What is a power limiter and what is it for?
Acquaintance with the device
The design of the power limiter may consist of various element bases:
- electromechanical induction relays;
- solid-state (semiconductor) elements;
- microprocessor controllers.
Due to the presence of programmable microcircuits, the limiter can boast a wide range of settings, which makes it easy to operate. Adjusting the module is quite simple. In some models, you can control the power through the installed display.
Where is OM used and why is it needed
The automatic limiter has to control the electrical power when it is sharply increasing, or turn off the power when it is sharply lower. The use of such devices is advisable both in apartments and in private houses and in administrative buildings.
Generally speaking, why do we need an electric limiter, we should mention its main features:
- To control incoming electricity, in cases of surges of which the current supply is interrupted, which will help household appliances to avoid overloads.
- Protect your power supply from third-party connections. Today, it is considered common to connect another subscriber to a personal cable, which, therefore, is involved in the theft of electric current. In this situation, the limiter, due to the clearly established number of subscribers and power consumption, can prevent the problem of illegal connection.
- Manage a variety of mechanisms. The device can control the power of an automobile engine, machine tools, microwave ovens and other devices. Sometimes OM is found on scooters, in emergency circuits.
You can learn more about the purpose and scope of the power limiter in the video:
By the way scope and purpose of the voltage relay have similarities with OM, therefore, we recommend that you familiarize yourself with this information after reading the article!
How does the device work?
The limiter continuously monitors the state of the mains, especially at high loads. At the moment of exceeding the network energy consumption set by the owner, the device automatically “blocks” the load circuit line.After a certain time period set in advance, the limiter will automatically resume the supply of electricity to the line and, if the consumption has dropped below a critical level, the load circuit will continue to be connected.
OM design is represented by several functional blocks. So the measuring unit collects information on energy consumption due to voltage and current sensors. Based on these data, in the logical “center” of the device, the exact power value that is currently available is calculated, followed by its comparison with the potentiometer and the parameters set by the subscriber as the maximum possible (critical) ones. If the current power “fits” to critical values, then a signal will be sent to the executive circuit from the computing unit to disconnect the excess load. This command will be executed by the contactor immediately.
After the OM is triggered, the user needs to switch to disabling additional devices, the operation of which could lead to the excess of the established electrolyte. After the set time has passed, the limiter will give a command to turn on and continue to monitor the power in normal mode.
You can adjust the power (its critical value), the shutdown time, as well as the re-enable, thanks to the potentiometers. The terminals have two groups of terminals - for connecting power and for adjusting load on / off. The built-in contactors tend to differ in voltage and current, so it is possible to use external contactors.
In certain models, a function is provided that controls the connection of only priority loads. Non-priority loads are disconnected. As you can see, the operating principle of OM is quite complicated, because there is a computing unit, thanks to which the power is controlled.
Features of connection and settings
The correct connection of the limiter is very important. Please note that a device having one phase is connected to only one contactor. A device with three phases - to several. Otherwise, there is a risk of “killing" the limiter due to incorrect connection to the output terminal.
Almost every OM, which is an adjustable device, has a built-in transformer. To connect it requires pulling the network cable through the transformer. Therefore, power and voltage are calculated according to the local power supply. The connection diagram of a specific device can be found in his passport. For example, the OM-110 model can be connected as follows:
Basically, both in euromatics and in “our” instances, there is access to an independent determination of the current cutoff speed in cases when the network power is exceeded - the limiter has a corresponding function button. If you wish, you can "delve" into the factory settings, changing them in accordance with personal preferences.
In order to ensure maximum density of the mount and so that the device does not “overload” the shield panel, it is recommended to install it on a DIN rail, as shown in the photo below. After installation, you should configure the device according to the manufacturer's recommendations. The choice of optimal power is determined by the needs of users. If connected correctly, the “Load” diode will turn green. If this does not happen, it is necessary to check the correct connection with the contactors.
Often, a shield with OM (SHCHOM) is installed with subsequent installation of the meter on it. Such a system is used to significantly reduce the time required to install individual devices, as well as to "hide" protruding wires and save space in the shield.
That's all I wanted to tell you about the device, the principle of operation and the purpose of the power limiter. We hope the material provided was useful and interesting for you!
It will be interesting to read:
Loading...
