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Southern Human Services Center Smith Sinnett /2020072 <br />HVAC and Roof Renovations Orange County,North Carolina <br />BAS Sensors and Transmitters 23 09 13.23 - <br /> 5 <br />f.An optional ABS wiring housing is available for an interior application and weatherproof <br />wiring housing is available for an exterior application. <br />g.17-4PH stainless steel wetted parts. <br />h.Burst pressure of a minimum five times rated input. <br />T.Current Relay/Switch <br />1.Provide current sensing relays as indicated in the Field termination schedules and/or control <br />diagrams. Current sensing relays shall meet,at minimum,the following specifications: <br />a.Rated for the applicable load. <br />b.The output relay shall have an accessible trip adjustment over its complete operating <br />range. Provide LED indication of relay status. <br />c.Current relay shall have input and output isolation via current transformer. <br />d.Current relay shall be self-powered with no insertion loss. <br />e.Relay shall be in a dustproof housing. <br />f.Accuracy to be <2%of full-scale max. <br />g.Temperature rating of 5°F to 140°F. <br />h.Whenever the status of a single speed motor is monitored it shall be done via a current <br />sensing relay. <br />i.The BMS contractor shall provide current sensing relays at the MCC starters. <br />j.The BMS contractor shall provide the current sensing relays for motors with local starters <br />and no MCC starter. <br />U.Current Sensor <br />1.Provide monitoring of the current as identified in Field termination sheets and/or control <br />drawings. Current monitoring shall meet,at minimum,the following requirements: <br />a.4-20 mA,0-10 or 0-5 Vdc output proportional to current draw. <br />b.Reverse polarity protected and output limited. <br />c.50/60 Hz operation. <br />d.Accuracy of better than 1%. <br />e.Operating temperature range of -20°F to 120°F. <br />V.Carbon Dioxide (CO2)Sensor <br />1.Provide a space or duct carbon dioxide gas detection sensor as indicated within the field <br />termination schedules and/or control diagrams. Carbon dioxide detection sensors shall meet, <br />at minimum,the following requirements: <br />a.Set-up to be fully microprocessor based c/w LCD. <br />b.4-20 mA,0-10 or 0-5 Vdc output compatible with BMS proportional to 0 to 2000 ppm of <br />carbon dioxide concentration <br />c.Power supply to be 20-28Vac/dc @ 140 mA max for 24 Vac and 80 mA avg.@24 Vdc. <br />d.No maintenance or periodic sensor replacement needed.The sensor shall have a 5-year <br />calibration interval,utilizing the Automatic Calibration Logic Program (ACLP). <br />e.Standard accuracy to be 3%of reading or 75 ppm,whichever is greater. <br />f.Optional integral humidity and temperature transmitter or temperature sensor (thermistor <br />or RTD) <br />g.BACnet communications <br />h.Optional setpoint adjustment,override switch and relay. <br />i.Operating temperature of 32°F to 122°F. <br />PART 3 EXECUTION <br />3.01 INSTALLATION OF SENSORS <br />A.Install sensors according to manufacturer's recommendations. <br />B.Mount sensors rigidly and adequately for operating environment. <br />C.Install room temperature sensors on concealed junction boxes properly supported by wall framing. <br />Box heights shall be coordinated with Division 26 and other trades such that device heights match <br />exactly light switches and other similar control devices. <br />DocuSign Envelope ID: 94E7997D-4F29-42F6-A9B4-0A160438D2A6