Allen-Bradley · Logix 5000 Controllers
This fault indicates an invalid previous Control Variable (CV) value. For PIDE, this occurs if CVPrevious is less than 0 or greater than 100, or outside CVLLimit/CVHLimit when in Auto or Cascade/Ratio mode. The instruction limits CVn-1. In the PPID instruction, Sts_CVPrevBad is set only if Inp_UseCVPrev is enabled (1) and Inp_CVPrev value is invalid; its allowed range is always between Cfg_CVEUMin and Cfg_CVEUMax.
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Access the PIDE or PPID instruction within the programming software and review the CVPrevious (PIDE) or Inp_CVPrev (PPID) parameter value
For PIDE, ensure CVPrevious is between 0 and 100, and also within CVLLimit and CVHLimit when operating in Auto or Cascade/Ratio modes
For PPID, verify Inp_CVPrev is within Cfg_CVEUMin and Cfg_CVEUMax if Inp_UseCVPrev is enabled
Verify the integrity and source of the CVPrevious or Inp_CVPrev value if it is derived from external logic or inputs