Pneumatic control valve
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How many wires does a pneumatic control valve have? ? DCS-controlled, with feedback
2 pairs. . . . . . . . . .
This post was last edited by crjgood on 2014-5-22 at 14:08. There are two pairs of responses. One AO signal, outputs a control signal ； An AI signal, feedback on valve position
What was said on the 3rd floor is incorrect. Pneumatic control valves are not on-off valves; they require a two-core signal output wire, as well as a two-core (4–20 mA) or three-core (potentiometer) valve position feedback wire.
It should be 2 pieces. A two-core wire, used for AI input ； If it is a DO output, it should be 4-core or 3-core for the feedback DO signal; if it is a feedback AO signal, then one 2-core wire is sufficient
Pneumatic control valves generally have two pairs of wires: one pair (two wires) serves as the DCS control signal output wires, that is, the signals sent from the control room to the field equipment； One pair is the feedback signal wires, also two in number; both of these pairs are connected to the valve positioner. However, our factory only connects the output signal wires; most of the feedback signal wires are not connected.
For FF, just two wires are sufficient – for both control and feedback
All I’ve seen are two-wire systems. I saw someone upstairs say that the feedback signal has three or four wires; please have the relevant personnel confirm this.
All I’ve seen are two-wire systems. I saw someone upstairs say that the feedback signal has three or four wires; please have the relevant personnel confirm this.
The feedback is for 4-core wires: 1 pair is in the on state, and 1 pair is in the off state
Usually there are two wires, transmitting signals of 4 to 20 milliamps; there are also four-wire versions, with one used and one as a backup.