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Orange County West Campus Office Building -HVAC <br />PDC Project 23020 BAS DIRECT DIGITAL CONTROL <br />SYSTEM 23 09 02 - 6 <br />e.Accuracy at calibration point +/-1.0 F <br />C.Humidity transmitters <br />1.Outside/Duct/Room Humidity Transmitters <br />a.Sensor humidity range 0%to 100%RH <br />b.Accuracy 2% <br />D.Differential Pressure Switches (Air) <br />1.Differential pressure switches shall be diaphragm operated with SPDT snap action switch <br />with adjustable differential pressure range 8 to 70 psig. Maximum allowable differential <br />bellows shall be 200 psig,maximum allowable pressure shall be 325 psig. <br />2.Contact shall be rated at 120 volts,15 amps AC <br />E.Relays <br />1.Control relays shall be UL listed plug-in type with dust cover and LED “energized”indicator. <br />Contact rating,configuration,and coil voltage shall be suitable for application. <br />2.Time delay relays shall be UL listed solid-state plug-in type with adjustable time delay.Delay <br />shall be adjustable ±200%(minimum)from set point shown on plans.Contact rating, <br />configuration,and coil voltage shall be suitable for application.Provide NEMA 1 enclosure <br />when not installed in local control panel. <br />F.Override timers <br />1.Override timers shall be spring-wound line voltage,UL Listed,with contact rating and <br />configuration as required by application.Provide 0-to-6-hour calibrated dial unless otherwise <br />specified.Timer shall be suitable for flush mounting on control panel face and located on <br />local control panels or where shown. <br />G.Current transmitters. <br />1.AC current transmitters shall be the self-powered,combination split-core current transformer <br />type with built-in rectifier and high-gain servo amplifier with 4 to 20 mA two-wire output.Unit <br />ranges shall be 10 A,20 A,50 A,100 A,150 A,and 200 A full scale,with internal zero and <br />span adjustment and ±1%full-scale accuracy at 500 ohm maximum burden. <br />2.Transmitter shall meet or exceed ANSI/ISA S50.1 requirements and shall be UL/CSA <br />Recognized. <br />3.Unit shall be split-core type for clamp-on installation on existing wiring. <br />4.Current transformers <br />5.AC current transformers shall be UL/CSA Recognized and completely encased (except for <br />terminals)in approved plastic material. <br />6.Transformers shall be available in various current ratios and shall be selected for ±1% <br />accuracy at 5 A full-scale output. <br />7.Transformers shall be fixed-core or split-core type for installation on new or existing wiring, <br />respectively. <br />H.Voltage transmitters <br />1.AC voltage transmitters shall be self-powered single-loop (two-wire)type,4 to 20 mA output <br />with zero and span adjustment. <br />2.2 Ranges shall include 100 to 130 VAC,200 to 250 VAC,250 to 330 VAC,and 400 to 600 <br />VAC full-scale,adjustable,with ±1%full-scale accuracy with 500 ohm maximum burden. <br />3.Transmitters shall be UL/CSA Recognized at 600 VAC rating and meet or exceed ANSI/ISA <br />S50.1 requirements. <br />I.Voltage transformers <br />1.AC voltage transformers shall be UL/CSA Recognized,600 VAC rated,complete with built-in <br />fuse protection. <br />2.Transformers shall be suitable for ambient temperatures of 4°C to 55°C (40°F to 130°F)and <br />shall provide ±0.5%accuracy at 24 VAC and a 5 VA load. <br />3.Windings (except for terminals)shall be completely enclosed with metal or plastic material. <br />J.Power monitors <br />Docusign Envelope ID: 8DED1454-68D2-4E36-9FC6-E56FF2124E5D