Differential Circuit Breaker - Connection Diagrams and Features
Modern home appliances that are sensitive to voltage fluctuations are connected to the power supply network in private houses and apartments. Current surges and a short circuit in the wiring disable electrical devices that require stable power. In case of accidental contact of a person with devices under voltage, there is a high probability of death. To prevent the occurrence of problematic situations allows the differential circuit breaker, which is important to properly connect in the distribution panel to the power circuit.
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ix differential circuit breaker
Emergency circuit breakers is an electromechanical protective device for the following purposes:
- off voltage for short circuit wiring in the network;
- protect consumers of electrical energy from voltage fluctuations;
- prevent power supply in case of emergency leakage current.
In the general case of the differential automaton, a compact residual current circuit breaker and circuit breaker are combined.
Differential automaton consists of two protective devices In case of contact of a person with current-carrying elements of electrical devices and bare wires, it acts as a protective shutdown device, instantly de-energizing the power supply circuit.
In case of overload caused by switching on powerful household appliances or external factors, as well as in the event of a short circuit, the device turns off the power supply. In this situation, it functions as a differential current switch.
Principle and methods of operation of the difavtomat
The protection module integrated into the device is a circuit breaker that shuts off the network when the zero core contacts the phase conductor and is overloaded by consumers. The tripping mechanism opens the contact group when the circuit is closed and voltage surges. The protection device is equipped with a reset button, manual pressing of which returns the shutdown mechanism to its original state.
The principle of operation of the automat. The main element of the differential protection unit is a small-sized transformer. It provides a continuous comparison of the magnitude of the current at the input section and the output circuit, ensuring the protection of people from electrical damage.
In the event of significant fluctuations that pose a threat to life, protection automatically triggers. The principle of operation of a protective device, including a compact electromagnet, a differential transformer and a shutdown mechanism, is based on the conversion of electrical energy into mechanical force. At current surges the circuit is broken by mechanical action.
Video: principle of operation and the device of the differential automatic device
Connection scheme
To protect the household wiring, the device can be connected in different ways. The device connection variant depends on the number of phases, the presence of grounding, the installation location of the machine and the characteristics of the room( moisture concentration).
Conventional
The traditional way to connect a typesetter provides for the general protection of a group of electrical circuits with one device connected after the counter on the input line.
A circuit breaker in the input circuit ensures complete disconnection of all circuits in an emergency. The supply voltage is supplied to the upper terminal block of the device, and the connection of the consumer group to the lower terminals. In all circuits with consumers pre-included circuit breakers.
This scheme is simple, but has a significant drawback - the complete de-energization of all circuits during an emergency shutdown of the line by a differential automatic.
You can avoid spurious trips of input protection by installing such an automaton that operates with a leakage current of 30 mA.
For wet rooms
To ensure reliable protection of the electrical network and appliances located in rooms with a high moisture concentration( kitchen, bathroom and shower room), use the scheme of separate connection of differential automata. They connect in different circuits and provide separate protection for consumer groups located in different rooms.
Option of individual installation of two difavtomat to protect individual circuits Advantages of the scheme - the ability to quickly search for faults and restore the power supply to the damaged section. The disadvantage is the costs associated with the need to purchase and install an additional protective device.
The proposed scheme is distinguished by increased reliability and ease of use. When any differential automaton is triggered, the rest continue to function and no electrical power is disconnected in other rooms.
Connection of an
difactomate When connecting a differential automatic machine according to the chosen scheme, observe the main rule: connect the neutral and phase wires of a specific electrical circuit to the device, which will be protected by a differential current circuit breaker. It is prohibited to connect the common bus of the neutral wires of the electrical circuit with the zero residential machine. Violation of the requirement will lead to the disconnection of the protective device caused by the different magnitudes of the currents flowing through the wires.
Circuit for a single-phase network( 220 V)
It is possible to provide reliable and convenient protection of a single-phase network with a voltage of 220 V, if you use a selective differential automatic switch.
Selective protection allows you to disable a separate circuit It performs a selective shutdown of the problem area of the electrical network. The machine is equipped with a shutdown delay mechanism. The design of the device provides the ability to change the value of the differential current, disconnecting the circuit from the load.
The general selective machine shown in the diagram, installed in the power supply circuit of three apartments, selectively disconnects the apartment with damage to the electrical network. In this case, the selective machine is in the on state. It protects the rest of the apartments, which are energized.
In a three-phase network( 380 V)
If it is necessary to protect the electrical network with a voltage of 380 V, a three-phase differential circuit breaker should be used.
The three-phase protection device has an enlarged terminal block for connection to the 380 V mains. The connection circuit of the four-pole protective device provides for the connection of three supply phases to the typesetter.
At the input and output of the circuit breaker, there are terminals for connecting phases and neutral wire. This connection option is used in cottages, private houses, garage rooms and repair shops that use powerful electrical equipment.
Without grounding
In old panel buildings and country houses an electrical network with two wires is used - phase and zero. In such a network, it is also possible to connect a differential automaton and protect electrical devices from voltage surges and short-circuits.
Without a grounding wire, the likelihood of an electric shock increases. However, the absence of a grounding wire increases the risk of electric shock when people touch live metal parts. Scheme can not be called safe. Having installed the device in accordance with the above scheme, in future, replace the electrical wiring with a new one, equipped with a grounding contact.
Installation Recommendations
Having decided on the wiring diagram of the differential automaton, proceed to the installation activities. The steps involved in connecting the protection device include the following operations:
- Visual inspection of the case status. Cracks and damage that may affect safety and impair the proper operation of the device are not allowed.
Once you are satisfied that there are no defects, you can continue installing - Turning off electrical energy in the room. Check the absence of voltage with a multimeter or indicator screwdriver.
Multimeter indicates that the voltage is not turned off. - Installing a differential automat in the switchboard. Check the reliability of mounting and the possibility of placing the necessary devices in the shield.
For installation, an - rail is used. Installation of additional electrical devices in the switchboard. Be guided when connecting the selected wiring diagram.
- Preparing the wires required for connection. Use blue wires for the zero circuit, yellow for grounding, and any identical color for phase circuits.
- Stripping of insulation coating on connecting wires. Use a special tool to remove the insulation to ensure the safety of the conductors.
A special tool allows you to easily remove the insulation - Connect the zero conductor and the phase conductor to the input and output connectors on the body of the circuit breaker, as well as the rest of the wires to the devices located in the shield. Check the reliability of fixing the wires in special connectors and compliance with the wiring diagram.
Proper connection - a guarantee of reliable protection - The supply of electrical power and the monitoring of the operability of the differential automaton.
After confirming the operation of the device, close the distribution box. Now you can safely operate indoor appliances and electrical equipment.
Video: Connecting an Differ
The video provides information on the connection and operation of the device.
Independent connection of a diphavtomat is a solvable problem. It is important to choose the right wiring diagram and properly install the protective device. It is advisable to use wiring diagrams that provide for the installation of a separate differential automaton for each group of consumers. Given the complexity of the device and the need to take into account the complex parameters, it is desirable to entrust the work of connecting a differential machine to qualified specialists. At the same time, there is no doubt about the safe and long-term operation of electrical equipment, household appliances, as well as reliable protection of people against electric shock.
