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ORANGE COUNTY 230913-3 <br /> <br />Emergency Management Warehouse Building Dehumidification Instrumentation and Control <br /> Devices for HVAC <br /> <br />Damper and Valve Operator/Actuators: Unless indicated otherwise on the Drawings, all actuators shall have fail-safe 1 <br />operation via a mechanical, spring-return mechanism. Provide external, manual gear release on non-spring-return 2 <br />actuators. 3 <br /> 4 <br />Electronic Damper and Valve Operator/Actuator: Shall be direct-coupled type designed for minimum 60,000 5 <br />full-stroke cycles at rated torque. 6 <br /> 7 <br />For valves, size actuator for torque required for valve tight close at pressure hereinbefore specified. 8 <br /> 9 <br />For dampers, size actuator for running torque calculated as follows: 10 <br /> 11 <br />Parallel-Blade Dampers: 7 inch-lb/sq. ft. of damper. 12 <br /> 13 <br />Opposed-Blade Dampers: 5 inch-lb/sq. ft. of damper. 14 <br /> 15 <br />Dampers with Face Velocities exceeding 1000 fpm: Increase running torque by 2.0. 16 <br /> 17 <br />Couplings shall be V-bolt and V-shaped, with toothed cradle. 18 <br /> 19 <br />Provide electronic overload or digital rotation-sensing circuitry. 20 <br /> 21 <br />Actuator shall operate with proportional input signal of 2-10 VDC or 4 to 20 Ma. 22 <br /> 23 <br />Rated temperature operating range for actuators shall be -20 deg F to +120 deg F for conventional 24 <br />applications and -20 to +250 deg F for smoke or fire/smoke damper application. 25 <br /> 26 <br />Actuator full stroke time requirement shall not exceed 12 seconds to open or 5 seconds to 27 <br />close when applied to control smoke dampers or cooling tower bypass valves. 28 <br /> 29 <br />Electric Two-Position Damper Operator/Actuator: Provide a bi-directional, 120-VAC operator with spring 30 <br />return, size actuator for running torque calculated as follows: 31 <br /> 32 <br />Parallel-Blade Dampers: 7 inch-lb/sq. ft. of damper. 33 <br /> 34 <br />Opposed-Blade Dampers: 5 inch-lb/sq. ft. of damper. 35 <br /> 36 <br />Dampers with Face Velocities exceeding 1000 fpm: Increase running torque by 2.0. 37 <br /> 38 <br />Position Indicator: Actuators shall be provided with a compact, adjustable visual position indicator attached 39 <br />to the actuator. As a damper or valve is cycled, the position indicator shall rotate, causing a cylinder to 40 <br />rotate inside a second cylinder with "display windows." When the damper or valve is open, the word "OPEN" 41 <br />shall be displayed in the two windows located 180° apart. When the damper or valve is closed, the word 42 <br />"CLOSED" shall be displayed. Between the two extremes, the display shall be scaled in degrees (0-90). 43 <br /> 44 <br /> 45 <br />PART 3 - EXECUTION 46 <br /> 47 <br /> 48 <br />INSTALLATION 49 <br /> 50 <br />Sensors and Controls: 51 <br /> 52 <br />Permanently mark terminal blocks for identification. Protect all circuits to avoid interruption of service due to 53 <br />short-circuiting or other conditions. Line-protect all wiring that comes from external sources to the site from 54 <br />lightning and static electricity. 55 <br /> 56 <br />Label or code each field wire at each end. Permanently label or code each point of all field terminal strips to 57 <br />show the instrument or item served. Color-coded cable with cable diagrams may be used to accomplish 58 <br />cable identification. 59 <br /> 60 <br />DocuSign Envelope ID: 7668B866-6C26-485C-9A45-DAAB5D4BD951