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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 /> 4 <br />1.Provide air differential pressure sensors as indicated in field termination schedules and/or <br />control diagrams. Air differential pressure sensor shall meet,at minimum,the following <br />requirements: <br />a.Sensors used for filter or coil differential pressures shall also have a display of the <br />monitored differential pressure. <br />b.Output shall be 4-20mA,0-10Vdc or 0-5Vdc output proportional to pressure input range <br />compatible with BMS. <br />c.Select range as required,taking into consideration pressure drop across filter or coil. <br />Typically 0-2”wc range for low-pressure commercial duct. <br />d.Operating temperature range of 32°F to 140°F. <br />Q.Differential Pressure Switch –Air <br />1.Provide air differential pressure switches as indicated in field termination schedules and/or <br />control diagrams. Air differential pressure switches shall meet,at minimum,the following <br />requirements: <br />a.An IP54 (NEMA 13)polycarbonate housing. <br />b.SPDT switch rated at 250 Vac at 1 amp. <br />c.Field adjustable range from 0.02”wc to max range of device. Select range as required, <br />taking into consideration pressure drop across filter or coil.Typically 0.2-2”wc range for <br />low-pressure commercial duct. <br />d.Temperature range of -4°F to 140°F. <br />e.Set point adjustment knob with indication. <br />f.Automatic reset. <br />R.Air Flow Measuring Station: <br />1.Provide airflow rate sensors and transducers as indicated in the Field termination schedules <br />and/or control diagrams. Air flow rate sensors and transducer shall meet,at minimum,the <br />following requirements: <br />a.UL 873 listed,BTL listed <br />b.Thermal Dispersion Technology based <br />c.Self-heated sensor:Precision,hermetically sealed,bead-in-glass thermistor <br />d.Temperature sensor:Precision,hermetically sealed,bead-in-glass thermistor <br />e.Sensing Node Housing: <br />1)Material:Glass-filled Polypropylene <br />2)Sensor Potting Materials:Waterproof marine epoxy <br />f.Accuracy:±2%of reading to NIST-traceable airflow standards (includes transmitter <br />uncertainty) <br />g.Calibrated Range:0 to 10,000 fpm <br />h.Accuracy:±0.15 ⁰F to NIST-traceable temperature standards (includes transmitter <br />uncertainty) <br />i.Mounting Rods:Zinc plated steel <br />j.Mouting Brackets:304 stainless steel <br />k.Manufacturer: <br />1)Ebtron <br />2)Or Approved Equal <br />S.Water Pressure Sensor <br />1.Provide water pressure sensors as indicated within the Field termination schedules and/or <br />control diagrams. Pressure sensors shall meet the following requirements: <br />a.Operating range shall be suitable for the application. Select range such that it covers <br />from zero pressure to twice the amount of pressure desired for control purposes or that <br />could be encountered. <br />b.4-20 mA output proportional to water pressure. <br />c.0.25%accuracy of range. <br />d.Temperature range of -40°F to 260°F. <br />e.Over pressure input protection of a minimum two times rated input. <br />DocuSign Envelope ID: 94E7997D-4F29-42F6-A9B4-0A160438D2A6