Rio Communications Problem

I AM WORKING ON PLC5/80 CONTROLLER WITH DH+ COMMUNICATION TO OTHER PLCS AND MMIS.I ALSO HAVE 17 ROBOTS IN NETWORK WHICH ARE CONNECTED TO PLC BY RIO.
THERE ARE 6 STATIONS IN UNIT WHERE DATA IS PASSED ON FROM ONE STATION TO ANOTHER STATION.
RECENTLY I HAD ADDED TWO MORE FANUC ROBOTS AND TAKEN IN NETWORK BY RIO COMMUNICATION.
THE START COMMAND TO ROBOTS IS ISSUED FROM PLC AND IT HAS TO BE AN NEGATIVE TRANISTION PULSE. NOW ACTUALLY THE PROBLEM STARTS OVER HERE,
WHEN I HAVE PRESET OF TIMER FOR NEGATIVE TRANSITION 0.5 SECS THE PULSE IS NOT RECEIVED BY ROBOTS SO THEY DONOT START ON.
WHEN I MAKE THE PRESET 3 SECS THERE IS DELAY OF 10 SECS FOR STARTING OF ROBOTS.
WHEN THE PRESET IS CHANGED TO 2 SECS THE DELAY IS REDUCED TO 9 SECS FOR STARTING OF ROBOTS
WHEN THE PRESET IS CHANGED TO 1 SEC THE DELAY IS AGAIN 9 SECS ONLY.
SO THE QUESTION IS FROM WHERE IS THE DELAY OCCURING SINCE THERE IS NO SUCH TIMER IN PROGRAM FOR THIS PURPOSE.
THE TOTAL NO OF I/O ARE 3500 IT HAS CONFIGURATION OF 13 FULL RACKS OF RIOS.
ANY BODY WHO CAN GUIDE OR HAVE SOLUTION PLEASE COME OUT.
THEY ARE MOST WELCOME.
YOU CAN MAIL ME ON MY PERSONNEL ID ALSO MY PERSONEL ID IS

[email protected]
[email protected].

regards.

Hi SONY !

I am not much aware of PLC 5/80 & DH+ ( ? ) . From what you have written in your post it seems to be a pretty large system .
Is it some sort of welding or assembly line for automobile line ?

If you are adding new FANUC robots
- Have you got PLC code with (ALL ) comments with you?
- Have you tried with Fanuc people for help

By the way I would like to know exact application you are working on

regards
asp

It has been a while since I have worked with Fanuc Robots & RIO.

I seem to recall that you can get quite a bit of status information from the robot over RIO (ex. running program, in auto, in manual, faulted, e-stopped, motors on, etc.).

Use this status information instead of a timer to "handshake" with the robot. Apply the start command until you see the running command returned from the robot.

Also, do not apply the start command if the robot is not in auto, not faulted and not at home. To get the at home status bit you will have to get with the robot programmer to setup this status bit. Of course some of the capabilities will depend on the series of R-J controller you are using (R-J2, R-J3, etc.) Also this RIO interface is configurable on the Robot side. So you can pass program numbers, interference/clear bits, etc.

Have you checked the communications status from within RSLogix5 for the racks that the robots are setup as? If you have excessive network errors for those nodes then you could have a long delay. Also check what the update rate on the robot side is for the RIO network connection. This could have been set very high for some reason. This could also vary by controller version/series. I have also seen this be effected if the robot is using Karel and the programmer has spawned some background task that are hogging the controller processor.


Darren