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ORANGE COUNTY 230923-7 <br /> <br />Emergency Management Warehouse Building Dehumidification Extension of Existing Direct Digital <br /> Control System for HVAC <br /> <br />Remote communications. 1 <br /> 2 <br />Maintenance management. 3 <br /> 4 <br />Units of Measure: Inch-pound. 5 <br /> 6 <br />Local operator interface to provide for download from or upload to operator workstation or diagnostic 7 <br />terminal unit. 8 <br /> 9 <br />Control Modes: Control loops shall be able to utilize any of the following control modes: 10 <br /> 11 <br />Two position (e.g., on-off, slow-fast) 12 <br /> 13 <br />Proportional (P), proportional plus integral (PI), or roportional plus integral plus derivative (PID), applied 14 <br />as follows: 15 <br /> 16 <br />Controlled Variable Control Mode <br />Space Temperature P <br />Humidity P (PI throttling range is less than 5%) <br /> 17 <br />For any unlisted application, the control mode shall be as approved by the A-E. 18 <br /> 19 <br />I/O Interface: Hardwired inputs and outputs may tie into system through controllers. Protect points so that 20 <br />shorting will cause no damage to controllers. 21 <br /> 22 <br />Digital (Binary) Inputs: Allow monitoring of on-off signals without external power. 23 <br /> 24 <br />Pulse Accumulation Inputs: Accept up to 10 pulses per second. 25 <br /> 26 <br />Analog Inputs: Allow monitoring of low-voltage (0- to 10-V dc), current (4 to 20 mA), or resistance 27 <br />signals. 28 <br /> 29 <br />Digital (Binary) Outputs: Provide on-off or pulsed low-voltage signal, selectable for normally open or 30 <br />normally closed operation with three-position (on-off-auto) override switches and status lights. 31 <br /> 32 <br />Analog Outputs: Provide modulating signal, either low voltage (0- to 10-V dc) or current (4 to 20 33 <br />mA) with status lights, two-position (auto-manual) switch, and manually adjustable potentiometer. 34 <br /> 35 <br />Tri-State Outputs: Provide two coordinated binary outputs for control of three-point, floating-type 36 <br />electronic actuators. 37 <br /> 38 <br />Universal I/Os: Provide software selectable binary or analog outputs. 39 <br /> 40 <br />Power Supplies: Transformers with Class 2 current-limiting type or overcurrent protection; limit connected loads 41 <br />to 80 percent of rated capacity. DC power supply shall match output current and voltage requirements and be 42 <br />full-wave rectifier type with the following: 43 <br /> 44 <br />Output ripple of 5.0 mV maximum peak to peak. 45 <br /> 46 <br />Combined 1 percent line and load regulation with 100-mic.sec. response time for 50 percent load 47 <br />changes. 48 <br /> 49 <br />Built-in over-voltage and over-current protection and be able to withstand 150 percent overload for at 50 <br />least 3 seconds without failure. 51 <br /> 52 <br />Power Line Filtering: Internal or external transient voltage and surge suppression for workstations or controllers 53 <br />with the following: 54 <br /> 55 <br />Minimum dielectric strength of 1000 V. 56 <br /> 57 <br />DocuSign Envelope ID: 7668B866-6C26-485C-9A45-DAAB5D4BD951