An actuator valve is a valve that opens & closes by electric torque. The electric actuator produces the torque. The actuator conveys the torque to its output shaft. It rotates the valve’s ball or disc. The actuator opens and closes the valve. It may allow intermediate positioning, too. Some actuator valves have switches.
Why Do We Need to Use AC/DC Actuator Valve?
The usage of electric actuators valve is necessary now. A lot of industries are using these actuator valves. These factories & industries have made a revolution in their production. A successful business now depends on technology. Actuator valves play a vital role in automation technology. It plays a positive role in the environment. Using electric actuator valves needs less energy to function. The most important thing is that it cuts down on operating costs. All kinds of process plants use valve actuators. Without a valve, we can’t imagine industrial or automated process control.
Operating Principle of Actuator Valve
Actuators are comfortable with 12 volts, 24 volts, and 48 volts DC. Among these, the 24-volt DC actuator valve is very popular. We can use a limit switch to control the current of this valve. It stops the current when the valve is fully closed or open. Modulation Control is necessary sometimes. Motors can control modulation. This can fix the position of the valve. Modulation control makes it easy. It happens at any point between opening and closing. It means the work between 0° and 90°. It is useful for a valve. It can adjust the flow rate through the valve. We can also use a positioning circuit board in the actuator. It helps to modulate the motor.
Various Types of Actuator Valve
Quarter-turn, Multi-turn & Linear electrical valves are the most used valves & actuators. These can be helpful for different purposes. The quarter-turn valve has a 90° turn to open and close a port. Linear-motorized ball valve works with control valves for fluid flow.
Selecting a suitable actuator valve depends on necessity. You should have a good knowledge of valves & actuators before buying or installing them. Few valves need a multi-turn actuator, few need a single-turn valve actuator, and few need a reciprocating valve actuator.
How to Choose an Ideal AC/DC Actuator Valve
An actuator’s most used driving energy source is the power or fluid source. A three-phase power source is handy for the large-sized valve. The small-sized valve operates through a single-phase power source. AC electric valve actuators are available in 24V AC, 220V AC, 380V AC, etc. DC power is also available. Batteries go with DC actuators. It ensures a fail-safe operation.
Understand Your Application:
- Purpose: Understand the primary function the actuator valve will serve in your system – whether it’s for controlling fluid flow, regulating pressure, or other purposes.
- Environment: Assess the environmental conditions where the actuator will operate. Consider factors like temperature, humidity, and potential exposure to corrosive substances.
- Operating Mode: Determine whether the valve will be normally open or closed in its resting state.
Determine the Specifications:
- Voltage: Choose between AC or DC voltage based on your system requirements and power supply.
- Power Requirements: Evaluate the power needs of the actuator to ensure it can perform effectively without overloading your system.
- Speed: Look at the speed at which the actuator operates to ensure it meets the needs of your application.
Analyze the Material:
- Corrosion Resistance: Select materials resistant to corrosion, especially if the valve is exposed to harsh or corrosive environments.
- Durability: Choose durable materials that can withstand the pressures and temperatures of your application.
Size and Dimensions:
- Size: Ensure the actuator valve fits within the physical space constraints of your system.
- Connection Size and Type: Make sure the valve connections match the size and type of the connections in your system.
Evaluate the Control Options:
- Control Type: Decide whether you need proportional control, on/off control, or modulating control based on your application.
- Control Signal: Determine the type of control signal your system uses, such as 4-20mA, 0-10V, or others.
Check Certifications and Standards Compliance:
- Ensure the actuator valve complies with relevant industry standards and certifications.
Consider the Manufacturer and Supplier:
- Reputation: Look for reputable manufacturers and suppliers with positive reviews and case studies.
- Support: Check if they provide technical support, warranties, and maintenance services.
Budget and Cost Consideration:
- Cost: Balance between quality and cost. Although cheaper options might be tempting, investing in a high-quality actuator valve can save you from potential issues and additional costs.
Additional Features:
- Look for additional features or technologies that might benefit your application, such as smart capabilities, diagnostic features, etc.
By carefully analyzing these aspects, you can select an AC/DC actuator valve that will meet your needs and provide reliable performance over time. It might also be beneficial to consult with a valve specialist or the manufacturer to ensure that the chosen actuator valve is the ideal fit for your application.
What’s the difference between AC and DC?
AC and DC refer to the two types of electrical current: alternating current (AC) and direct current (DC). They differ in the way they deliver energy and are used in different applications due to their unique properties. In the context of actuator valves, choosing between AC and DC is crucial as it affects the performance and compatibility with your existing electrical systems. Below is an outline explaining the differences and various voltage levels:
1. Alternating Current (AC):
- Direction: AC constantly changes direction and polarity. It alternates between positive and negative voltage, usually in a sinusoidal waveform.
- Voltage Levels: Common AC voltages include 110V and 230V.
- Applications: AC is the standard for transmitting electricity over long distances due to its ability to change voltage levels easily using transformers. It’s used in most household and industrial applications.
- Actuator Valves: AC actuators might have a higher starting torque and are often used in larger or industrial-scale applications.
2. Direct Current (DC):
- Direction: DC maintains a constant direction, flowing continuously in one direction.
- Voltage Levels: Common DC voltages include 12V and 24V.
- Applications: DC is more efficient for short-distance electricity transmission. It’s also used in low-voltage applications like batteries, solar panels, and automotive applications.
- Actuator Valves: DC actuators can offer better speed control and are often used in smaller or precision applications.
Different Voltage Levels Explanation:
A. Low Voltage:
- 12V DC and 24V DC:
- Often used in automotive, solar, and portable applications.
- Lower energy consumption, safer to work with, but may require larger conductors to deliver the desired amount of power.
- 24V AC:
- Common in HVAC systems and industrial control circuits.
B. Standard Voltage:
- 110V AC and 230V AC:
- These are standard mains voltages in different regions (110V typically in the US and 230V in Europe and many other regions).
- Suitable for powering household appliances, industrial machines, and actuator valves in a wide range of applications.
Key Takeaways:
- The choice between AC and DC and the specific voltage level will depend on your application, the existing electrical infrastructure, and the specifications of the actuator valve you are considering.
- It’s essential to match the voltage and current type of the actuator valve with the power supply to ensure proper operation and safety.
- Consulting with electrical engineers or the actuator valve manufacturer can provide valuable insights into the best choice for your particular needs.
By understanding the implications of AC and DC and the different voltage levels, you can make an informed decision when selecting an actuator valve for your application.
What’s the modulating actuator?
Modulating or proportional control valves offer a more sophisticated level of control compared to their on/off counterparts. These valves allow continuous adjustment of the flow rate, pressure, or temperature within a system. This is achieved by precisely positioning the valve’s modulating element, be it a ball, disc, or butterfly, in response to a control signal. Here’s an in-depth look into modulating control valves:
Principle of Operation:
- Signal Processing: Modulating valves operate based on a continuous signal, often provided by a control system or a sensor within the pipeline. This signal is proportional to the desired parameter – flow, pressure, or temperature.
- Precise Positioning: In response to this signal, the valve incrementally adjusts to achieve the desired control. The degree of openness of the valve is directly proportional to the control signal it receives.
Advantages of Modulating Control Valves:
- Fine Control: They provide fine control over the system parameters, ensuring it operates within the desired set points.
- Energy Efficiency: By precisely matching the flow or pressure to the system’s demand, modulating valves help save energy.
- Enhanced System Performance: They help maintain a stable process, enhancing system performance and product quality.
Applications of Modulating Control Valves:
- HVAC Systems: In heating, ventilation, and air conditioning systems, modulating valves control the temperature and flow of water or steam.
- Industrial Processing: They are crucial in various processes requiring precise control of fluids or gases.
- Water Treatment: They regulate the flow of water and chemicals during treatment.
Types of Modulating Control Valves:
- Globe Valves: These are popular for their good throttling capabilities.
- Ball Valves: With a special control disc, they provide excellent modulating control.
- Butterfly Valves: They are used for larger flow rates when compactness and cost are considered.
Actuation and Control:
- Electric Actuators: These actuators receive an electronic control signal (like 4-20 mA or 0-10 V) and move the valve to the required position.
- Pneumatic Actuators: They use air pressure to control the valve position and usually require a positioner to translate the control signal to actuator movement.
Key Considerations in Selecting Modulating Valves:
- Valve Sizing: Proper valve sizing is crucial for achieving accurate control.
- Control Signal Type: Understanding the control signal type and ensuring compatibility with the control system is vital.
- Materials and Specifications: The materials should be chosen based on the application’s fluid, pressure, and temperature requirements.
Modulating control valves is indispensable in many modern industrial and commercial systems, helping to achieve precise control and operational efficiency. By understanding their functionality and ensuring proper selection and installation, you can ensure your system operates smoothly and efficiently.
Troubleshoot & Maintenance of AC/DC Actuator Valve
We should never operate a valve in a live system or under pressure. Disconnection of supply voltage before any maintenance is a must. Before maintaining, it is safe to remove electrical equipment from a hazardous area. Following problems & challenges happen in real life:
The actuator is not operating:
· Thermal Overload protection may be active. Need to reduce operating frequency.
· For incorrect or loose connection of capacitor. One needs to check the circuit diagram & make it correct.
· Wires & switches may disconnect or be lost. We should Inspect and re-connect wires & switches.
· The motor may be damaged. We need to check the supply voltage. If needed, we should replace the motor.
· Low ambient temperature. Mounting a thermostat or heater is a good solution for this.
· The control panel & optional components are loose in connection. We should check the attachment according to the diagram & circuit.
The power is ON, but the motor is not working:
Simultaneous power supply to both sides of the motor. One needs to check the wiring & make it corrected if necessary.
The same parallel source provides power to more than one actuator. Using isolating relays is the best solution.
The capacitor may fail. Replacement is a must.
An output shaft of the motor is not working:
· Improper arrangement of manual override. Manual Override engagement should be automatic.
The actuator turns in one direction only:
The terminal wire connection may be loose or disconnected. You should check the wiring & make corrections.
It turns in one direction when the motor wire connection is loose or disconnected. One needs to match the wiring & make corrections.
Control panel failure. Need proper inspection & rewiring of the control panel components.
24-volt DC Motor Polarity is not switching
External switching/relay needs to be installed.
The actuator turns in the wrong direction:
Incorrect wiring of motor or limit switches. Need proper inspection and reconnection.
The model of the actuator is unidirectional, or it might be wired for unidirectional operation. We should follow the wiring diagram guidelines.
The actuator stops at an unwanted position:
· Limit switch may fail. Need replacement.
· Limit switches may be wired in opposite operations. If this happens, we should do a proper inspection & rewire.
Actuator handle oscillates:
· Small use of lubrication. It may obstruct the valve body. We need to lubricate the valve.
The water inside the valve actuator:
· The seal may be damaged. Greasing the seals is necessary.
Applications of the 24-volt Actuator valve
· Pool and Spa Combinations
· Water Features
· Solar Heating and Cooling
· Wastewater treatment plants
· Power plants
· Refineries
· Mining and nuclear processes
· Food factories
· Pipelines
Pros & Cons of 24-volt DC Actuator Valve
• Electric power is easy to manage and available to industries & factories. A 24-volt actuator valve is cheaper. It is safer to use also.
• Electric actuator provides positioning accuracy for controlling valve functions.
• The actuator valve reduces wiring costs.
• These actuators can provide high output thrust and torque values.
• Electric actuator valves have complex and sensitive modules.
Actuator valves are electromechanical devices that are helpful in remote control. Electric valve actuators provide a more energy-efficient and quiet method of valve control. These actuators are capable of swift operation.