Carrier 19XR User Manual

Also see for AquaEdge 19XRV series: Start-up, operation and maintenance instructions Start-up and service instructions Installation instructions Start-up, operation and maintenance instructions Start-up and service instructions

Contents

11General — The 19XR hermetic centrifugal liquid chillercontains a microprocessor-based control center that monitorsand controls all operations of the chiller (see Fig. 9). Themicroprocessor control system matches the cooling capacity ofthe chiller to the cooling load while providing state-of-the-artchiller protection. The system controls cooling load within theset point plus the deadband by sensing the leaving chilled wateror brine temperature and regulating the inlet guide vane via amechanically linked actuator motor. The guide vane is a vari-able flow pre-whirl assembly that controls the refrigeration ef-fect in the cooler by regulating the amount of refrigerant vaporflow into the compressor. An increase in guide vane openingincreases capacity. A decrease in guide vane opening decreasescapacity. The microprocessor-based control center protects thechiller by monitoring the digital and analog inputs and execut-ing capacity overrides or safety shutdowns, if required.PIC II System Components — The chiller controlsystem is called the PIC II (Product Integrated Control II). SeeTable 1. The PIC II controls the operation of the chiller bymonitoring all operating conditions. The PIC II can diagnose aproblem and let the operator know what the problem is andwhat to check. It promptly positions the guide vanes to main-tain leaving chilled water temperature. It can interface withauxiliary equipment such as pumps and cooling tower fans toturn them on when required. It continually checks all safeties toprevent any unsafe operating condition. It also regulates the oilheater while the compressor is off and regulates the hot gas by-pass valve, if installed. The PIC II controls provide critical pro-tection for the compressor motor and controls the motor starter.SPEEDVOLTSAMPSHzKwTORQUEPasswordRUNNINGREMOTEJOGAUTOFORWARDREVERSEPROGRAMPRO-GRAMForwardReverseENTERRUNJOBAUTOMANSPEEDVOLTSAMPSHzKwTORQUEPasswordRUNNINGREMOTEJOGAUTOFORWARDREVERSEPROGRAMPROGRAMForwardReverseENTERRUNJOBAUTOMANMANUAL RESETOPTIONALMETERPACKAGESPEEDVOLTSAMPSHzKwTORQUEPasswordRUNNINGREMOTEJOGAUTOFORWARDREVERSEPROGRAMPROGRAMForwardReverseENTERRUNJOBAUTOMANDANGERHIGH VOLTAGE+ -INITIAL DC BUSMEASUREMENTPOINTDC BUS BARMEASUREMENTPOINT+-VFDMODULECOOLING LINESCOMPRESSORMOTORDISCONNECT TXVCONTROLAND OILHEATERDISCONNECTOIL PUMPDISCONNECTINTEGRATEDSTARTERMODULE(ISM)LINELOADFig. 7 — Variable Frequency Drive (VFD)Fig. 8 — Variable Frequency Drive (VFD) Starter Internal View