I had a Siemens S7-414 system working in hot redundant mode.
there was some power supply outage and since then the PLC is in stop mode and despite my best efforts i could not get the CPU in run mode even after resetting memory.
first i switced off one of the CPU's power supply to take it out of system and concentrate on one CPU only.
for the other CPU:
I took out the batteries,the flash card, all the profibus connections and did a memory reset. now when i switch it on (in stop mode) then for 4-5 minute the STOP mode LED blinks and then it goes steadsy amber. after that when i put it in run the run LED flashes but it never goes green and goes to STOP mode again.
My question is: If i have cleared the memory,took out all profibus connections,no flash card why does the CPU does not go to RUN mode. A blank CPU must go to run mode i believe?
there was some power supply outage and since then the PLC is in stop mode and despite my best efforts i could not get the CPU in run mode even after resetting memory.
first i switced off one of the CPU's power supply to take it out of system and concentrate on one CPU only.
for the other CPU:
I took out the batteries,the flash card, all the profibus connections and did a memory reset. now when i switch it on (in stop mode) then for 4-5 minute the STOP mode LED blinks and then it goes steadsy amber. after that when i put it in run the run LED flashes but it never goes green and goes to STOP mode again.
My question is: If i have cleared the memory,took out all profibus connections,no flash card why does the CPU does not go to RUN mode. A blank CPU must go to run mode i believe?