when the power is off.

The shunt tripper is installed on the decoupling mechanism of the circuit breaker (frame air circuit breaker or molded case circuit breaker), and when the shunt tripper passes the current, it will act to open the detaching mechanism of the circuit breaker and trip the circuit breaker.

The shunt tripper is a component of the circuit breaker, and its function is to match the circuit breaker to achieve the design function of the circuit breaker.

The main function is to disconnect the main contact of the circuit breaker to achieve the purpose of circuit breaker excitation.

Like the loss-of-pressure shunt trip in a "frame air circuit breaker". In the leakage air circuit breaker of the molded case, when the leakage current reaches the setting value, it disconnects the main contact by means of a shunt tripper.

The shunt tripper is an electromagnetic tripper, which can make the coil live according to the operator's order or the action signal sent by the relay protection device, and the armature action will trip the circuit breaker and break the circuit. The shunt trip is powered by an operating power supply, which can be either a DC power supply or an AC power supply.

You can remotely use the 24V control sub-trip device to trip the circuit breaker, usually when the fire and non-fire power supply are shared, the non-fire load needs to be installed with the sub-force tripping device, and in the event of a fire accident, the non-fire load is cut off by the fire control room to ensure the fire power consumption.

1. The low-voltage circuit breaker shunt tripper, as the name suggests, is used to break the switch, when the shunt tripping coil is passed through the rated voltage, the circuit breaker is opened.

2. The under-voltage tripper is used for under-voltage protection, when the line power supply voltage is lower than the voltage of the under-voltage tripper, the circuit breaker will automatically open and re-close when the call comes again.

3. Electromagnetic tripper is a kind of tripper, which only provides magnetic protection, that is, short-circuit protection.

4. The function of the thermal tripper is mainly used to protect the overload of the circuit breaker, when the circuit breaker is overloaded, the thermal trip action will disconnect the circuit breaker.

The above kinds of trippers, an ordinary universal circuit breaker have these protection functions.