A Fresh Engineer (Customer) asked a question.
Can a laptop be used as a user interface where inputs can be sent to the plc program?
I am very new to PLCs. I am trying to make an automated pressure testing unit. I understand all of the coding for the system except the part where a human has to type in the pressure and time. This PLC will be controlling an air pump and many other devices. The first step to the process is someone needs to walk up to a computer or interface of some sort and input their set pressure and time they want to test. Once they press enter, I want the PLC to take the pressure and time inputted and start the pressure test. Every test will be a different custom pressure each time.
I want to know how is it possible for me to do this? What would I need to use to send numbers from the pc to the PLC?
There are about 3000+ ways to do this and it depends on what your final product will be. It also depends on how temporary or long term the solution is. Typically in industrial applications, this is accomplished with local HMI (Human Machine Interfaces) touch screens. There are a number of ways to do this with free software for debugging purposes but these aren't intended to be used long term as they're not operator friendly. Other approaches utilize web based interfaces that can be accessed from any network computer. These range from Raspberry Pi running NodeRED to full SCADA systems like Ignition (which is arguably the best SCADA system in use today). LabVIEW could be used to create a GUI. advancedhmi.com allows you to create an HMI on a PC as long as you have Visual Studio installed on your target machine.
Hi @A Fresh Engineer (Customer)
+1 @RBPLC (Customer)
Usually, a PC would be used as the HMI if data logging is also required. If the only thing that the PC is doing is entering pressure and time and starting the process, then I would recommend an HMI as well.
EA9 HMI Series
https://accautomation.ca/series/c-more-hmi-series-panel/
If a PC is required, then take a look at Node-RED. Here is a link to the series.
https://accautomation.ca/series/node-red-iot-enabling-software/
I hope this will help you out.
Regards,
Garry
Well considering cost, buying the cheapest hmi is 668$. I have a few junk laptops lying around that could work also so using the modbus would probably be the right option. Thank you for the advice, this is my first-time using PLCs and I have no idea how the programming works. I am learning one day at a time.
Here is the link for the Click PLC series.
https://accautomation.ca/series/click-plc/
You may find some helpful hints.
Regards,
Garry
Since what you're inputting is not a lot, you could use an EA3-S3ML-R at $202.00. I've used them on THIS product (connected to a Click) for 3-years now and they've held up well.
Yea the programming side of it is not a lot at all. It's just telling the pump to get to a certain pressure and hold it there for a certain amount of time. I am also going to have electronic solenoid valves that will act as a safety feature if the pressure goes above what is put. I will look into this, thank you.
If this is a one-off testing device that will require frequent operator adjustments to set points, $668 is insignificant. An experienced person could have that HMI program finished in 30 minutes or less. A new person could still have it done in only a couple of hours and be onto the next task. Trying to modbus through an unreliable windows laptop is not worth it, you will waste many more hours making it work and you will fight Windows for an eternity. The HMI/PLC combo will be far more reliable and easier to work with/debug.
You can use the little EA3s to save cost, they're perfect for simple applications like this. HOWEVER, if your operators are adjusting this more than once per day, they are going to hate you if they have to spend their day holding inc/dec buttons. Get them the EA9 7" so they can type in their target value and get on their way. Production will also be happy as they wont be wasting so much time entering values.
there is also the headless HMI option for around $500 that will put the hmi interface on the laptop and you can control with your phone as well if the plc is networked with a wifi router
This is an option, but spend the extra $168 on the 7". Remote viewing of any EA9 is laggy and low resolution not to mention you cannot use a keyboard and have to type in values with a mouse. Any glitch in comms requires a login, but the prompt is inconsistent so it results in operators calling because it broke and you have to go out and reset it for them. You also have the PC element involved which adds an unnecessary layer of hassles for simple entry of two SPs.
Not worth it to repurpose a laptop just because it's laying around. If this is a home project for fun, have at it. Production environment, toss the laptops and keep it simple. Time is money.
In a similar vein to RBPLC's response - The P1AM-100 + P1AM-ETH can be used to host a simple webpage that acts as the user interface. This would require you to learn some C++ to get going, but luckily Arduino is an environment built with beginners in mind.