Freelance 2000 ver 3.2, Digivis communication with PS_2 aborted!
Thanks for your replay about lateral communication error. It now works fine.
I have this even worse problem now after a power breakdown this weekend.
The Digivis-program on both my workstations, OS_1 and OS_2, have problem communicating with one of my PLC:s PS_2. Gives the error I wrote in the header.
No problem at all with PS_1.
If i Try to ping the PLC I get timeout in every fourth every sixth ping.
I have exchanged the coax cable and the terminate resistor.
I have also restarted the system and loaded the program with Load whole station.
The strange thing is that I can download program without any trouble.
What do you think? Any idea?
Is there some other way to make a reset on the CPU board?
Best Regard Anders
I had a similar problem, not with Digivis and a PLC, but between my PLC and a deported screen (panel 800). I could loaded the program in the panel and the PLC, but when they communicated together, there was timeout problem.
Therefor even if you can download your program, there may be still another probleme, like me.
For my part, I think the ethernet cable was disturbed with other cables (power cables, instrumentation cables).
Coax cable? This is 10base2 network? How many devices are on this network line? How many traffic does this devices make?
The issues you describe could have 2 sources:
- Electric network issue. All cables, resistors, T-pices and network ports well on this network segment?
- Overload. A 10base2 network tends to be bad if too many data is transfered. Does some device flood the network with data? Are there new devices? Does some of your co-workers stream its music collection over the freelance net? (was a real case on my plant!)
This issue appears since you changed the LatCSnd cycle time, so i would suggest you to change it back. Freelance latcom are not many data, but maybe this was the last little pice to overload an already heavy loaded net. The lateral communication problem can be solved by setting the LatCRcv to >2s, if longer signal times are ok for you.
By reconfigure the ethernetcommunication to use the AUI-port instead of coax and use a microtranciever to convert from coax to dsub we now have got the communication to work. This was done using a terminal directly to the rs232 port on the CPU.
This is only a workaround, we still have an error in the coax port but it doesn't affect the function of the system at the moment.