Redundancy in programmable logic control for on-site power generation applications
- Zenith Controls, Inc., Chicago, IL (United States)
Solid state relay control systems have been used for many decades as the {open_quotes}brains{close_quotes} of on-site power generation systems. However, with the ever increasing capabilities of programmable logic controllers (PLC) which are utilizing the features of advanced microprocessor chips, coupled with the complex control logic required for modern power systems, relay logic is now used less and less for system control. PLC hardware components have been demonstrated to have extremely high levels of reliability - typically for a central processor unit (CPU) mean time between failure (MTBF) is in excess of one million hours of operation. However, some system specifiers are very conservative in their approach to system design based upon PLC control versus relay control. Accordingly, different types of redundant PLC control systems have been developed, with the redundant architecture schemes dependent on the needs of the specifier and/or end user.
- OSTI ID:
- 405630
- Report Number(s):
- CONF-951208--
- Country of Publication:
- United States
- Language:
- English
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