Is A Solenoid Right For Me?

As technology improves the advantages of using a solenoid over the typical motorized valves does increase in both homeowner usages and industrial uses for compressed air and liquid. Whether you are trying to open, shut off, split, mix, or move air, oils, gasolines, water supply, coffee makers, etc. the applications are endless.

There are a lot of advantages to using solenoids such as their speed and combination with automation equipment for streamlining processes is exceptionally effective. This is due to solenoid valves being able to automatically open and close by electromagnetic signals allowing automation processes to be controlled easier and more efficiently.

When you compare solenoid valves to other mechanical valves, often, solenoids will have a lower cost and can have a longer life cycle. They are also able to be rebuilt numerous times over, allowing the user to maximize the lifespan of the valve. Manufacturers often have replacement coils and rebuild kits that allow even a novice home user to do rudimentary maintenance to maximize the valve’s life and efficiency. Often these replacement parts are inexpensive.

Solenoids can often be found in small and simple shapes that are designed to be installed in various locales and various positions depending upon the manufacturer’s instructions. They can also be found in numerous different materials that are suitable for almost any type of environment, temperature, division and class.

The fast response time is also ideal for many applications. Generally, solenoids will respond in less than one (1) second. Making them ideal in many health industries as well.

There are also manufacturers that make it easier to adjust voltages for their solenoid by simply replacing the coil with the correct voltage. This will allow a user to not have to un-plumb the valve but just re-connect the electric components with the new coil.

With all the advantages, often solenoids can appear to be the best valve for the job. But you will want to take into consideration the manufacturer’s tech specs and it is also always important to double check with the distributor or manufacturer of the valve to ensure that it is the best valve for your application.

When considering a solenoid valve for your application it is important to remember to discuss with your distributor or manufacturer how you intend to use the valve. They are an amazing resource to have. And some great things to discuss with them that can affect your application are:

Continuous energization – Not every solenoid valve can be energized 24/7 without understanding that you may need to have replacement coils on hand. It is important to go over the limitations of the solenoid and if it was designed to be on for long periods of time or if a motorized ball valve is better for you.
Depending on the manufacturer, a coil can generate quite a bit of heat. So, it is important to take this into account in the location of where you intend to install the valve. Some valves may require sufficient airflow, where others may not need it. However, the more extras you require the higher the price of the valve.
Not all solenoids are bi-directional flow. So, it is important that if you have backpressure in your application that you discuss whether the valve can handle it or not – and always install the valve in the appropriate flow direction as indicated on the body of the valve.
Always check the outdoor rating for the valve if you intend to install it where it will be exposed to the elements. Not all solenoids are outdoor rated, and many require some type of small covering to help protect against weather extremes.

Solenoid Valve Uses

There are well over 1001 solenoid valve uses. Often, where there are large pieces of machinery, within that machinery, you will find solenoids and solenoid valves. However, their uses expand past that and can be used even creatively. But, if there is a media that is flowing through and needs to be controlled quickly, generally there is a solenoid somewhere in use there.

Did you know that you can find solenoid valves in rocket ships? As we expand our technology, parts like solenoid valves also improve drastically. If you are building rockets (not the model type) you can easily get a piloted solenoid poppet valve that can handle 3000PSI. These are used for rocket propulsion. But, solenoid valves have been used in the rocket industry over seven decades. As the government has declassified secret and top secret documents, many of the old schematics and papers are being published that show the usage of valves in early rocketry science. If you are interested in seeing an example of those documents here is a link. It is quite fascinating.

If you aren’t into rocket science but are looking for more conventional uses of solenoid valves then another common option are pressure washer systems. Many pressure washer systems have been compatible with valves such as the 1/4″ brass solenoid valve. An important note for choosing the best valve will be a chemical compatibility check. There are quite a number of online resources to independently verify all aspects of the valve will be compatible on a chemical level with your chosen media.

You will also find multiple solenoids and solenoid valves in vehicles. If you are familiar with the mechanics of a vehicle then you may find yourself familiar with a solenoid starter. While this is not a valve, the mechanics of the solenoid still operate similarly in the sense of when the solenoid is engaged it is going to close on a pair of heavy contacts and in turn send an electrical current through into the starter motor.

To further expand on solenoids and solenoid valves in a vehicle, you will also find the use of them in multi-tanked trucks and as anti-theft. Operators and consumers are opting to install solenoid valves in their vehicles as anti-theft devices in open SUV’s such as Wranglers. Some have installed the valves as an extra level of protection, especially in older models, where they have installed them and without flipping a switch manually it will not allow the vehicle to receive gas. Or, on an alternative spectrum, those who have installed additional gas tanks in their vehicle have found the solenoid valves very useful to help regulate and choose which tank they are fueling their car or truck from.

While we are on the topic of transportation, you will find solenoid valves throughout railway industries as well. Trains and railway vehicles rely heavily on solenoid valves. This is because of the usage of solenoid valves in their braking systems. This directly affects the safety of the railway vehicle itself. You can also find the infamous train horn is made through a solenoid air valve and some are just like the one linked earlier for pressure washers.

Solenoid valves are also present in the food and beverage industry. If you are making your own beer or wine many of the machines do require solenoid valves to operate. You will also find them in the equipment for dispensing of beverages. And to further expand in the food industry, ice machines, dishwashers, etc. can feature solenoids or have solenoids added onto them. There are consumers out there that install solenoids on their dishwashers for emergency shut offs. Or, there are others that automatic their coffee stations and utilize them for refilling of their coffee machinery.

With today’s technological advancements, easy access to how-to guides and videos online, and creative tinkerers, the possibilities are endless.

Types of Solenoid Valves

There are quite a number of different types of valves out there and the list can become rather daunting once you expand on solenoid valves. However, with solenoid valves we’ve simplified this for the primary types of valves that are out there as well as a brief overview of their functionality and how they operate.

Bi-Stable Solenoid Valve

A bi-stable solenoid valve is also known as latching solenoid valves. This type of valve takes the electrical current pulse to maintain a set position. This means once you’ve sent that electrical pulse the valve will retain the last position until such time when you send a pulse to switch positions. These valves are powered by magnets rather than a spring.

Direct Acting Solenoid Valve

Diagram of direct acting valve open vs closed

Image source – Montgomery County, MD

Direct acting solenoid valves do not use a diaphragm. They do come in normally open and normally close.

For a normally closed version, when there is no power the plunger will block the orifice with the valve seal and a spring is forcing this closed position. When you apply power, it will create an electromagnetic field which will then allow the plunger to lift up and open the valve’s ports to allow media to flow.

The normally open version works just like this but the mechanics are just opposite. Generally, direct acting valves are used for low flow rates.

Indirect Acting Solenoid Valve

Indirect acting solenoid valves are also known as pilot operated or servo operated valves. These valves use the pressure differential of the media to open/close itself. They will require a minimum pressure differential of 0.5 bar.

For normally closed indirect acting valves, the ports are separated by the diaphragm. The diaphragm, also known as a rubber membrane, features a small hole so that the media can flow through the membrane to the upper chamber from the inlet port. When the indirect acting valve is normally closed the spring that supports from above the diaphragm is used so that the valve remains closed. The chamber that is above the diaphragm is designed so that there is a connection to a small channel to the low pressure port. This connection is blocked when the valve is closed by both the plunger and the seal. When the valve has energy applied to, then the pilot orifice [which is larger than the hole in the diaphragm] is opened and the pressure above the diaphragm begins to deplete and allow the diaphragm to be raised so that the media can flow in a unidirectional state from port to port.

For normally open versions it will have the same parts and works similarly but in the opposite manner.

Semi-Direct Acting Solenoid Valve

Semi direct acting solenoid valves, also called assisted-lift solenoids, are essentially a combination of direct and indirect acting valves. This combination allows them to work from little to no pressure but still handle a higher flow rate.

While they look quite like the indirect valves and feature a movable diaphragm that has a small orifice hole and pressure chambers, their main difference is that the solenoid’s plunger has been directly connected to the diaphragm. This allows for the plunger to directly lift the diaphragm to open the valve. During this time a second orifice was also opened by the plunger. It’s orifice has a larger diameter than the first one that is located in the diaphragm itself. This allows the pressure in the chamber above the diaphragm to decrease and allows for the diaphragm to be lifted by both the pressure difference and the plunger itself.

3-Way Direct Acting Valve

The 3-way direct acting valve features 3 ports that are able to do mixing or diverting. You can also find the 3-way direct acting valves with a feature called universal circuit function, this allows the valves to work in both directions. However, only two ports will be connected in each state.

3-Way Normally Open/Closed Solenoid Valves

When a 3-way valve is normally open it will feature 3 ports: cavity, body orifice, and stop port. Beyond the three ports there will be 2 orifices: the stop orifice and the body orifice. Between those two orifices one will always be open and that will allow for 2 flow paths. When there is no energy going to the valve, the plunger will be raised which in turn will seal off the stop orifice and allow for the body orifice to open and media to flow through the valve from the body orifice port and through to the cavity port. When there is energy to the coil then the plunger will be lowered and allowing for the body orifice to be sealed and opening up the stop orifice for the media to flow through the valve from the cavity port and out the stop port.

The 3-way normally closed solenoid valve will work with the same just with opposite mechanisms.

3-Way Directional Control Solenoid Valves

3-Way directional control solenoid valves feature 3 ports: cavity, body orifice, and a stop port. The valve also features 2 orifices which are the body and stop orifice. One of these two orifices will always be open and thus allows for 2 flow paths. When you energize the valve it will either raise or lower the plunger. When you raise the plunger it will seal the stop orifice and open the body orifice which will allow media to flow through the body of the valve. However, when the plunger is down it will seal off the body orifice and open the stop orifice to direct the media through.

Depending on your project, you might need one type of valve or another to satisfy your solenoid valve uses. Use some creativity to figure out the best use, or reach out to us for some guidance.

What Is A Solenoid Valve?

Simply speaking a solenoid valve is a type of valve that is able to be controlled electronically. While you can have dozens of types of valves, specifically a solenoid valve is a valve that has a solenoid used to open and close the flow of media.

A solenoid is an electric coil with a moveable plunger at its core. The default rest position will either close off the valve’s orifice or allow it to be open. This will depend on if your valve is normally open or normally closed.

When you energize the valve, an electric current runs through the coil and creates a magnetic field concentrated in that area. This magnetic field allows the valve to move the plunger up and down which will then allow for the opening or closing the orifice.

There are different types of solenoid valves, as previously mentioned. There is a distinctive difference between externally piloted, direct-acting valves, and internally piloted valves. You can also expand on the differences of the valves based on the number of port connections:

if it modulates
the number of flow paths
the valve’s technical details itself

You can go further into differences based on the valve’s distinctive characteristics and what your job requires.

Such as valves can have a manual override function, handle LPG, work in a vacuum, handle back pressure, etc. A valve can be as unique as the project it is being installed into.

Valves can have many ports for fluid or gas paths. For example, a 2-way valve will have 2 ports and when the valve is open the ports are now connected and allow fluid or gas to flow between the ports. However, when the valve is closed then the two ports are no longer connected and the media flowing through the valve will stop.

Some valves come where their default state is open, known as normally open valves. When you have a valve like this it means the ports are connected when there is no energy and that once you apply energy to the valve the ports will then become isolated from one another until such time energy is removed.

The opposite of normally open is a normally closed valve. Those will be closed until power is applied and will then allow the valve to open connecting the two ports.

From there you can get into 3-way valves and other more intricate styles. 3-way solenoid valves are ones that feature 3 ports and the solenoid typically has one port that will connect to one of the other two ports which are generally a supply port and then an exhaust port.

While there are many ways to use a solenoid including one that acts directly on the main valve, you can also use a solenoid valve to actuate a larger valve. Those are solenoids that are combined with a pneumatically actuated valve. Often these are sold and packaged as a singular unit and referred to as a solenoid valve.

Pilot valves do not require as much power to control, but they are significantly slower. The other thing with pilot valves is that they generally will require full power at all times to open and stay open. However, direct acting valves often only need full power to open the valve and then the power consumption does reduce to maintain the valve’s open position.

Here is a great explainer video on how solenoid valves work…

What Is A Solenoid?

What exactly is a solenoid and how do they work? That’s a really good question to ask yourself while learning more about a seemingly simple device that we use every day without realizing it.

A solenoid is a common term for a coil of wire that is used as an electromagnet. The term can also encompass not just the wire but also the housing and a moveable plunger. But, the coil of wire is that of a corkscrew shape which is then wrapped around a piston.

When you introduce electricity, you will have a magnetic field that forms around the coil which will allow the plunger to be drawn in. The plunger, or armature, is moveable and as voltage is passing through the coils, the armature moves to increase the total flux linkage by closing the air gap between the two cores. The armature, which is spring-loaded, is able to retract back to its original position once any electrical current has been removed. Essentially, a solenoid takes the electrical energy and transforms it into a mechanical function.

The housing that covers the coil allows for a concentration of the magnetic field that is generated by the coil. As with all magnets, the magnetic field of a solenoid that has been activated does have positive and negative poles. Those poles will allow for material to be attracted to or repelled from the magnetic field. In the case of a solenoid, this magnetic field will allow for the piston to move either backwards or forwards, often in under a second.

The quick response of a solenoid allows them to be used across a wide variety of industries from motor vehicles, door bells, ventilators, pinball machines, and so much more. For example if you are using solenoids in a motor vehicle, besides using them for fuel you can also find them in the ignition system. The electrical current when a car’s ignition system has been powered on will pull contacts and allow the circuit to close between the vehicle’s battery and the starter motor.

You can also find solenoids attached to valves that are installed and wired into alarm systems allowing people to power their alarm and shut the water off to vacation homes preventing water damage. Their uses are quite frankly, endless. Besides being found in vehicles and homes, you can find them in door bells, paintball guns, large machinery, pressure washers, and more.