US 12,265,384 B2
Methods and system for minor loop feedback fallback
Kenneth Junk, Marshalltown, IA (US)
Assigned to Fisher Controls International LLC, Marshalltown, IA (US)
Filed by Fisher Controls International LLC, Marshalltown, IA (US)
Filed on Oct. 12, 2015, as Appl. No. 14/880,806.
Application 14/880,806 is a continuation of application No. 13/922,046, filed on Jun. 19, 2013, granted, now 9,411,321.
Claims priority of provisional application 61/661,930, filed on Jun. 20, 2012.
Prior Publication US 2016/0033942 A1, Feb. 4, 2016
Int. Cl. G05B 9/03 (2006.01)
CPC G05B 9/03 (2013.01) 26 Claims
OG exemplary drawing
 
1. A non-transitory machine-readable medium comprising instructions which, when executed, cause a processor to at least:
determine a first minor loop feedback value based on a first control mode associated with a first minor loop feedback control path and a first sensor;
control a process control device at least partially based on the first minor loop feedback value;
identify (a) the first minor loop feedback value as outside a predetermined range of the first control mode or (b) a failure of the first control mode; and
in response to identifying that the first minor loop feedback value is outside of the predetermined range or the failure of the first control mode:
determine a second minor loop feedback value based on a second control mode associated with a second minor loop feedback control path and a second sensor; and
control the process control device at least partially based on the second minor loop feedback value, each of the first minor loop feedback value and the second minor loop feedback value to be determined upstream of an actuator of the process control device.