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ORANGE COUNTY 230923-9 <br /> <br />Emergency Management Warehouse Building Dehumidification Extension of Existing Direct Digital <br /> Control System for HVAC <br /> <br />Yearly schedules (allow schedules to be applied on an annual basis and be edited and re-applied to a 1 <br />following year). 2 <br /> 3 <br />Provide user-defined "on-off" schedules as specified assignable to an individual HVAC system, 4 <br />subsystem, and/or component. This schedule shall dictate the starting and stopping times, on a daily 5 <br />basis, of the designated systems and components. 6 <br /> 7 <br />Provide user-defined "occupied-unoccupied" schedules as specified above for operation of each fan coil 8 <br />unit, blower coil unit, air-handling unit, ventilation air system, etc. This schedule shall dictate the 9 <br />opening and closing of ventilation air dampers, the starting and stopping of exhaust fans associated 10 <br />with each unit, the operation of make-up air units, etc., on a daily basis, so that ventilation air is 11 <br />provided only during the specific periods during which the area served is occupied. 12 <br /> 13 <br />Temporary override of above schedules shall be allowed by operators with access levels as specified 14 <br />above. A temporary override shall (1) extend hours of use of HVAC systems, subsystems, and/or 15 <br />components up to midnight on weekdays and (2) allow use of HVAC systems, subsystems, and/or 16 <br />components during scheduled "off" periods for a maximum of 12 hours. When an override use period 17 <br />terminates, the temporary override time(s) shall be voided and affected HVAC elements shall return to 18 <br />their normal schedules. 19 <br /> 20 <br />When multiple motors associated with an HVAC are commanded "on" at the same time, the individual 21 <br />DDC start commands shall be staggered by 5 second intervals to second intervals to minimize inrush 22 <br />current. 23 <br /> 24 <br />Alarm Initiation and Response: 25 <br /> 26 <br />All AI points shall have user-defined upper and/or lower condition limits. If user-defined limits are not 27 <br />defined, default limits shall be initially set as follows: 28 <br /> 29 <br />Space temperature 5ºF below low setpoint of comfort zone or 30 <br /> 5ºF above high setpoint of comfort zone 31 <br />Space humidity ≥5% RH above setpoint 32 <br /> 33 <br />Monitor and display "status" (on/off, high/low, open/closed, etc.) of each DI point. Motor on/off status 34 <br />shall be indicated by current sensing relays with field-adjustable trigger point to provide DI "switch", as 35 <br />hereinafter specified. 36 <br /> 37 <br />Monitor and display condition of each AO point (valve or damper percent open, motor speed percent of 38 <br />full speed, etc.) 39 <br /> 40 <br /> 41 <br />CABLING AND WIRING 42 <br /> 43 <br />DDC Cabling: Cabling between buildings shall be fiber optic. Network cabling within buildings shall be 44 <br />shielded twisted pair or fiber optic. Cabling or wiring between control units and I/O point devices shall be as 45 <br />follows: 46 <br /> 47 <br />Application Cable/Wire Type and Min. Gauge (AWG) <br />Digital Input Wiring 24 gauge, twisted pair <br />Analog Input Wiring 24 gauge, shielded twisted pair <br />Digital Output Wiring 24 gauge stranded for 24V <br />18 gauge stranded for 120V <br />Analog Output Wiring 24 gauge, twisted pair <br /> 48 <br />Data Cable: 49 <br /> 50 <br />Twisted shielded cables shall have FFEP insulation in thermoplastic jacket, with #24 AWG stranded 51 <br />conductors, minimum. Shield shall be tinned, soft-copper strands formed into a braid or equivalent foil. 52 <br />Shielding coverage on conductors shall not be less than 100 percent. 53 <br /> 54 <br />DocuSign Envelope ID: 7668B866-6C26-485C-9A45-DAAB5D4BD951