Central control DCS configuration
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How should a cut-off valve be configured? I want to use a button to control a relay in order to turn the valve on and off – pressing the button turns it on, and pressing it again turns it off. I’m just starting out; please give me some guidance.
Do you mean Zhejiang Zhongkong’s DCS by ‘central control’ here? When asking questions, avoid being vague; the more detailed, the better
For the JXP300 control unit, this button operates in a momentary manner and can only be used to start or stop the pump – pressing it turns it on, and then it returns to off state. To have it turn on with one press and off with another press, a bistable switch is required.
Why don’t you try stacking the original two buttons on top of each other and setting them to be hidden? For example, the on button is at the top and the off button is at the bottom; the on button displays “off” while the off button displays “on”. The on button is hidden when it’s in the on state, and the off button is hidden when it’s in the off state. When you click, it actually turns on, but the off button is what is displayed; clicking again turns it off, at which point the on button is shown. This process is repeated.
You could use a switch button similar to those used for circuit breakers, but have you considered whether there might be something unreasonable about the way you enable and disable it in this manner? Normally, even the start/stop of a single point output is handled using SRs in the program; the buttons can still be assigned separate addresses to enable point-to-point operation.
Two buttons are needed to complete this task; therefore, first customize 2 1-byte variables and then set them up in the button panel. For the right-click button, just set an ‘on’ option. Since it is controlled by a switch and needs to be maintained, an RS flip-flop must also be added in the configuration software to establish logical control. Adding buttons to the screen does not allow the state to be maintained.