CraigROCK

Hi pturmel, Glad to see my train of thought was along the same lines as an expert in the field!  I have installed a new CPU and sailed through the process to reinstall. System now back up and running!  Thanks again for the quick reply and i will be using this as an example to strengthen my existing argument to get all PLC's UPS protected!   Regards,   Craig

Hi pturmel, Thanks for the reply. I did suspect that was the root cause of the issue, swapped it and then the site had another power surge over the weekend knocking the system out again. Come in on monday and the program has been dropped again (no EPROM fitted to CPU from what I can see)!  This time, the BOOT DHCP tool doesn't seem to be writing the IP address to the CPU as I cant ping it! Going through RSLinx it also cant see it, when i configure the driver for IP, using the IP address assigned.  This is actually the first time I've come to use AB PLC's so I'm rapidly running out of things to try - searches on these forums have been a big help in getting me to the above point, along with what ive picked up from Siemens! My next steps I think will be to replace the CPU (if held onsite) unless anyone has any further advice/tips?

Hi all, I'm new to Allen Bradley but have some experience with TIA/STEP 7 - not that it relates to this issue! We have 2 side by side systems but running a SLC 5/05 CPU, with the same program but different IP addresses, connected via a network switch. All has been fine until both were power cycled - system 1 CPU program has dropped but not system 2? The IP address for system 1 has been reset and can't be pinged from either the switch (but 2 can) or directly connected to the PLC port. Steps I have carried out as below, so would appreciate anyone skimming over and pointing out where I've gone wrong/something else to try; - Used BOOT P DHCP tool directly connected to system 1 plc, add relation assign original IP address, click Disable BOOT P. - Attempt to ping (after changing laptop IP to same loop but different node) = no connection - same cable used to connect to switch and ping system 2 which worked so cable and adaptor settings good. -not going to help with the immediate problem but battery swapped out for new on CPU. Any assistance and advice appreciated!