Switches with a dimmer are becoming more and more popular. These devices are designed to regulate the consumer voltage in the range FROM 0 to 100 percent of the nominal value. Now they are increasingly used instead of classic switches to smoothly change the brightness of the luminous flux.
Content
- Application area
- Dimmer classification
- Design features
- Principle of operation
- Advantages and disadvantages of dimmers
Application area
Most often, these devices are used to control the brightness of the glow of halogen bulbs and classic incandescent bulbs. Moreover, in the first case, there is one nuance of using the dimmer switch - it must be connected to the light source exclusively through a step-down transformer. This device can be purchased separately or you can use a turnkey solution.
It should also be remembered that special switches are produced that regulate the brightness of the light of LED and fluorescent lamps. The fact is that there is one important element in their design - an electronic starter. Thanks to the use of dimmers instead of conventional switches, it is possible to smoothly change the intensity of the luminous flux from minimum values to maximum values.
This is not only convenient, but also eliminates the need for multi-button switches to control chandeliers with multiple bulbs. The situation is the same with the complexand lighting devicesequipped with their own regulators - it is much cheaper to purchase a dimmer and connect a chandelier to it.
Dimmer classification
Today, there are three main types of monoblock adjustable light switches on sale:
- Devices equipped with a mechanical regulator made in the form of a disc - their design is very simple, which has a positive effect on cost. They can have a push or rotary switching mechanism.
- Dimmers with push-button adjustment - have a more complex design, but at the same time the functionality is expanded, for example, control can be carried out using the remote control.
- Touch devices are the most expensive dimmers with the widest possible functionality.
On sale you can find not only monoblock switches with a dimmer, but also devices with a modular design. The control of such dimmers is carried out using a rocker switch or a remote button. They are practically not used in residential premises.. Choosing a dimmer, you need to pay attention to the power of the device. This indicator must exceed the total power of all consumers connected to the switch.
A few words should be said about the additional functionality of dimmers:
- The ability to create the effect of presence.
- Several dimming modes, including flashing light.
- Automatically turn on and off.
- Remote or voice control.
Design features
This is a rather complex device when compared with classic switches. The main element of the design is the electrical circuit, the task of which is to reduce the voltage to the required value to power the dimmer. To ensure reliable and uninterrupted operation of this circuit, manufacturers use several types of protection, for example, against voltage surges in the network and overheating.
The main element of the circuit is a bi-directional thyristor thyristor. It is an electronic switch that controls a short pulse. To give a signal to open-close the thyristor, a capacitor with a certain capacity is used. During the passage of the first wave of the supply voltage, it accumulates a charge, after which it gives it to the thyristor.
Principle of operation
All modern dimmers are not consumers of electrical energy - this is their main difference from the first models. Earlier analogs worked in accordance with a capacitive or active voltage divider circuit. In fact, they were autotransformers or rheostats connected in series with the main energy consumer.
In each of the considered situations, production and use dimmers was quite costly. For example, if a rheostat was used, then this increased the mass of the entire device, and also led to strong heating. As a result, manufacturers had to look for ways to efficiently dissipate heat, and this affected the cost of the dimmer. The autotransformer, although it is not an active consumer of energy, has large dimensions.
In modern regulators of luminous flux power, a special electronic circuit is used, allowing to supply power to the lighting device, "cutting" the back and front of the half-wave voltage. This principle of operation of dimmers is called "phase control with cutting off the trailing and leading edges". In accordance with the operating mode, determined by the response time (this figure is 0-9 ms), it is possible to achieve smooth regulation of the power consumption.
Advantages and disadvantages of dimmers
Among the positive properties of all devices of this type, it is worth noting:
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Smooth change in the brightness of the light. - The consumer voltage is reduced without power dissipation, which leads to savings in electrical energy.
- Due to the operation at reduced voltage, the life of the bulbs is increased.
- Dimmers to a certain extent are able to protect the consumer of electricity from voltage drops in the network.
- A sharp increase in the current indicator when the light bulb is turned on is eliminated.
However, dimmers have several disadvantages:
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Higher cost in comparison with classic switches. - The supply voltage curve is somewhat distorted, but this does not greatly affect the result incandescent lamps.
- If the dimmer replaces the multi-button switches, it may be difficult to acquire the appropriate device. This is due to the cost of dual dimmer models or the need to equip new points for mounting devices.
If we are talking about connecting a single dimmer, then there should be no problems. During the installation of such a device, there is no need to make changes to the wiring diagram of the apartment. If a person at least once changed the switch, you can easily connect the dimmer, because the marking of all the terminals is the same.
