how can i change processor status from ....

[hidroela 0]

how can i change processor status from my application ( OPC Client on visual basic 6.0) for example the processor is in remote run and i what to change to program mode the procesor type is a plc-5 we are conecte to ethenet card using rslinx 4.2 gateway any advice would be apresiated email hidroela@msn.com

[Chris Elston 78]

Can I ask why you would want to do this? Typically if your programming the PLC you can leave it in remote run. I am curious to know why you want to program the PLC using VB. That seems dangerous to me.

[hidroela 0]

we want to control some outputs from a remote area for troubleshooting purposes in colaboration with other so there is no safety issue involve iam not a guru on this so if i am doing something incorrect let me know

[hidroela 0]

Basically we want to have and application outside rslogix 5 that let us activates some outputs with a better and ease GUI GUI

[hidroela 0]

The problem is that when I try to write to the table on the processor to turn on\off and output and it is on remote rum it don’t let me do it so what I am o do is change the processor status while I am doing the test and after that change back I hope that now you have sufficient elements to answer my question

[Snerkel 0]

The reason you can't change the output state when in run mode is that the ladder logic will be over-riding your OPC control. An easy way to do this would be to setup buffered outputs in a seperate program file. The program file would be called from ladder 2 using a conditional JSR instruction, disable the JSR with your OPC program then you can control the outputs, re-enable the JSR to return control to the PLC

[Snerkel 0]

This simple example may help demo1.RSS

[Guest Guest]

Thanks Snerkel I will try your subjections But my question is if I can change the processor status from my application ( OPC Client on visual basic 6.0)

[Guest jimmy]

When you do what Snerkl says to do you won't need to change the PLC status...thats the point here...

[Guest]

Greetings, hidroela, I’m not sure that I really understand exactly what you’re trying to do ... so feel free to ignore this if it doesn’t apply ... yes, you (probably) COULD change your processor’s mode status by using VB ... BUT ... you probably don’t really want to ... first of all, you must understand that when you go to the “program” mode, all of the PLC’s (discrete) outputs will go OFF ... that means that even if your VB application tries to turn on an output, the output will NOT turn on in the field ... specifically, VB might be able to write a “1” into an output address ... but the actual field device will still be OFF whenever the processor is in the “program” mode ... but if you’re still interested in having VB change the processor’s mode, here is a plan of how to proceed ... (note: I’ve never actually seen this done before ... but I’d bet more than pocket change that it could be done) ... first you need to find out what specific command is used to tell the PLC to go to the “program” mode ... you might be able to research the command syntax in this book: DF1 Protocol and Command Set Reference Manual you might also try “wire tapping” an RS-232 communications line between RSLogix5 and a PLC-5 processor ... you could try using an RS-232 “monitoring” software package to capture the data stream while RSLogix5 tells the PLC to go to the “program” mode ... a few experiments along these lines should reveal the proper command ... once you have the proper command syntax, you should be able to program your VB application to issue the command ... but once again, you need to realize that once the PLC goes into “program” mode, all of its (discrete) outputs will turn OFF their field devices ... if this is not what you want to happen, then you might be wasting your time trying to have VB make the mode change ... finally, a disclaimer ... I've never actually done anything like this before but it seems like it would work ... if anyone could offer any constructive criticism or other type of advice, I'm sure that hidroela would appreciate it ... hope this helps ... Ron

[hidroela 0]

thanks all you felas for your help like i say before iam new n this material of plc i dint have time to play with all your sujestion but i will one more time thanks