We appreciate that you search for an air compressor switch, to be specific, an air compressor pressure switch, as you might already be aware of the safety precaution and prepare yourself.
Even when you do not have a good knowledge of how the switch works and how to choose the suitable one, you still land in the right place.
In this blog, we will give a brief and useful explanation about the air compressor switch, as well as the top recommendations in the market.
Check them all out!
Air Compressor Switch Reviews: A List of 3
1. Ingersoll Rand 23474653 for Single Stage Compressor
The good news is, Ingersoll Rand does not only manufacture the air compressor, but also the supportive switch to enhance the performance and long span of their machine.
Take the Ingersoll Rand 23474653, for instance.
This device is designed for single-stage air compressors at around 175 PSIG cut-out pressure and 135 PSIG cut-in pressure, using an on-the-shelf unloader valve and NEMA type-1 enclosure.
Besides the recommended 5HP single-phase compressors by Ingersoll Rand, the switch also supports other similar models, such as the TS4 or 2340.
In practical terms, the pressure is blown off through the valve into the discharge pipe. As a result, you can easily spot the amount of air fluctuating in the tank. Also, the switch works to maintain a safe level of pressure.
In drawback, the PSI capacity is limited – only from 2 to 6 PSIG at a full turn. Thus, it is only powerful enough for small shops, DIY tasks, or overall domestic purposes.
- Versatile for various models of air compressor
- A large tank gauge to minimize the regular exchange
- Streamlined air pressure through the unloader valve
- Easy to install and operate
- Limited PSI
- Non-adjustable switch
2. Square D by Schneider Electric FHG12J55XCP
You might be surprised knowing that the Square D by Schneider Electric Compressor Switch has been introduced for more than 67 years and still be popular.
It is thanks to its rugged and reliable performance for jet and reciprocating systems, such as the air compressor.
Accordingly, the switch features the patented Pumptrol (™) technology and a two-way pressure release valve to ensure safe operation. Upon the reduction in pressure or water, the pump is supposed to be cut off. Next, you should move the lever and wait for the pressure build-up so that the contacts are closed. Then, the compressor will be back to the normal work.
With such a straightforward logic, this Square D by Schneider Electric Compressor Switch supports a simple installation and ease of adjustment.
Our complaint is related to the small capacity, making this switch is limited to small compressors and devices such as the pumping air or dental services. Particularly, the contacts are only 10 AMP and the switch works perfectly on 2HP compressor (230V AC.)
Moreover, you must be careful with the chemicals (lead and compounds) inside the switch. They can result in reproductive harm.
- Years of experience
- Rugged performance for domestic use
- Easy to install, operate, and adjust
- Only for small projects and tasks
- Possibly harmful chemicals
3. Lefoo New H/D Pressure switch CC7UL1
The Lefoo New H/D Pressure switch 95-125 w/Unloader CC7UL1 is the last on the list but by no way, the least interesting one.
In contrast, this small device features an impressive performance in its affordable category.
For your information, this pressure switch adopts the single port, along with an unloader lever. It means the machine is more effortless to use than the two-port ones. The pressure will enter directly to the port and access the internal diaphragm and the contacts will, in return, break or make the circuit.
In addition, all the parts, including the unloader, are interchangeable for easy installation and replacement. You do not need to have any screws stripped out in this air compressor switch.
Just a small fault in design that we want the manufacturer to improve. Instead of the unloader hookup which causes the handle to be knocked sometimes, the unloader tube should be horizontal.
- Easy to installation
- Straightforward single-port switch
- Inconvenient unloader hookup
- Plastic-like appearance
What Is An Air Compressor Pressure Switch?
This small device is what you are looking for.
It helps turn on/off the power of the air compressor motor by measuring and controlling the pressure inside the tank when it reaches a specific level.
In that way, the compressor can maintain safe pressure and work smoothly against the dangerous ruptures.
Main Parts Explanation
At a glance, the air compressor switch is just about the size of our palm and with the shape of a rectangular housing.
In detail, it features several key components to perform multiple “auto” functions to help control the operation of your air compressor, as follows.
- The Knob, so-called Auto/Off Lever, allows separating the contacts manually. You should always turn the knob off before you plug or unplug the machine.
- The Contacts are in place to control the electrical circuit. Specifically, when being separated by the lever, they restrict the power to the motor. These parts are crafted mainly with silver and nickel.
- The Terminals will connect between the input/output power leads and the switch to run the motor.
- The Adjustment Spring, as the name suggests, helps with adjusting the cut-in and cut-out pressures. Based on specific uses, there might be one or two springs.
- The Pressure Relief Valve will relieve pressure within the check valve and the pump via the actuation of the lever after the contacts are separated.
- The Diaphragm pushes against and forces the contacts to be separated when the air pressure reaches the “cut-out” level. At that time, the motor of the air compressor will shut down.
How does an Air Compressor Switch Work?
Let’s picture how all of these components work together!
First off, you have to unplug the compressor and remove all the valves between the storage tank and the switch.
Then, connect the compressor with a proper rated switch and plug the machine so that air can flow freely between the tank and the switch.
When the power is ready, you often move the knob to the “auto” position and the contacts are forced together to start the motor. Consequently, the compressor begins to pressurize.
To the point of “cut-out” pressor, the diaphragm pushes against the power mechanism to separate the contacts. As a result, the circuit is broken and the motor will stop.
Meanwhile, the relief valve opens to use up the air trapped within the check valve and pump. The pressure in the storage tank is decreased to the “cut-in” settings. Then, the contacts close and restart the motor.
FAQs About Air Compressor Switches
1. What are Cut-in Pressure and Cut-out Pressure?
Simply put, the compressor should turn off when the pressure reaches the cut-out point and restart when the pressure decreases to the cut-in point. The cut-in pressure, hence, is never higher than the cut-out one.
It is the best practice that you set the pressure difference between these two points at least 14 PSI. Otherwise, the compressor might start and stop repeatedly over a short time. Also, you must always set the cut-in point first, the cut-out point goes second.
2. When Should I Exchange the Pressure Switch?
Here are some hints for replacement of the air compressor switches:
- The machine turns off even before reaching the cut-out point
- The compressor does not be back to work at all
- The compressor goes on and off repeatedly in a short cycle
- The contacts, diaphragm, and other components do not change their positions as supposed
3. How to Replace the Pressure Switch?
Keep safety in mind.
Firstly, you should check these parts carefully:
- Check requirement of electrical load to ensure the new switch is compatible with motor currents
- Figure out the rated pressure maximums of the compressors. Then, never set pressure settings higher than what your machine can handle
- Make sure the new switch located on the current pressure switch
- Invest in additional connectors such as adapters, if needed
Then, follow these steps to replace the new switch:
- Unplug the compressor
- Depressurize the tank by opening the valve at the bottom
- Locate the unloader pressure valve and remove the line, if any
- Get rid of top gauge, pressure regulator, and quick-connect fitting from the switch. Disconnect the wires as well
- Remove the old pressure switch and install the new one. Secure the switch with a wrench.
- Reassemble the valves and plumbing parts.
You complete the task, then!
Always check out the machine first before looking for an air compressor switch. It is recommended for small or domestic compressors. Meanwhile, the large industrial compressors usually come with the auto-controlling system themselves.
Try to understand how all the components work to ensure proper settings and maintenance for the switch and the air compressor. More importantly, this helps guarantee your safety during the installation and operation of this device.
Thus, digest this blog thoroughly. We hope it is helpful!