Lets say I want to show on the HMI when an 24V air valve opens and closes

Greg7683

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So if I want to see when the air valves open and close on a screen on the HMI is all that needs to be done is to address the bit with the address that open and close. It's a weintek HMI by the way.
 
The valve must have two limit switches one for the open position the other for the close position,those limit switches wired to PLC input card and with some programming you can check the status of the valve in your HMI
 
Are you needing advice about how to detect the position of a valve or air driven device, or are you needing advice about how to display the state of the existing limit switch or valve command?
 
The air valves have 2 solinoeds and some have one I would like to have it show up when the signal hits the solinoeds that makes the cylinder move out and when it is back in so yeah
 
The air valves have 2 solinoeds and some have one I would like to have it show up when the signal hits the solinoeds that makes the cylinder move out and when it is back in so yeah

Okay, I believe what you are trying to do is display an animated cylinder based on the solenoid command.

Now we need to know what HMI/software you are using.
 
When you display the state of the solenoid valve you are showing the world what you told the machine to do. When you display the state of a properly actuated limit switch you are showing the world what actually happened.


So in the PLC program there are limit switches what do they look like. Mostly I see are NO and NC switches and one with a arrow pointing up or down.
 
Okay, I believe what you are trying to do is display an animated cylinder based on the solenoid command.

Now we need to know what HMI/software you are using.


Yup ether small cylinders that are ether in or out or a set of air valves that has the solenoids lit up ether on the top or the bottom. Am I asking for too much lol.


The demo that comes on here show some good animation.
 
Limit switches and solenoid valves are physical devices on your machine. Solenoid valves are wired to PLC outputs. They are turned on and off by the PLC program. Limit switches are wired to PLC inputs. They tell the PLC about conditions on the machine.
Inside the PLC ladder logic program the state of a limit switch will be shown by either a NO (XIC) instruction or a NC (XIO) instruction. To make things even more confusing the limit switch itself can have NO and NC contacts. A NO instruction in ladder logic assigned to an input wired to a limit switch will show as TRUE when there is current flow at the input terminal and FALSE when there is no current flow.
 
Limit switches and solenoid valves are physical devices on your machine. Solenoid valves are wired to PLC outputs. They are turned on and off by the PLC program. Limit switches are wired to PLC inputs. They tell the PLC about conditions on the machine.
Inside the PLC ladder logic program the state of a limit switch will be shown by either a NO (XIC) instruction or a NC (XIO) instruction. To make things even more confusing the limit switch itself can have NO and NC contacts. A NO instruction in ladder logic assigned to an input wired to a limit switch will show as TRUE when there is current flow at the input terminal and FALSE when there is no current flow.


The only limit switches we have other then the ones built into the Servo Amps are ones with the arms that will cut off the power if a machine goes too far.
 
You will use a bit lamp instruction set up to the address of the solenoid output. This will show, as posted, what the state should be.

An observation here is that you are not drawing the connections between devices in the program and the devices in the field. I suggest you spend some time with the prints and the program so that you can get a better grasp of what is happening. If possible, do this with the physical machine by tracing the circuit from the power to the limit switch and back. You may have to add proximity switches, limit switches, or photo eyes to get your desired result.

Also, if you look at my posts there is a whole string of weintek questions I've asked that give an idea of building an hmi with easybuilder.
 
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You will use a bit lamp instruction set up to the address of the solenoid output. This will show, as posted, what the state should be.

An observation here is that you are not drawing the connections between devices in the program and the devices in the field. I suggest you spend some time with the prints and the program so that you can get a better grasp of what is happening. If possible, do this with the physical machine by tracing the circuit from the power to the limit switch and back. You may have to add proximity switches, limit switches, or photo eyes to get your desired result.

Also, if you look at my posts there is a whole string of weintek questions I've asked that give an idea of building an hmi with easybuilder.


Everyone here talks about prints lol we never had prints of any kind here we have to track every wire cable and sensors by hand even the PLC program is blank no labels just X's and Y's I thought that I would of just had to add the address to the switch that opens and closes to a bit or a lamp with a picture to get what I am looking to do Hmm
 
Tarik1978 threw you a curve in post #2 when he suggested you need limit switches to detect the status. When all you have available to be displayed is the fact that a solenoid valve is energized or not, that's what you work with. Your comment in post #3 is accurate. All you have to do in the HMI is set up an object that changes color based on the state of the PLC output address controlling the valve.
For this example a limit switch is a more reliable indication of the state of the machine than simply showing the state of the solenoid valve controlling the air flow to the cylinder. There are several things that can go wrong so that when the solenoid valve is energized the cylinder won't move. There could be something blocking the motion. The air pressure could be insufficient to move the load. The power could be disconnected to the output module. The solenoid could be burned out. The wire between the PLC output and the solenoid could be disconnected. Etc, etc, etc.....
 

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