EO/EC pneumatic butterfly valve, could someone with more experience give some guidance?
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First of all, it’s not FO and FC; EO/EC is something different from FO/FC. What I’m not quite understanding is the explanation of EO/EC in the diagram below. The valve is configured as a combination of a two-position five-way solenoid valve controlled by a single electrical signal and a double-acting cylinder. As I understand it, EC means closed when powered, while EO means open when powered; there may be other terms as well. The position when power is lost is denoted as EC/EO. Let’s take a look at the diagram: if I choose the EC type, the valve will be closed (1-2-A) when the solenoid is activated ； Conversely, when the solenoid valve loses power, the valve opens (1-4-B). When a power failure occurs, in my opinion the solenoid valve should be in a de-energized state; it should be (1-2-A), but the diagram shows (1-4-B). I really can’t understand this, unless the solenoid valve remains energized during a power failure. Could you please help me understand this?
Based on the diagram and instructions you provided, if the EC type is selected, the valve is closed when the solenoid valve is activated (1-2-A), and the valve opens when the solenoid valve loses power (1-4-B), which is consistent with your understanding. When a power failure occurs, the solenoid valve loses its power supply and is therefore unable to maintain its original state; as a result, the valve stays in the middle position. In other words, in the event of a power failure, the valve will remain in its current state, whether open or closed. Therefore, in this case, (1-4-B) shown in the diagram does not represent the condition during a power supply failure. .
Remaining in place is the two-position five-way dual-control type; what I’m referring to is the two-position five-way single-control type
This post was last edited by hanhaigang128 on 2023-7-17 at 17:40. EC means that the pneumatic butterfly valve closes when the solenoid valve loses power, while EO means that the pneumatic butterfly valve opens in that situation. Both EC and EO describe the state of the pneumatic valve when there is a power loss; whether the valve is in the EC or EO state depends on whether terminals 2 and 4 of the solenoid valve are connected to cylinders A and B, respectively, or whether they are connected to cylinders B and A, respectively. Your diagram shows this clearly.