Siemens Power Management System Lockup
Siemens Power Management System Lockup
(OP)
Our facility has a power management system based on a Siemens S7 PLC polling about 100 Siemens 9610 multifunction relays which are daisy-chained together with 4-wire RS485 serial cable. We recently experienced a total loss of facility power, and the power monitoring system completely froze up for at least two minutes right when we needed it most. We have gotten very little support from the vendor in resolving this issue, so I am hoping that some of you talented individuals on this forum can help point me in the right direction. My present assumption is that the most likely answer is that simultaneous alarming of over 100 remote terminal units attempting to alert the central PLC over daisy-chained serial cable caused a communications bottleneck which lead to a system hangup. Does this seem reasonable, or am I chasing a red herring? Any thoughts would be greatly appreciated.
Steve
Steve





RE: Siemens Power Management System Lockup
Another possibility to consider is if the power glitch caused the PLC to lockup.
Someone with more experience than I in siemens PLCs might be of more help.
RE: Siemens Power Management System Lockup
I would start with the integrator or whomever built the system. If that was Siemens and it was within the last 10 years, call the Automation Technical Support line at 1-800-333-7421, they have lots of really good people there. If it is older than 10 years, you may need to pay for support depending on what you have.
RE: Siemens Power Management System Lockup
jraef: Yes, both the PLC and the RTUs are provided with UPS power. It is a very recent installation, but we are having difficulty getting the vendor to acknowledge that there is a problem. I will try the support line you suggested and see if Siemens has any ideas.
RE: Siemens Power Management System Lockup