From correct connection of wiring in the house depends comfortable accommodation of all its inhabitants, and trouble-free operation of appliances. Do you agree? To protect equipment, located in the house, from the effects of over-voltage or short circuit, and the occupants from the hazards associated with electrical shock, it is necessary to include in the circuit protective devices.
It is necessary to fulfill the main requirement - to connect the RCD and the machines in the panel must be done correctly. It is equally important not to be mistaken with the choice of these devices. But do not worry, we'll tell you how to do it right.
In this article, we will focus on that on what parameters are selected RCD. In addition, here you will find particular rules connect machines and RCD, as well as many useful schemes to connect. And given the material videos to help implement all in practice, even without the involvement of experts, if you are even slightly versed in electrical engineering.
The content of the article:
- Basic principles of connection
Selection of RCDs on the main parameters
- Criterion # 1. The nuances of the selection device
- Criterion # 2. Existing types of RCDs
Installing the RCD and machines in shield
- The main rules of connection
- Features wiring diagrams
- Details on a simple scheme
- Option to connect machines without RCD
- RCDs in the three-phase network
- RCD and three-phase machines on board
- Conclusions and useful videos on the topic
Basic principles of connection
To connect the RCD panel needs two conductors. On the first of these current flows to the load, and the second - out of the consumer at the perimeter.
As soon as the leakage current, there is a difference between the values at its input and output. When the result exceeds the predetermined value, RCD It operates in emergency mode, thus protecting the entire apartment line.
On devices tripping negatively affect short-circuit (short circuit) and voltage variations, so they need to be covered. Problem is solved by including in the machine circuit.
As part of the RCD has a ring-shaped core with two windings. In its electrical and physical characteristics are identical windings
Current feeding electrical enters through one of the windings of the core in one direction. The other direction, he has a second winding after passing through them.
Self Installation of protection devices is to use schemes. As the RCD, modular, and vending machines are installed in the panel.
Before starting the installation you need to solve the following questions:
- as the RCD should be installed;
- where they should be in the scheme;
- how to connect to the RCD is working correctly.
Rule wiring states that all connections single-phase network should be included in the connected devices from the top down.
Professional electricians explain this by saying that if they start from the bottom, then the efficiency of the vast majority of machines will drop by a quarter. In addition, masters of the shield, do not have to further understand the circuit.
RCD designed for installation on the individual lines, and having a small nominal values, in the overall network can not be mounted. In the case of non-compliance with this rule will increase the likelihood of leaks and faults.
Selection of RCDs on the main parameters
All technical details related to the choice of the RCD, is known only to professional installers. For this reason, experts should make the selection of the devices is still in the development of the project.
Criterion # 1. The nuances of the selection device
When selecting a device rated current acts as the primary criterion for passing therethrough in extended modes.
Based on the stability parameter - the leakage current, there are two main classes RCD "A" and "AS". the latter category phones more reliable
In magnitude is in the range 6-125 A. IΔn residual current - the second most important characteristic. This is a fixed value at which triggered RCD. When it is selected from the group of 10, 30, 100, 300, 500 mA, 1 A precedence safety requirements.
Influences the choice and goal setting. To ensure safe operation of the device are oriented to the nominal current value with a small margin. If protection is needed for the house as a whole or for the apartment, all the loads are summed.
Criterion # 2. Existing types of RCDs
It is necessary to distinguish between the RCD and by type. There are only two - Electrical and electronic. The main operating unit of the first - with magnetic winding. Its effect is to compare the current values of the outgoing network and returning back.
There is a function in the second type of machine, only performs its electronic board. It works only in the presence of voltage. Because of this electromechanical device protects better.
In the apparatus of the electromechanical type has a differential transformer + relay, while the electronic type RCDs present electronic board. Herein lies the difference between them
In situations where the user accidentally touches to the phase conductor and the board will be de-energized in case of an electronic RCD setup man will come under pressure. In this case, the security device does not work, and electro-mechanical in such conditions will remain operational.
Subtleties selection RCD described in this material.
Installing the RCD and machines in shield
Block, which contains the account of the load and the distribution device, typically a base for mounting the RCD. Regardless of the chosen scheme, there are rules required when connecting.
The main rules of connection
Along with automatic shut-off device mounted on the flap and machines. All you need for this - a minimum of tools and competent scheme.
Standard kit should contain:
- Screwdriver of packet;
- side cutters;
Also required for the installation of cable VVG different colors, chosen in the cross section in accordance with the currents. PVC insulation tube operate marking conductors.
When on DIN-board available on board, there is a place, it mounted a residual current device. Otherwise, install additional.
A key principle of the installation is as follows: a neutral conductor contact after the RCD or the input zero or grounding is unacceptable, so it is isolated by analogy with other conductors.
Consistently with the RCD circuit breaker should be included. It is also one of the most important rules.
When protection of the whole housing is formed with one RCD circuit is used, comprising several machines.
In order to exclude the presence of additional conductors on the board that does not look very aesthetically pleasing, comb (distribution) is used to connect the beam lived bus
The project includes, in addition to additional AB, another component - insulator Zero tires. Mount it on a body panel or din-rail.
Enter this supplement due to the fact that a large number of zero conductors connected to the output terminal of the trip device, they just do not fit in one setting. Isolated bus zero - the best way out of this situation.
Sometimes electricians to put a whole bunch of zero wire in the socket, take a decision on filing lived single cable. In the case when the cable is stranded several veins are removed.
This option is not used because of the decrease of the cross section will increase the resistance of conductors, consequently, to increase heating.
As the number of mounting holes, and their diameter may be different. The tire is mounted directly on the earth body.
Neutral wires in one twisting - additional inconvenience in detecting damage to the line, and when it is necessary to dismantle one of the cables. There do without unscrewing the clamping unwinding the harness that is required to trigger the appearance of cracks in the veins.
Do not install synchronously and the two wires in the same nest. Inputs breakers linked jumpers. As the latest in professional installation using special docking bus called "comb".
Features wiring diagrams
Selecting the scheme involves consideration of the specific features of the electrical network. Among the many options there are only two schemes, which are used to connect the machine and the RCD panel, Shall prevail.
The simplest machines arrangement and a protective device. It can be used to connect from one to several loads connected in parallel
In the first and simplest method, when one RCD protects the entire electrical network lie disadvantages. Basic - difficulty in identifying the specific fault location.
Second - when there will be a failure, the whole system will be out of operation in the functioning of the RCD. Residual current device location is withdrawn immediately after the meter.
The following method provides for such devices on each individual line. Fail over to one of them, all the rest will be in working order. To implement this scheme requires a marker panel and the high cost in financial terms.
Details on a simple scheme
Consider RCDs connection with machine guns on a simple apartment shield. At the entrance stands a two-pole automatic inclusion. To this two-pole RCD is connected to which two single-pole machine.
To the output of each load is connected. In principle RCD also introduced into the circuit as circuit breaker.
On the case there is an RCD "Test" button. It is intended for testing its operation. Manufacturers are advised to at least once a month using this button and check the operation of the device itself
Phase supplied to the Automatic Transfer Switch, comes to the RCD input with output to machines. The zero output of the automaton goes to zero bus, and from it - to the input of the apparatus.
With its output zero conductor already sent to the second zero bus. In the presence of the second bus, and is a special nuance, not knowing where it is impossible to achieve the proper functioning of the circuit.
RCD during operation controls both incoming and outgoing voltage - how many have gone to the entrance, so should be the output.
If the equilibrium is disturbed, and the output is more than the value of the setting, which is set RCD is its operation and auto power off. During this process exactly corresponds to the zero bus.
In electrical circuits, which is not provided for mounting the unit breaker, only one common zero.
In circuits with RCD picture is different - there is already present a few of these zeros. When using one of the two devices - and the overall relative to which the protective device operates.
If you have two RCDs - zero three tires. Denote their indices: N1, N2, N3, etc. In general, zero is always one more than the circuit breakers. One of them is the main, and all the others are tied directly to the RCD.
Color coding of the electric wires according to the rules established by the SAE. This marking must study before proceeding to the installation of protective devices
If you intend to connect via the RCD not all of the equipment, then zero is supplied with a common bus. Residual current device in this case is excluded from the circuit.
When adding a single-pole machine operating from the RCD, the output of the last stage is fed to the input of the circuit breaker. From the output of the switch conductor connected to the one load terminal. Zero it is supplied to the second terminal. He arrives with zero tire, created by the RCD.
On board there is one more element - the tire safety ground. Correct operation of RCD is impossible without it.
Wire network is available only in new homes. It is required to present a zero phase and ground. The houses built long ago, there is only a phase and zero. In such circumstances the RCD will also function, but a little differently than in the three-phase network.
As a way out grounding terminal of the third conductor in the socket, and then up at the ceiling to the place where the connected lamps. For circuit breakers "earth" does not serve.
Option to connect machines without RCD
There are occasions when one of the machines you want to connect, bypassing the residual current device. Power supply is connected from the output of the RCD, and to enter it, i.e. directly to the machine. Phase is input, and its output is connected to the left terminal load.
Zero take zero general bus (N). If damage happens at the site, controlled by the RCD, it will be removed from the circuit, and the second load will not be de-energized.
RCDs in the three-phase network
In a network of this type include special or three-phase RCD with eight contacts, or three-phase.
Place the wiring diagram of the RCD on its case. Wires extending from the output terminal is supplied to the distribution networks apartments
connection principle is identical. Mount according to its schema. Phases A, B and C provide power to the load, calculated at 380 V. If we consider each phase separately, in tandem with the cable N (0), it provides a series of single-phase 220 V.
Manufacturers produce three-phase tripping of protection devices, adapted to high leakage currents. They protect the wiring only on fire.
The photo two schemes: disconnection protection device in single-phase and three-phase mains system TN-C-S. This means that the cable is divided into zero-working and protective
In order to protect people from the effects of electric current on the outgoing branches mounted single-phase two-pole RCD configured to leakage current between 10-30 mA. To cover the machine is inserted in front of each. In the circuit after the RCD may not be combined and ground working zero.
RCD and three-phase machines on board
Let us examine in detail is not quite a standard circuit on the three-phase supply panel.
- three-phase input breakers - 3 pcs .;
- three-pole earth leakage circuit breaker - 1 ps .;
- single-phase RCD - 2 pcs .;
- single-pole single-phase machines - 4 pcs.
From the first voltage induction machine is supplied to second three-phase machine terminals through the upper. Hence, too, one phase is the first single-pole RCD, and the second - the next.
Voltage from the second input automaton goes to the three-phase RCD, the lower terminal of which is connected three-phase load. This security device prevents leakage currents, and the second induction machine - the short-circuit
Single-phase RCD installed on the panel, are bipolar and automatic - single-pole. For correct functioning of the safety device is necessary to work the zeros after it anywhere else not connected. Therefore, after each RCD she is a zero bus.
When the machines are not one, but two-pole, the individual will not have to set the zero bus. If two zero tires combine, will be a false alarm.
Each of the single-pole RCD calculated on two machines (1-3, 2-4). To lower the load terminals connected machines.
A common ground bus mounted separately. In the automatic opening come three phases: L1, L2, L3, neutral wire N working and PE - protective.
Zero is connected to a common zero, and with it goes all the RCD. After he goes to the load: a first device - on a three-phase and single-phase with the following - each in his bus.
In the three-phase electric vector quantities, so their total value is determined not algebraic, and the vector sum of these values
Although this three-phase input supply panel, separation of the wires on PEN and PE is not satisfied because five-wire input. On the shield comes three phases and ground zero.
Conclusions and useful videos on the topic
Nuances of the installation of all the elements on the housing panel:
Details RCD installation:
RCD and machines - machines are technically complex. It is advisable to install in places where electricity can pose a threat to both the safety of people and home technology.
Mounting it involves consideration of many parameters, so the calculation, and the installation is best made by qualified technicians.
If you have experience of self-assembly RCD, please share it with our readers. Tell us what points should be emphasized. Leave your comments, ask questions in a section block.