1、 Overview
The DFQ intelligent operator receives input signals of standard current, voltage, and valve position from the DCS system of the front-end regulator, and outputs standard current and voltage signals. The servo amplifier drives the electric regulating valve or the electrical converter and valve positioner drive the pneumatic diaphragm valve. Suitable for use as a backup operation for DCS system loop regulation control output and intelligent regulator control output.
2、 Functional Features
1. When the operator is in automatic working mode, its input and output are equivalent to straight through, and the percentage of valve position opening of the input and output is equal, and the input and output are isolated to achieve automatic control of the valve by the DCS system or regulator
2. When the operator is in manual mode, the output value of the valve position opening can be directly modified through the panel buttons
3. Hand automatic undisturbed switching
4. Remote forced manual
The operator provides a remote forced manual input signal, which only accepts dry contacts. It is usually connected to the DCS regulator of the preceding stage, so that when the preceding stage fails, the operator can automatically switch to manual mode, keeping the valve position unchanged to ensure that the actual valve position is not lost control due to the preceding stage failure
5. Valve position feedback output signal
It is a signal output by the operator to the preceding DCS system or preceding regulator, which has two functions: firstly, to enable the DCS system to monitor the actual valve position at any time; The second is to achieve undisturbed switching and usage of the operator
6. Can set the upper and lower limit amplitude states of valve position opening
7. Dual screen display: The main screen displays the valve position given input signal, and the auxiliary screen displays the valve position opening. In manual mode, the percentage of manual output given by the valve position can be observed through the attached screen
8. Manual automatic status output: relay form
9. Valve position given input signal: standard signals such as 0-10mA, 4-20mA, 1-5V, 0-5V, etc
10. Valve position given output signal: 0-10mA, 4-20mA
11. Valve position feedback input signal: 0-10mA, 4-20mA, 1-5V, 0-5V, 0-1K Ω and other signals
12. Valve position feedback output signal: 0-10mA, 4-20mA
13. Display mode: 4-digit 0.8-inch or 0.56-inch LED display
14. Current output: Require load resistance to be less than 750 Ω
15. Working environment: ambient temperature 0-50 ℃, relative humidity below 85% RH
