The pump is disabled when the associated plant equipment is disabled and:
have_req=true): either the equipment has been proven
off for dtOff or is not requesting flow.have_req=false): the equipment has been
proven off for dtOff.When the flow request point is available, the default value for
the pump disable delay dtOff is increased from
3 min to 10 min to ensure that flow is not
cut off too soon.
Used in Guideline 36 for disabling dedicated primary pumps in chiller and boiler plants.
The enable signal u1 is yielded by the staging
event sequencing logic.