Electricity is very crucial in our modern life. People integrate electrical power for cooling, heating, refrigeration, lighting, and operating appliances. Also, it is widely used in operating machinery, electronics, and transportations systems. The consumption of electricity keeps increasing as new machines and electronics are being produced.
We consume electricity daily. However, there is a need to control electrical power. Electrical power control is a core part of electrical power system operation. In electrical systems, control is very complex. Therefore, it is important to limit the subject of this discussion to some of the types of equipment used for electrical power control.
What is Electrical Power Control System?
The electrical power control system comprises automated devices that regulate the distribution, transmission, and transformation of electrical energy in equipment. Also, these systems regulate electric current flow required for proper operation. Electrical power control system helps to maintain stability of electric current and makes equipment easy to operate. Also, the mechanism of electrical power control should be efficient in every control phase.
There are some machines that operate due to many devices responding to an electrical control system. For example, electricity conductors for pumps and motors or control switches. The electrical power control system is of great importance in various sectors like airplanes, industries, and ships. From construction to engineering and industrial, electrical control systems function well to ensure all processes and setups comply with their mechanical functions.
Furthermore, electrical power control is implemented to minimize environmental impact and economic costs. It helps in balancing the demand and supply of electrical power. The electrical power control system offers quality energy by putting basic conditions like supply continuity, voltage, and frequency into consideration.
All electrical power control systems comprise some elements. These are conductors, generators, surge protectors, receptors, and control elements. Control and maneuvering elements are devices that open or close a circuit. Electrical power control reacts to incoming signal from an electrical variable and then applies controlling function.
To have a better understanding of how electrical control systems work, we have explained better. Electrical control systems comprise sets of mechanical and electrical devices. These systems integrate output and input control models to control the characteristics of dynamic systems. Electrical power control systems are at the heart of automated system to enable proper operation.
Power Control with Switches
Switches are important elements of electrical power control. Here, we will be examining the various types of switches integrated in electrical power control. A switch is mainly designed to turn on or off a circuit. However, switches can perform more complex functions. In this section, we will focus more on switches integrated for motor control.
Types of switches
Rocker switch
Rocker switches are mainly integrated in on-off control. They can accomplish a stable contact or temporary control. Also, they can make a load stay in an on or off condition until the position of the switch is changed.
Rotary switch
This type of switch allows the wiring of many different switching combinations. The rotary switch has a shaft which is fixed to sets of moving contacts. The moving contacts make contact with sets of stationary contacts when you turn the rotary shaft to various positions. Also, this shaft can lock into any location. You can control rotary switches manually by turning the rotary shaft anticlockwise or clockwise. To make the turning of the shaft easier, a knob is usually attached to the end of the rotary shaft.
Temperature switch
This switch is one of the most popular control devices integrated in industry. A temperature switch has a control element which features a particular amount of liquid. When there is an increase in temperature, the volume of the liquid increases. Therefore, the location of a set of contacts can change in response to changes in temperature. It is possible to adjust temperature switches throughout varying temperature settings.
Toggle Switch
The toggle switch is one of the simplest types of switches. This switch has various symbols and control functions. It is crucial to know the control functions of each toggle switch and what that they can accomplish.
Limit Switch
Limit switches are available in a wide range of sizes. These are on/off switches that integrate a mechanical movement to change the operation of a motor’s electrical control circuit. The mechanical movement develops an electrical current which limits the movement of the machine. Furthermore, limit switches are usually integrated in counting, routing and sequencing operations in industry. These switches are used along side electrical re lays, hydraulic or pneumatic controls.
Pressure Switch
A pressure switch is an electrical power control devices that comprises electrical contacts that change states due to varying pressure of air, water, and hydraulic fluid. Some pressure switches depend on the intake or discharging of a medium. There is another type of pressure switch that integrates a piston mechanism to open or close the switch contacts. The pressure of the medium controls the movement of the piston.
Electrical Power Control Using Relays
Relays are used for controlling electrical power. There are various types of relays.
General-purpose relay
A general-purpose relay is ideal for use in low-power applications. This relay is small in size and inexpensive. Most general-purpose relays are installed in 8-pin plug-in sockets.
Latching relay
This is another type of relay integrated in electrical power control. A latching relay has a latching mechanism that keeps the contacts in position. Also, this type of relay features a type of unlatching coil linked in series with a switch.
Solid-state relay
This relay is necessary for enhancing reliability and the rate of operation. A solid-state relay has a long life span. Also, this relay can withstand corrosion, vibration, moisture, and shock.
Timing relay
A timing relay turns on or off a load device after a particular period.
Control Equipment that Suit Electric Motors
The power of electric motors can be controlled by a variety of electromechanical devices. The machinery’s performance and the effectiveness of this power-system operation will be impacted by the choice of the power-control equipment. Using the appropriate equipment for every power-control application is crucial. The apparatus utilized for the motor control will be the main focus of this section.
Motor-starting Control
The motor-starting mechanism is a form of a power control being used in accelerating a motor out of a “stopped” position to its usual running speed. The simplest motor starter is a manual on/off switch linked in series including one or even more transmission lines. There are numerous other types of motor starter designs.
Only smaller motors with modest current requirements can use this kind of starter. The magnetic starters are different kinds of motor starters that uses electromagnetic effects in opening or closing the motor’s power-source circuit. In the industrial plant, motor starters were frequently clustered together for management of nearby equipment.
Control centers are such collections of the motor starter as well as related control hardware. As they are generally small as well as their control equipment isn’t dispersed over a large region, control centers make it relatively simple to access the electrical distribution system.
Motor Starter Functions
To manage the power of a motor, different motor starter types are employed. The complexity of a starter’s functions varies; Nevertheless, motor starters typically carry out at least one of these tasks:
- Acceleration
- On/off control
- Overload prevention
- Reversing the rotation’s direction
Some starters work by connecting them directly throughout the lines of the power input to control the motor. In order to lower the amount of beginning current, other starters lower the input voltage which is applied towards the motor once it’s started. Usually, this magnetic contactor and the overload protection of the motor are housed within a single enclosure.
Manual Starters
Manual starters are used by some motors to regulate their operation. Similar to the magnetic contactor, this kind of starter offers starting, stopping, as well as overload protection. Manual starts must, however, be installed close to the motor which is to be controlled.
It isn’t possible to operate the device remotely, as with the magnetic contactor. The reason for this is that this magnetic contactor only needs a minimal control current. By dropping off the contacts whenever the low-voltage level occurs, magnetic contactors can offer low-voltage protection. Unless they’re turned off manually, manual starters stay closed. They often come in just small sizes.
Why Electrical Power Control Systems are Crucial?
Electrical power control systems are of great importance in various industries as they play significant roles in any application. Form oil and gas to construction, industrial, and engineering, there is a need to implement electrical power control systems. In modern facilities, these systems are implemented to direct the functions and operations of different equipment.
Reduced safety risk
Safety is very important in any industrial operations or processes. The implementation of heavy machinery poses huge risk to human safety, particularly if workers need to interact with manual equipment for cleaning and maintenance. Therefore, it is much safer to incorporate automated and electronically controlled processes as they pose less risk to workers. Also, it helps plant operators to strictly comply with all the safety regulations and rules in the industry
Lower costs
It is easy to predict and detect possible issues since automated systems use a huge amount of real-time data. There is a need to address these issues before they become bigger. Electrical control systems help to predict and make corrections to variables. This helps to ensure the smooth running of processes and equipment and as well detect any performance problems caused by deteriorating components.
Also, electrical control systems reduce downtime as it is possible to predict any need for maintenance Furthermore, huge amount of data can be recorded for future analysis. This will help performance investigations in the future.
Energy savings
One common issue faced by most production facilities is energy consumption. Operators are constantly on the look out, seeking for ways to minimize energy usage in order to maximize efficiency. The majority of plant equipment is now integrating devices to monitor every phase of a production process. Operations can become more efficient and precise with the implementation of electrical control system.
Increased flexibility
Electrical power control systems offer more adaptability and flexibility production processes. Also, these systems can be easily and quickly reprogrammed with new production tasks to enhance changeovers or new product delivery.
Consistent quality
When electrical power controls are integrated in automated systems, it helps in minimizing the requirement for human interaction. In the long run, this reduces the risk of human error. Since automated systems are controlled with more precision, it becomes possible to achieve more consistency and improvement in output quality. Furthermore, you can run these systems at the same level of performance.
How to Protect Electrical Control System
Electrical control systems need to keep supplying power. Any disruption in power supply will affect the energy distributed or consumed. Therefore, it is important to protect electrical control system. Below are ways to protect the electrical control system.
Generator set
A generator set is usually integrated when fixed installation or a general network can’t operate on its own.
Automatic transfer
Here, the control systems have more than one electrical energy source. This is necessary in case one of the sources fails. If there is failure in a source, it switches it out and another source supplies power.
Uninterruptible power supply (UPS)
A UPS comprises a system that uses batteries to keep the control system running while fixing the possible supply problem.
Conclusion
All electrical power control systems comprise some elements. These are conductors, generators, surge protectors, receptors, and control elements. Control and maneuvering elements are devices that open or close a circuit. Electrical power control reacts to incoming signal from an electrical variable and then applies controlling function.
Electrical power control systems are of great importance in various industries as they play significant roles in any application. Also, these systems monitor and regulate process variables to enable production processes run in an effective way. These systems offer a high level of flexibility and adaptability in production processes. Also, they help to increase safety, enhance productivity and efficiency.
