The solenoid valve has two parts, the solenoid coil and the magnetic core, and is a valve body containing one or more holes. When the coil in the solenoid valve is energized or de-energized, the operation of the magnetic core will cause the fluid to pass through the valve body or be cut off to change the direction of the fluid. Because the current is to pass through the coil, the solenoid valve coil may be burned out. One of the most important reasons - spool stuck.

The first is how to detect whether the electromagnetic coil is good or bad

Use a multimeter to measure the resistance of the solenoid valve, the resistance of the coil should be around 100 ohms! If the resistance of the coil is infinite, it means that it is broken. You can also energize the solenoid valve coil and put iron products on the solenoid valve, because the solenoid valve has magnetic properties to attract iron products after the solenoid valve coil is energized. If it can absorb iron products, it means that the coil is good, otherwise it means that the coil is broken. The detection method for the short circuit or open circuit of the solenoid valve coil is to measure its on and off with a multimeter first. If the resistance value approaches zero or infinity, it means that the coil is short circuited or open circuited. If the measured resistance value is normal, it does not mean that the coil must be good. You should also find a small screwdriver and put it near the metal rod passing through the solenoid valve coil, and then energize the solenoid valve. If it feels magnetic, then the solenoid valve The valve coil is good, otherwise it is bad.

There are also two factors for spool jamming, external and internal

1. External reasons

Whether the solenoid valve can maintain long-term stable operation has a lot to do with the cleanliness of the fluid medium. An example may be more clear. Compared with the solenoid valve working in pure water and other media, pure water itself contains only a small amount of particles and minerals, and the solenoid valve will only have a small amount of impurities attached to the valve core after a long time of work. superior. However, there are many particles and impurities in other liquid media. These fine substances will slowly adhere to the valve core and gradually harden. It is easy to generate a large amount of deposition at the valve core of the solenoid valve, thus affecting the normal operation of the valve core. That is to say, the phenomenon of spool jamming is caused.

   When the valve core is stuck, the current value in the solenoid valve coil will increase several times, and some coils that have not been specially treated are easily burned out.

2. Internal reasons

The core components inside the solenoid valve mainly include the valve core and the slide valve sleeve. The gap between these two core components is generally very small. When impurities are mixed in or the degree of lubrication is not enough, the two are easily stuck to each other. The emergency treatment method for this problem is to use tools such as iron wire to insert through the small hole in the head of the solenoid valve, so that the valve core can rebound and resume operation.

   But if you want to completely solve the stuck problem between the valve core and the slide valve sleeve, you need to disassemble the solenoid valve, take out the valve core and slide valve sleeve, clean them with a special cleaner and reassemble them. Finally, check whether the oil spray hole of the lubricator is blocked and whether the amount of lubricating oil is insufficient. After all the internal problems are solved, the operation of the spool in the slide valve sleeve will not be easily blocked and stuck.

   If the solenoid valve coil is burnt out, the wiring of the solenoid valve can be removed and measured with a multimeter. If the circuit is open, the solenoid valve coil is burned out. The reason is that the coil be affected with damp, which will cause poor insulation and magnetic flux leakage, which will cause excessive current in the coil and be burned down. Therefore, rainwater should be prevented from entering the solenoid valve. In addition, the spring is too hard, the reaction force is too large, the number of turns of the coil is too small, and the suction force is not enough, which can also cause the coil to burn out. For emergency treatment, the manual button on the coil can be turned from "0" to "1" during normal operation to open the valve.