PC-PLC connection

[Guest Wouter]

Hello, I'm a Belgian student and I'm looking for more information about the Mitsubishi FX0 PLC. The information I need is more specifically about creating a connection between the PLC and a computer. I would like to make a Visual Basic program that can communicate with the PLC. I want to read parameters from the PLC with a computer. Witch parameters can I read from the PLC? Outputs, dataregisters, timer parameters...? Is it also possible to copy the PLC program -> completely <- to the computer and save it? And how would that be done then? If you know a n y t h i n g about PC-PLC connections with Mitsubishi FX PLC, can you please help me with it? It would help alot and I would thank you for the rest of my life Thank you, A desperate student who needs PLC help

[Sergei Troizky]

Hi, First of all, why FX0? It is obsolete and discontinued product. You should use FX1S as non-expandable, and FX1N as expandable PLC. For communications of VB(or VBA) with PLC there is a DDE driver called MelDDE32. Any device may be read from or written to PLC, using this driver. It is used typically in Excel VBA environment (but not necessarily). For uploading a ladder program from PLC you nead a programming software for the PLC. You should already have one, otherwise how the PLC was programmed?

[Guest Wouter]

Ok I would use Melsec to program it, but that's another question. The point is that I'm wondering if it's possible to create a VB program yourself to copy the complete plc program to a pc and after that, load it back up? The reason I use the FX0 PLC is because other models are too expensive for me. I'm just a student, remember? Anyway, I read something about the DDE driver but I think you have to pay for it, right? Well that's what I'm -not- going to do. I have a small piece of Visual Basic code with witch you can read if an input is active - inactive. But I was wondering, can you read / change timer parameters too with a Visual Basic program?

[Sergei Troizky]

Wouter, FX1S is not more expensive than FX0. But it's solely up to you, of course. By Melsec you most probably mean Melsec Medoc. If yes, this is a very good, though obsolete, software. It is for DOS but perfectly works under any Windows. By my opinion there is no practical sense to write the ladder up/downloading software yourself. I simply cannot imagine practical need for this. Do not invent a bicycle. Conserning DDE driver, give me your e-mail address.

[Guest Wouter]

Dear Sergei, The reason that I want to make software to upload/download ladder from PLC is because I want to make software to monitor all I/O's of the PLC, read timer parameters,... And I want to make it possible to switch programs easely. For example: Let's say I want to produce purple paint today. Then I select my PLC program from a list to make purple paint. If I want to let my machine mix another color, then I just select another program and load it up. This is ofcourse a really stupid example but I think that would make things easier if you produce things for witch certain recepies are required. This way you save alot of PLC memory and you will also reduce your PLC scan-time My E-Mail adress is: wouterverscheure@hotmail.com Thank you, Sergei!

[DesertDog]

If you write your code using variables you can download the values (amounts of basic colors) for recipes instead of downloading an entire program for each item. Most touchscreen and HMI packages already have recipe management built in just for this.

[Guest Wouter]

I know about the touchscreen packages and stuff but I don't have the ca$h for it. I'm just looking for information about PLC-PC connections to see what's possible and what isn't. I know it's possible to read I/O's, read the value of a dataregister,... but is it also possible to change timer parameters and dataregisters? If anyone can help me with it, please let me know Wouter

[Paul416]

Take a look at this link http://www.mrplc.com/dl/index.php?action=v...ntry&entryid=49 I uploaded it here a while ago. Its written in QuickBasic but should be easy enough to convert to VB. It will read & Write to the fx series. Should provide you with a few pointers. If your into C++ I also have some stuff Ive been playing with to read & write to FX PLC's

[DesertDog]

I've never written a program to link to the PLC but the touchscreens I've used could modify data registers and timers/counters can use data registers as presets.

[Sergei Troizky]

Wouter, I received the following after sending you an e-mail. Check the address, please. Delivery to the following recipients failed. wouterverscheure@hotmail.com

[Guest Wouter]

Hello Sergei, The E-mail adress is correct but I think that the file is too large to receive in my mailbox. Can you try the following adress please? franz.verscheure@pandora.be Thanks for your help! Wouter

[panic mode]

Just to give you a full picture: If you don't want to develop your own driver, there are commercial products that do the job. One of them is by Mitsubishi of course. It is called MX Components. Advantage of MX Components is easy setup of new connections once you learn how to get one working. RS232, Ethernet or whatever you choose is transparent to your application. Last version i was using is 3.0 which is more powerfull than 2.0 (make sure to always get the latest version), although even 3.0 didn't allow full connectivity of GX Developer 7.xx. Just to name one example: If you have CC Link network of 2,3 or more PLCs which are not same family (In our case master was Q, but other PLCs were QnAS) you get to connect only to master (or PLCs that are same family as master). panic mode

[Guest wolf]

Hello I made a few PC-PLC connections using Meldde and Labview or Visual Basic, you can read and write any PLC address. Like Sergei i don't see any advantage in download and upload the plc program, for that use the Melsec Medoc.

[ivel]

Hi there.. can i see your LabVIEW code example in communicating Mitsubishi FX? either thru MX component or basic serial is ok.