If you need a valve, you have a handful of choices that can solve various issues differently. Making the correct choice based on your specific needs can save you money and time.
We have found that many of our customers ask about the differences between a motorized ball valve vs. a solenoid valve or choosing one over the other.
This article will explain the difference between the two types of valves and the pros and cons of each.
Why Use a Valve?
If you have to control fluids, air or gases in your system, valves will help. Valves are critical components in everything from simple domestic tools (like sprinkler systems) to massive mechanical systems (including actual rocket ships from NASA and SpaceX). Most people use valves on their garden hoses and don’t even realize it.
Motorized valves take care of unmanned plants. They work just like manual ball valves, but they rely on electric motors to open, close, dose and distribute. Operators can run them from automated systems either in-house or remotely. Knowing the difference between a motorized ball valve and a solenoid valve can make the plant run more efficiently by choosing the best valve for your situation.
What Is a Solenoid Valve?
A solenoid valve works with an electric current. A solenoid is a wire coil that acts as an electromagnet, and in a valve system, the solenoid controls the current through the valve. In its resting state, a (normally closed*) solenoid valve is closed with a plunger blocking the opening. To open the valve, a simple electric current runs through the solenoid and creates a magnetic field. This magnetic field lifts the plunger and opens the valve.
*The reverse of this would be a normally open valve that remains open until the valve is shut by an electric current.
Manufacturers use solenoids to control fluids, air and gases because the valves can distribute, release, or mix elements with pinpoint control. Since solenoid valves work with a variety of substances, businesses use them in several capacities.
Solenoids require little power, and they are reliable, durable, and compact.
What Is a Motorized Ball Valve?
Ball valves use motors to rotate a ball with a hole in the center to control flow. When the hole is in line with the flow, the valve is fully open, and when it is turned perpendicular to the flow, it is closed. Most electric ball valves don’t require power to hold position like solenoid valves. Some electric actuated ball valves can be opened or closed manually.
Ball valves work well in situations that involve large volumes of flow. For example, airports use them for de-icing aircraft, greenhouse managers use them for watering greenhouses, and farmers use them for watering large farms. Buildings with fire suppression technology rely on ball valves for opening and closing the sprinkler heads.
Motorized ball valves allow liquid, gas, or air through electric controls. Some have several valves to manage large systems.
Types of Valves
Choosing between a motorized ball valve vs. a solenoid valve is just the first step. These two types of valves also come in different subtypes. Each can be useful in various situations.
Types of Solenoid Valves
Three common types of solenoid valves do different jobs that require fluid movement:
- Two-way solenoid valve: This type of valve has an inlet and outlet connected to the fluid source. Two-way valves only have the option to open or close. The valve closes to shut off the fluid, and the valve opens to let it flow.
- Three-way solenoid valve: This type of valve has three ports. They have three control settings, normally closed, normally open, and general type. With three-way valves, you can divert flow through the different ports.
- Four-way solenoid valve: This type of valve works as a double-acting cylinder. It will have one or two exhaust ports, two-cylinder ports, a pressure port, and a few connectors.
Types of Motorized Valve
Three types of motorized valves help move fluid through pipelines:
- Quarter-turn motorized valve: This type of valve uses a 90° (quarter-turn) to open and close a port. These actuators rely on ball valves and plugs, chokes, and butterfly valves to open and close to precisely let fluid move.
- Multi-turn motorized valve: These actuators use balls, gates, or other tools to open and close valves with complex needs.
- Linear-motorized valve: A linear valve will work with control or diaphragm valves for fluid movement.
Pros and Cons of Solenoid Valves
Solenoid valves have plenty of benefits and just a few drawbacks. You want to be sure you’re always using the correct type of valve for the proper application.
Solenoids open and close quickly, and you can use them with AC or DC currents. They can be used to almost instantaneously open or close a channel directing the flow of media in the system.
Due to their simple design, the power consumption is rather low for a solenoid valve. Additionally, they require no power to hold their normally open or normally closed position, only needing electricity to change and hold the on position.
However, in order to hold a position, a solenoid valve needs to continuously draw power from its source. This can lead to heat building up within the coils, burning out the valve if left in the on position for too long.
They are an affordable option for many systems that are easy to install and maintain. Unlike the alternative ball valve, a solenoid valve can be rebuilt by replacing the coils or other internal parts that may have worn out.
They have high-cycle capacities, but they have limitations with back pressure and inlet pressure due to different internal configurations in the flow path.
Another downfall of solenoid valves involves pressure differentials that need pilot designs. Solenoids can handle the flow, but if you need more, you'll need to consider using a motorized ball valve instead. Solenoids do not have manual overrides, so users must consider water-hammer potential from rapid closing.
Most solenoid valves work with an internal diaphragm and plunger. This type of mechanism can be subject to issues if there are particles in the line. Any debris will cause the valve from sealing properly allowing it to leak. Most valves can be serviced but this is another area where a ball valve shines. Since they don't seal with a diaphragm they can handle more particulates or the random debris.
Pros and Cons of Motorized Ball Valves
Like their counterparts, motorized ball valves also have pros and cons.
One of the benefits is the valve’s ability to continue working at a high flow rate, despite a pressure drop. Since they don't have a diaphragm they have a greater Cv value, or flow compared to the same size solenoid valve.
They are, like solenoid valves, another affordable valve type that is fairly easy to install. They are easily integrated into automation systems through multiple devices like PCs and even Raspberry Pis. The total operating cost of a motorized ball valve is also lower than solenoid valves because they don't require continuous power to hold position. This feature is also beneficial to users since the ball valve is not prone to burning out like solenoids.
One drawback is that motorized ball valves move slower than solenoids. They operate quickly, but not instantaneously. However, this may be seen as a benefit for some systems prone to the water hammer effect since the liquid or gas does not come to an abrupt and sudden stop.
Another disadvantage of an electric actuated ball valve is the wear and tear that can occur inside the ball valve itself. Suspended particles that may end up transferred through your system can cause wear and tear on the ball itself or cause it to get stuck. While they are more durable against regular wear and tear than a solenoid valve, it is still something to take into consideration.
If there is damage to the internal components, it can become more of an issue to service. The ball in these types of valves are machined with precise measurements to work within the system. Damage to the ball may render the valve useless as it cannot easily be replaced, unlike solenoid valves which can be rebuilt.
In the end, to decide what type of valve to use, you need to understand why you need a valve. If you have further questions or guidance for the correct valves for your project, our valve experts are available by phone or chat on Electricsolenoidvalves.com.