MMS Comuunication problem
recently i have faced a problem with my PM861 controllers,
i was downloading application to Controller_1 but it got interrupted with "Error In communication Link" and got the system Alarm "Network connection to Controller_1 is lost"
and it stopped communicating, Graphics faded(no realtime data), and cant even PING.
i have checked all the CN cables and they were fine. but CI854 and Controllers Fault LED was indicating RED, anyhow i restarted the Power to controller and downloaded the application back...
now the real problem started , there were few MMS communication variable between Controller_1 and Controller_2..
after restating the controller MMS communication has been broken between C_1 and C_2 (Controller 1 and 2)..
i have tried in all the ways like firmware upgrading of C_1 and Coldrestart of C_2 and everything i have done but in-vain...
later i found that C_1 to C_2 is not working but C_2 to C_1 is working fine...
and finally i have replaced the C_1 controller also, still no communication with C_1 to C_2 ( but C2 to C_1 is fine ).
i have seen one System Alarm " IAC down" and after 20 mins another alarm "IAC up" in C_2 controller
what could be the problem?? can someone give me an idea to solve this problem,
are there any settings we need to check for MMS communication..like any IAC settings
looking forward to your reply,
Thanks in adv.
There are some limitation on IAC message such as message length mustn't exceed 1.5Kb.
Also make sure that:
1. Both controllers doesn't have conflicting tasks.
2. Time on both controllers is the same.
In 3BSE035982-510 (AC 800M 5.1 Communications prototocols) one troubleshooting procedure is given:
"...right click the controller, select Remote System, and click Show Diagnostics for Communication Variables..."
Try, it might help.
BTW, why do you need communication variables for the MMS? I think it is better way to define variable that you would like to transfer in the "Global Variables" of the source controller (C1 in your case). Later you add it into MMSDefxxxBool(-Dint, -Dword or -Real) control module to transfer value to the target controller (C2). Let me know if you need an example.