mCq pCO - Standard + Heat Pump - McQuay

Conditioning: pCO Standard chiller + heat pump User Guide ver. 2.9 02/11/99Water temperature regulationWater temperature can be regulated by means of a Proportional (P) or Proportional + Integral(P+I) control action, according to your specific application requirements.PROPORTIONAL CONTROL:since the set-point represents the ideal working condition, the pCO controller will operate itsconnected devices so as to reach the set-point in a proportional way, that is proportionally tothe distance between the actual condition and the set-point.The control action depends on the differential zone selected by the User:within this zone pCO will minimize the action of the connnected devices as the actualconditions get closer to the set-point and vice versa.PROPORTIONAL + INTEGRAL CONTROL:besides what performed by the proportional mode, the P+I control action will also rely on the'time' factor. A time constant (in seconds) will determine the velocity with which the controllerperforms its actions (less seconds, higher velocity). Usual time constant = 600 seconds.SET-POINT AND DIFFERENTIALSET-POINT ==> selectable in ºC; ideal working condition.DIFFERENTIAL ==> selectable in ºC; indicates the working range of the controller.temperature control zonesetpointdifferentialwatertemperatureIn the application shown in the figure above the set-point has been set so as to represent theCENTRAL point of the regulation zone.Pag.23/61