CI 773F stops polling?I
I have an AC902F with two CI 773F. On the first profibus I have lots of frequency converters, and it works fine. On the other profibus I have some Eurotherm thyristor units, which works fine for 5-10 minutes, thereafter the units indicator for bustraffic on the thyristor units goes black. but the CI 773F still thinks its ok (All green indicators). If I unplug the bus from the CI773F, it still thinks its fine (?). If I restart cpu the communcation resumes again for another 5-10 minutes. It seems the CI 773F works fine for 5-10 minutes but then stops talking on the bus, and then also does not discover if I unplug the profibus from it. If I unplug the bus after a restart before the problem occurs the CI 773F discovers unplugged bus immediately.
Anyone have any suggestions?
Best regards Magnus Bergsten
Voted best answer
check that grounding & Shielding is according to the installation manual. Also verify that the Profibus is actively terminated on both ends.
You can also try to switch the Profibus Lines from CI 773F one to CI 773F two and vice versa. See if the error stays with the CI (which would indicate a broken CI 773F) or moves to the other CI now (which would indicate a bus problem)