Program Download

[Guest Meehans]

Hello all. I'm afraid that I have very limited knowledge of PLC's, expecially Mitsubishi ones but I do have a question pertaining to one that you might be able to help me with. I have a Mitsubishi Melsak A2AS cpu, display mta-g1, type 0095B that has a program on it I would like to re-use. I want to download the program from the PLC and upload it to a new PLC. Is this possible and what would I require to do it? Am I better off taking it somewhere? Any insight would be appreciated. David

[panic mode 246]

First you need to sort out terminology. Downloading means transfering to PLC, uploading is transfering from PLC. To do transfer of PLC program with any PLC you will need: 1. computer with proper software (Mitsubishi currently sells GX Developer) 2. programming cable (for this PLC you can use SC09 cable) 3. if uploading (transfering from PLC to PC) and you don't have original program, you still have to create new project with same CPU. You can only upload into existing project and if the CPUs match. 4. setup communication to mach PLC and connection method (unter Online\Transfer Setup simply click on direct connection and eventually change COM port number). The A series CPU can't talk faster than 9600bps. 5. initiate transfer. For GX Developer, open Online menu and select transfer from/to PLC depending on what you do and highlight parts of program you want transfered (ladder, parameters, data, etc.) Edited 19 May 2004 by panic mode

[Sergei Troizky 26]

And you need to do something else. You have to transfer to the new PLC not only the program, but also the contents of latched memory- the data registers, bits, and probably counters (very unlike). Data registers contents upload/save/recall/download is supported by the programming software but is not part of the program upload/download procedure. For the latched bits and counters there is not, as far as I know, any way to let the software do it. You will have to check their status online, put it on your records and manually copy their state when online with the new PLC. Edited 20 May 2004 by Sergei Troizky