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ORANGE COUNTY 230923-6 <br /> <br />Emergency Management Warehouse Building Dehumidification Extension of Existing Direct Digital <br /> Control System for HVAC <br /> <br />It shall be possible to trend log any number of points at least equal to twice 1 <br />the number of connected physical points. Any object in the system (physical 2 <br />or calculated) may be logged. 3 <br /> 4 <br />Once established, trend logs shall continue until deleted by user. Data 5 <br />storage sufficient for at least 30 days shall be provided for each trend log. 6 <br /> 7 <br />Custom report development. 8 <br /> 9 <br />Utility and weather reports. 10 <br /> 11 <br />Application editors for controllers and schedules. 12 <br /> 13 <br /> 14 <br />DIRECT DIGITAL CONTROL UNITS 15 <br /> 16 <br />General: Multiple digital control units (CUs) shall be provided. CUs shall be fully field programmable and the 17 <br />use of firmware-based application specific controllers is prohibited. All control functions shall be resident 18 <br />in the CUs, including those involved in building-wide strategies. 19 <br /> 20 <br />Control Units: Modular, comprising processor board with programmable, nonvolatile, random-access memory; 21 <br />local operator access and display panel; integral interface equipment; and backup power source. 22 <br /> 23 <br />Control units shall fully comply with the system architecture and communication requirements specified 24 <br />hereinbefore. 25 <br /> 26 <br />Units shall monitor or control each I/O point; process information; execute commands from other control 27 <br />units, devices, and operator stations; and download from or upload to operator workstation or diagnostic 28 <br />terminal unit. 29 <br /> 30 <br />Stand-alone mode control functions shall operate regardless of network status. Functions include the 31 <br />following: 32 <br /> 33 <br />Global communications. 34 <br /> 35 <br />Discrete/digital, analog, and pulse I/O. 36 <br /> 37 <br />Monitoring, controlling, or addressing data points. 38 <br /> 39 <br />Software applications, scheduling, and alarm processing. 40 <br /> 41 <br />Testing and developing control algorithms without disrupting field hardware and controlled 42 <br />environment. 43 <br /> 44 <br />Provide local operator interface to provide for download from or upload to operator workstation or 45 <br />diagnostic terminal unit. 46 <br /> 47 <br />Standard Application Programs: 48 <br /> 49 <br />Electric Control Programs: Demand limiting, duty cycling, automatic time scheduling, start/stop time 50 <br />optimization, night setback/setup, on-off control with differential sequencing, staggered start, anti-short 51 <br />cycling, P/PI/PID control as hereinafter, DDC with fine tuning, and trend logging. 52 <br /> 53 <br />HVAC Control Programs: Optimal run time, supply-air reset, and enthalpy switchover. 54 <br /> 55 <br />Chiller Control Programs: Control function of condenser-water reset, chilled-water reset, and equipment 56 <br />sequencing. 57 <br /> 58 <br />Programming Application Features: Include trend point; alarm processing and messaging; weekly, 59 <br />monthly, and annual scheduling; energy calculations; run-time totalization; and security access. 60 <br />61 <br />DocuSign Envelope ID: 7668B866-6C26-485C-9A45-DAAB5D4BD951