I have 890 with profibus and encoder option cards installed. Problem developed about a month ago where during start up of the machine drive control card seems to be overloaded somehow, STATUS led goes from green to red then dims and this cycle repets itself few times. Sometimes drive manages to start up, sometimes staus led goes off, and display freezes, doesn't react to any buttons on it.
Drive was replaced, including the control card. But same problem persists. Profibus and encoder cables were unplugged for test, still same problem.
I can see that when control card is resetting itself, so to speak, it looses it's 24VDC output. But this voltage doesn't supply anything externally.
Anybody hass any ideas where to look further?
Again, drive was replaced with brand new and same problem persists.