analog to digital converter . . . . . . . . . . . . . . . 4 - UPGNet

351579-YTS-B-0608THE MILLENNIUM ® SIMPLICITY ® CONTROLINTRODUCTION AND OVERVIEWWelcome to the new Millennium ® Simplicity ® control, a digitalcontrol system designed specifically for the Millennium ® 25 to 40Ton single package rooftop unit. The Simplicity ® is composed of72 monitored and controlled input and output points. The controllogic of the Simplicity ® extends on the rules built in to theSynthesys control, and provides character displays in addition toLED flashes to display information to the technician.The Simplicity ® digital control performs all of the control andmonitoring functions that were originally done by separatediscrete relays, controls, and interlocking hardware. Thisreduces manufacturing, service, and maintenance costs. TheSimplicity ® digital controller includes sophisticated control ofthe individual components of the HVAC cooling/heating unit,and has built-in rules that protect those components andoptimize the control to its environment. The cooling and heatingmodes are protected against frequent cycling, slugging,multiple restarts, etc.The Millennium ® Simplicity ® control is resistor-configured forConstant Volume (CV) units or Variable Air Volume (VAV) units.The option settings for a specific option configuration will bemade as part of unit test at the factory; however, if there isdoubt about how a unit is responding in the field, check theoption setting for the unexplained action.If connected to a network, the control requests an address by apress of the Address/Down button.DIAGNOSTICS VIA LEDThere is an LED on the board that shows the status of thecontrol and alarms (see Status LED Table). There are twocharacter displays, one 2-digit and one 4-digit, to indicatedetails of run conditions and alarms (see Alarms Table in theTrouble Shooting section of this manual).When the Alarm / Change Data button (See Figure 2 Simplicity ®Controller Push Buttons) is pushed and released one time withinfive seconds, it will re-enunciate the last five alarms on theDisplay.ProgramTest / Reset / UpAlarms / Change DataAddress / DownFigure 1: Simplicity ® ControllerOne result is that the system may not immediately respond asyou expect. For example, internal digital timers may delay thestart of a compressor even though the thermostat calls forcooling. The control may be in the middle of a timing sequence;without the observer knowing what has already happened andthe status of current inputs, the system may take action notexpected by the tech.In the Simplicity ® control, there are:• a list of user-selected option settings and setpointsrecorded within the control;• inputs monitored by the Simplicity ® ;• specific fixed rules and timings built in to the control• outputs to compressors, heat, economizers, and otheroptions.The Simplicity ® has a real-time clock function, with minimum often hours “Time-of-day retention” with unit power off.Figure 2: Simplicity ® Controls Push ButtonsWhen this button is pushed and released two times within fiveseconds, it will clear all stored alarms.The error details for most conditions are stored in summary inthe Simplicity ® Control and can be accessed by the digitaldisplay, personal computer interface, or Palm Pilot (Someinterfaces still in development).Diagnosing requires patience because of internal timings.Normal observable conditions are the same - contactor 1Mpulled in, compressor 1 running - but the control does notidentify what it has just done or is about to do. The Simplicity ®control will take action according to its internal rules eventhough action requests come from smart thermostats. A call forcooling, for example, will be compared with supply airtemperature before energizing a cooling stage.ERROR HISTORYThe Simplicity ® control stores up to 5 of the most recent alarmsin a First In, First Out (FIFO) manner. As the control collectsJohnson Controls Unitary Products 3