DZ47 Circuit Breaker Accessories (MV overvoltage shunt release, MN undervoltage shunt release, MV + MN overvoltage-undervoltage shunt release, MNS no-voltage shunt release, MX shunt release, MX + OF shunt release + Auxiliary contacts, SD alarm contacts, OF auxiliary contacts) is auxiliary functional components designed for DZ47 series miniature circuit breakers by TAIXI, such as electrical lines or home, building, according to the need to choose different circuit breaker accessories and match with DZ47 series miniature circuit breakers , in order to achieve the circuit breaker undervoltage, overvoltage, overvoltage-undervoltage, no-voltage, lack of auxiliary control, alarm and other protections.

Principle of shunt release

Shunt release is essentially a opening solenoid plus release. Thermal release and electromagnetic release also use this release. when the shunt trip coil in the specified voltage, the circuit breaker will trip and open. Shunt release commonly used in remote automatic power-off control, and now the most used is that the fire control room cut off the non-fire power.
After shunt trip, circuit breaker can not be immediately remote control closing, and can not be directly closed manually, the circuit breaker must buckle again before closing, this is the same as overload and others buckle again after the trip. This is the distinction between shunt tripping and electric operation.
Circuit breaker operating handle has three positions, in addition to the upper and lower positions we know, after the trip, the handle will stay in the middle. The so-called re-button is the handle from the middle position to pull the opening-position to make release hook again, and then it can be closed.
Types of shunt release coil voltage are AC and DC, the voltage size has a variety of voltage levels. It is the most convenient and most simple that DC24V power supply is used as shunt release coil power when cutting off the non-fire. Shunt release coil can be power on for a short time, burn out over time; so in the control loop, it should connect in series with normally closed contacts of circuit breaker, circuit breaker after trip cut off the current of shunt release coil.

Function of shunt release function

Shunt release is used for remote operation of low-voltage circuit breaker opening control. And its electromagnetic coil is connected in parallel to the power supply side of the low-voltage circuit breaker. When needing opening operation, press the normally open button to make the electromagnet of shunt release electric have the electric to absorb armature, through the transmission mechanism to promote the free trip mechanism, so that low-voltage circuit breakers trip.
When a low-voltage circuit breaker is equipped with two or more kinds of release, the low-voltage circuit-breaker is equipped with a double-release. In specific use, the shunt trip focus on control, no-voltage trip focus on protection.

Definition of release

Definition: A device mechanically connected (or integral) to a circuit breaker for releasing the holding mechanism and make the circuit breaker turn off automatically. (GB 10963.1-2005 / IEC 60898-1: 2002)
In general, the traditional bimetal mechanical or electronic electromagnetic release and trip mechanical parts compose the whole, The intelligent release is not including mechanical tripping part, only refers to the control panel (can be understood as "controller" built in circuit breaker )..
Shunt release is equipped with leakage protector, the effect is protection of leakage or the personal electric shock in the circuit by zero sequence current transformer.
The current vector sum of shunt release is not equal to zero, secondary coil of the transformer creates voltage on both sides and amplified by the integrated circuit, when it reaches the set value, it can cut off the power within 0.1s by the leakage release, which protects electric shock and leakage.
Shunt release has protection functions of overload, circuit, leakage, undervoltage, overvoltage, unbalance, under frequency, over frequency, reverse power, phase sequence; it also has functions of load monitor, real-time measurement, demand measurement, harmonics measurement, meters setting, maintenance, communication, DI/DO, regional selective interlock, test interlock, LCD interface display and so on.

Classification of releases

①, Electromagnetic release only provides magnetic protection, which is short-circuit protection, which is actually a magnetic return force, when current of the electromagnetic release is enough large to produce magnetic force, which overcomes the reaction spring pulling in armature and striking traction rod to drive mechanism action to cut off the circuit.
②, Thermal magnetic release provides magnetic protection and thermal protection, thermal protection is overload protection. Thermal protection: When the current through the release, thermal elements heating(direct thermal current directly through the bimetal), bimetal is heating and deformed, when the deformation to a certain extent, striking traction rod to drive mechanism action to cut off the circuit. In general, the circuit has thermal magnetic release to provide short-circuit and overload protection, only in some special occasions, the electromagnetic release provides short-circuit protection, and other components (such as thermal relays) provide overload protection.
③, Electronic release can have all the above functions, and can be easily set. Electronic release is the circuit composed of electronic components, for the main circuit current detection, to amplify and promote the trip mechanism.

Advantages and Disadvantages of Three Types of Release

①, The shortcomings of the electromagnetic release are protection of short-circuit, its advantages are low cost, long life, little environment affection.
②, The shortcomings of thermal magnetic release are two sections protection; action value error is relatively large, can not be adjusted (now called a new generation of circuit breakers can be mechanical adjustment, but the adjustment is small, and the error is quite large); easy to be impacted by the environment. Its advantages are low cost, stable performance, relatively high reliability, free from voltage fluctuations, long life, some models can be inverted into the line.
③, The advantages of electronic release is that it can provide three or four sections of protection; high sensitivity, action value is more accurate, and can be adjusted; can be connected with the host computer after the installation of communication modules, for remote control; little ambient temperature effects. Other shortcomings is that the cost is too high, and the reliability of domestic products is not high, generally can not be inverted into the line.

What is no-voltage release

No-voltage release is in parallel with the circuit breaker power supply, can play a protective role in under-voltage and zero voltage. When the power supply voltage is normal, the operating handle is pulled, the normally open auxiliary contact of the circuit breaker is closed, the electromagnet is energized and the armature is attracted by the electromagnet, the free tripping mechanism can lock the main contact in the closing position, and the circuit breaker is put into operation. When the power supply side is power off or power supply voltage is too low, the electromagnetic force generated by the electromagnet is not enough to overcome the reaction force of the spring tension, the armature is pulled up, to promote free tripping mechanism to make the circuit breaker trip by transmission mechanism, and to protect under-voltage and zero-voltage. When the power supply voltage is the rated voltage of 75%~105%, the no-voltage release ensures pull-in to make the circuit breaker close. When the power supply voltage is lower than the rated voltage of 40%, no-voltage release ensures tripping off to make the circuit breaker trip.
In general the normally closed button connected to electromagnetic coil circuit of no-voltage release in series can also do the opening operation.

What is the auxiliary contact

Auxiliary contact is mainly used for telecontrol at the control circuit for AC 50Hz, rated voltage 660V and below, DC rated voltage of 220V and below , or according to requirement of GB14048.4, access to the main circuit as contactor.
Structure Overview:
①The product has full plastic snap-fit assembly structure, make full use of the inherent elasticity of nylon itself, do not need screws and special tools for assembly and disassembly, labour-saving, time-saving, energy saving.
②The product has a direct-moving structure, and the reaction spring adopts a pagoda-type spring. The operating characteristic is reliable , the mechanism is flexible, the product has compact design, which can prevent the outside debris and dust falling into the product. The moving parts terminal are covered by a cover, people can't touch the electric parts, to ensure the use of safety and meet the relevant electrical safety standards. Product size is compact, installation area is small, installation has screw fastening or card button installed on 35 mm wide standard guide, demolition is quick and easy.
③The product contacts have double-break bridge structure. Contact is made of silver-based alloy material, excellent contact performance, wear resistance, long life, closed arc chamber is made of flame-retardant materials to prevent the arc splashing outward and to provide the safety of person and adjacent electric.
④The magnetic system of the product is E-shaped core , reliable, low loss, low noise, high mechanical strength, coil terminals A1, A2 printed with voltage specifications that clearly visible, easy wiring.
⑤Modular and blocking structure of auxiliary contact has flexible usages according to the need.

When ordering, please indicate the following points:
Model and name: such as MV + MN over-voltage release
Matching products: DZ47-100 matching
Order number: such as 5888 .
Order example: MV + MN over-voltage release, DZ47-100 matching, 2777.

Keywords: Shunt release , Circuit Breaker accessories