How to Test a 24V DC Solenoid Valve, Good or Bad?

The solenoid valve quality, good or bad, is decided by the coil and the valve. Therefore, it mainly take a test on this two parts to check if the solenoid valve is good or bad.

This is a 24V DC solenoid valve and how can we know it is good or bad? Let us make a test for it.

First of all, find a 24V power source, and connect it to the coil. If any noise is heard, it means the solenoid valve coil and valve element are normal, which can ensure normal connection.

Then, leakage detection is conducted. It is the best if there is the air supply, for the air supply can be directed injected to judge whether gas leakage exists. If there is no air supply, block the air outlet and blow it using the mouth.

Testing the coil of solenoid valve can also be conducted with the multimeter.

1. Power on the solenoid valve, take off the connector plug, and use the multimeter to test whether there is power or not.
2. Power on the solenoid valve and move the thin steel wire close to the coil to see whether its suction is viable.
3. Repeat testing of the solenoid valve power on and off. Use a thin internal hexagonal wrench to poke at the brass “small pits” on the solenoid valve axial, to see whether absorption-ejection is normal.

The specific method to detect the solenoid valve quality is as follows. And there is also the detection methods for some common faults of solenoid valve.

Get the solenoid valve connected with the medium (the liquid or air with the pressure, and the voltage value is the intermediate value of the solenoid valve voltage scope). Get the solenoid valve coil with power. If the medium changes from power-on to power-off or from power-off to power-on, it means the solenoid valve is good. Otherwise, the solenoid valve has problems.

Solenoid valve coil short circuit or open circuit

First, use the multimeter to measure its on/off status. When the value of resistance is close to zero or is infinitely large, it is an indication of coil short circuit or open circuit. In contrast, if the value of resistance is normal (around dozens of ohm), it cannot yet prove that the coil is in a good status. To ensure reliability and accuracy of your test results, please carry out the following final test. Find a small screwdriver and place it nearby the metal pole in the solenoid valve coil. Then, power on the solenoid valve. If magnetism is perceived, it means the solenoid valve coil is good. Otherwise, the valve coil has been damaged. A method to cope with the above problem is to change for a new solenoid valve coil.

Solenoid valve core

Fault 1: When the medium voltage of the solenoid valve is normal, press on the red manual button of the solenoid valve. If the solenoid valve shows no response (the voltage medium shows no on/off changes), it means the valve element has been damaged.

A method to cope with the situation is to check whether there are problems with the medium, such as whether there is too much water in the compressed air (sometimes, the oil-water separator does not work well, particularly when the pipeline design is not reasonably designed, there will be too much ponding in the compressed air pumped into the solenoid valve), and whether there are too many impurities in the liquid medium. If these problems exists, the ponding or impurities in the solenoid valve and pipeline should be eliminated. If this method does not work yet, please repair or exchange the valve element, or directly change the whole solenoid valve for a new one.

Fault 2: If the coil is found to be the original coil and the magnetism is normal when the coil is electrified, but the solenoid valve still does not move (at the moment, the function of the magnetic valve' s manual button might be normal), it suggests that the valve element has been damaged.

A method to cope with the above problem is to repair or change the valve element, or directly change the whole solenoid valve for a new one.