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The pressure switch is your compressor’s control center. It regulates the compressor’s cycles and helps prevent overpressurization. Of course, correctly wiring a pressure switch air compressor is a crucial process. It ensures that your compressor and other components work safely and efficiently.
Common Air Compressor Pressure Switch Wiring Mistakes
To help you better understand the wiring process, here are four common mistakes seen in air compressor pressure switch wiring:
- Direct motor wiring: A problem one may often see is wiring directly to the compressor motor, bypassing the pressure switch. This bypass disrupts the switch’s control over the motor, resulting in it continuously running regardless of the system’s pressure. In this case, it could lead to overpressurization and activate the safety valve.
- Incorrect connections: Another frequent error is mistakenly connecting wires to the motor contacts instead of the line contacts on the pressure switch. This misconfiguration prevents the switch from effectively controlling the motor. As such, it can cause the compressor to run continuously and risk the system overloading.
- Misunderstanding contacts: Confusing the different contacts’ purposes can lead to wiring errors. When one incorrectly uses the motor contacts for power input rather than the line contacts, it can disrupt the switch’s ability to regulate the air compressor. You can guess what happens then — the compressor continuously runs regardless of the system’s pressure.
- Faulty pressure switch configuration: Improperly configuring the pressure switch can lead to erratic compressor behavior. For example, setting incorrect pressure cutoff levels or failing to adjust the differential pressure settings. As a result, this may cause the compressor to start and stop excessively or fail to maintain adequate system pressure.
Wiring a Pressure Switch for an Air Compressor
We laid out a few easy-to-follow instructions to help you wire a pressure switch. But before you start, there are a few materials you’ll need:
- Pressure switch
- Electrical wires with a suitable gauge for the compressor’s power requirement
- Wire cutters or strippers
- Screwdriver
- Electrical tape is optional
- Circuit tester or multimeter for safety checks
Without further ado, here’s our general guide to help you through the wiring process:
- Safety first: Before anything else, switch off the compressor and unplug it from the power source.
- Identify pressure switch terminals: A pressure switch should have clearly marked terminals or contacts. There are at least four — two for power input and two for power output to the motor.
- Understand the wiring diagram: Pressure switches typically come with a wiring diagram. Familiarize yourself with which terminals are used for what. For example, power input is usually marked “L1” and “L2.” And power output is generally marked “T1” and “T2.”
- Connect the power supply: The power supply wires are typically the incoming wires that provide electrical power to the switch. Connect these two wires to the power input terminals on the pressure switch. Tighten the terminal screws to ensure it’s secured in place.
- Connect the motor wires: Find the wires leading to the compressor’s motor. Once identified, connect them to the motor terminals on the pressure switch. Again, tighten the terminal screws for a secure connection.
- Grounding: Some pressure switches have a grounding terminal. If this is the case with yours, connect the ground wire according to the manufacturer’s instructions.
- Check the connections: Double-check all connections to ensure they’re tight and secure. Loose connections may cause issues like electrical hazards.
- Insulation: If desired or the switch’s housing allows, you can use electrical tape to insulate the terminals and wires. Doing this may prevent accidental contact or short circuits.
- Test the setup: Once the wiring is complete, you can plug in the air compressor and turn it on. While the compressor’s running, monitor the pressure switch. Ensure the pressure switch engages and disengages the motor at the appropriate pressure levels.
- Safety check: Use a circuit tester or multimeter to check for any voltage at exposed terminals. Through this safety check, you can ensure that there are no live circuits when the compressor is switched off.
How to Video: Properly Wire Your Air Compressor’s Pressure Switch
If you’re more of a visual learner, then we’ve got you covered. The video below addresses these problems and demonstrates how to wire to a pressure switch for air compressors.
Need Expert Guidance? Contact General Air Products
At General Air Products, we stand by quality in our manufacturing and our commitment to top-tier customer service. Whether you need guidance on selecting the perfect air compressor pressure switch or assistance with installation, our experts are here to help.
Reach out today via our online contact form or call 888-814-2196 if you have any questions.