The Difference Between Electric Valves and Solenoid Valves

An electromagnetic valve is an electromagnet that, when powered, generates a magnetic force to overcome the spring pressure, thereby moving the valve core. It consists of a simple electromagnetic coil, is cost-effective, and can only achieve on/off functionality.

Electromagnetic valves are driven by an electric motor to move the valve rod, thereby actuating the valve core. They are categorized into shut-off valves and regulating valves. Shut-off valves operate in a two-position manner, either fully open or fully closed. Regulating valves are equipped with an electromagnetic valve positioner, which uses closed-loop regulation to dynamically stabilize the valve at a specific position.

Comparison of Applications between Electric Valves and Electromagnetic Valves

Electromagnetic Valve: Used for switching control in liquid and gas pipeline systems, featuring dual Digital Output (DO) control. Typically employed for controlling small pipelines.

Electrical Valves: Used for analog adjustment of fluid, gas, and air system pipeline medium flow, controlled by AI. Electrical valves can also be used for two-position switch control in the control of large valves and air systems.

Electromagnetic Valves: Used exclusively for on/off control, these are DO controlled valves, suitable only for small pipe control, commonly found in DN50 and below.

Electrical Valves: Capable of receiving AI feedback signals, operable via DO or AO control, commonly used in large pipelines and air valves, etc.

1. Switch Configuration:

Electromagnetic valves are driven by coils, capable of only opening or closing, with short action times during switching.

Electromagnetic valves are typically driven by motors, and their on/off actions require a certain amount of time to simulate a variable quantity, allowing for adjustment.

2. Job Nature:

Electromagnetic valves typically have a low flow coefficient and a small pressure difference. For instance, the flow coefficient of a standard 25mm electromagnetic valve is significantly lower than that of a 15mm electric ball valve. The drive of an electromagnetic valve is through an electromagnetic coil, which is relatively easy to be damaged by voltage surges. It functions like a switch, serving only two purposes: on and off.

Electromagnetic valves are typically driven by motors, offering good resistance to voltage surges. They are designed for quick opening and closing, commonly used in low flow and low-pressure applications where high switching frequencies are required. In contrast, electric valves are adjustable for opening degrees, with states including fully open, fully closed, and semi-open, allowing for control of the flow of media within pipelines—a capability that electromagnetic valves do not possess.

Electromagnetic valves can generally reset when power is disconnected, but for electric valves to have this feature, a reset device needs to be added.

3. Applicable Technology:

Electromagnetic valves are suitable for certain special process requirements, such as leakage and special fluid media, and are priced higher.

Electrical valves are generally used for regulation, and some are also used for on/off applications, such as in the terminal of fan coil units.