DARTMOUTH COLLEGE DESIGN January 3, 2012 & CONSTRUCTION GUIDELINES

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1 PART DESIGN DIRECTIVE. QUALITY ASSURANCE SECTION 530 METERS AND GAGES A. Comply with applicable UL standards pertaining to meters and gages and with applicable portions of ASME and Instrument Society of America (ISA) standards pertaining to construction and installation of meters and gages..2 DESIGN CRITERIA A. The designer shall indicate on the drawing details and flow schematics the locations of all gauges. B. At hydronic pumps a single pressure gauge shall be installed with isolated taps before the strainer, between the strainer and the pump inlet, and after the pump discharge. This is not required at domestic hot water recirculation pumps. C. Every main shall have a minimum of one pressure gauge and one temperature gauge for every section of pipe between isolation valves. D. Every major device where the temperature can change shall be equipped with a temperature gauge and pressure gauge on both the inlet and discharge piping connections. E. Provide low pressure drop flow meters on piping systems served by pumps equipped with variable frequency drives. PART 2 PRODUCTS 2. THERMOMETERS, GENERAL A. Accuracy shall be % of range span, grade A. B. Temperature ranges for services listed as follows (center of range shall be the scheduled fluid temperature):. Domestic Hot Water: 0 to 200 F with 2 scale divisions. 2. Domestic Cold Water: 30 to 30 F with 2 scale divisions. 3. Hot Water: 0 to 250 F with 2 scale divisions. 4. Condenser Water: 0 to 200 F with 2 scale divisions. 5. Chilled Water: 30 to 30 F with 2 scale divisions. 6. Steam and Condensate: 50 to 300 F with 2 scale divisions. 2.2 BIMETAL DIAL THERMOMETERS A. Direct mounted, bimetal type with adjustable angle feature for 360 rotation and 80 angle adjustment. Hermetically sealed, 5" diameter case of welded stainless steel construction with external adjustment. Thermometer shall have a bimetal coil, plastic window, white dial with black markings. Stem Length of 6", or adjust length to be minimum 3" from insulation, /2" NPT stem connection. 530-METERS & GAGES Page of 7

2 B. Manufacturers:. Ashcroft, Dresser Industries, Instrument Div. #50EL60E series. 2. Trerice #B85600 series 2.3 THERMOMETER WELLS A. Brass threaded thermometer wells for all piping systems, pressure rated to match piping system design pressure; with 2" extension for insulated piping and threaded cap nut with chain permanently (material to match well material) fastened to well and cap. 2.4 PRESSURE GAGES A. General use, ASME B40., Grade 2A, phosphor bronze bourdon tube type, bottom connection. Phenolic case, 4-/2" diameter, with /2" NPS brass connector. White coated aluminum background, with permanently etched black markings. Accuracy shall be /2% of range span. The scale range for all gages shall be 2 times the operating pressure. All gages in liquid systems shall be vibration resistant (Plus performance or silicone filled). B. Manufacturers:. Ashcroft, Dresser Industries, Instrument Div. a. Steam systems: # L b. Liquid systems: # L-XLL 2. Trerice a. Steam systems: #450B45TRL500PSI series b. Liquid systems: #450BG45TRL500PSI series 2.5 TEST PLUGS A. Test Plugs shall be nickel plated brass body, with ¼ or ½" NPS fitting and two self sealing valve type core inserts, suitable for inserting a probe assembly from a dial type thermometer or pressure gage. Test plug shall have gasketed and threaded cap with retention chain and body of length to extend beyond insulation. Pressure rating shall be 500 psig. B. Core Material: Conform to the following for fluid and temperature range:. -30 F to 275 F: EPDM. C. Manufacturers:. MG Piping Products Co. 2. Peterson Equipment Co., Inc. 3. Sisco, A Spedco, Inc. Co. 4. Trerice (H.O.) Co. 5. Watts Regulator Co. 2.6 PRESSURE GAGE ACCESSORIES A. Connectors:. Steam systems: Provide /2" NPS iron pig tail siphons. 2. Water systems, steel: /2" NPS steel (for steel pipe) or brass (for copper pipe) nipple, length to allow minimum 3" beyond insulation cover. B. Snubber. Steel piping systems: /2" stainless steel, Ashcroft #2S, or Ashcroft #2B, /2" brass, for copper piping systems 530-METERS & GAGES Page 2 of 7

3 2. Provide a /2" ball or needle valve, carbon steel for steel piping systems or bronze for copper piping systems. 2.7 STEAM CONDENSATE METERS A. Gravity type and pressure type condensate meters shall constructed of a metal housing with a volumetric measuring drum and a self powered totalizer. Casing shall be cast iron with a copper metering drum. System shall be designed for operating temperature of 350 at 00% humidity.be:. ACCURACY: +/- 0.25% or better of the reading for liquids. Power supply 00 to 250 VAC, 60hz. 2. RANGEABILITY: 300: turn down or better. 3. COMMUNICATION: Modbus/TCP 4. Liner material (Teflon) rated to 250 degree F. 5. Factory Mutual Approved. Electronics can be integral or remote..6. Gravity type condensate meter shall be a Cadillac Magnetic flow-meter CMAG Series manufactured by Central Station Steam Co., Tigard, OR Cadillac Condensate Meters as manufactured by Claussen Engineering, Camas WA B. Pressure type condensate meters shall be a brass housing with an internal impeller capable of withstanding hot temperatures (220 F). The meter shall be self-powered not requiring power from an external source and have a self contained gauge. Provide a pulse output for remote meter reading. Supply input 24VDC max, current requirement 30Ma.. Niagra series MTX, model 42, with model 860 infrared pulser model 840 reed switch output. 2.8 ULTRASONIC FLOW/ENERGY METERS A. The ultrasonic flow-energy meter shall be a clamp-on, dual channel transit-time design precluding the requirement of penetrating into the pipe. The dual channel operating mode shall be capable of acting as an energy meter using two strap on temperature sensors and a flow meter. The unit shall be able to calculate and display chilled water use in ton-hours. The flowmeterflow/energy meter shall be completely microprocessor based. The flowmeterflow/energy meter shall employ technology to insure operation on liquids with solids and or bubbles. B. The flowmeterflow/energy meter shall provide automatic transducer spacing utilizing a mounting track (ruler scales not acceptable).. The flowmeterflow/energy meter shall have the ability to indicate flow & energy rate, flow velocity, total energy, T, T2 & delta T, signal strength for both channels or paths. The flowmeterflow/energy meter shall be equipped with an integral front panel keypad and multifunction display with the ability of displaying both channels and paths simultaneously. In addition, the flowmeterflow/energy meter shall provide self and application diagnostics to isolate any fault conditions to either equipment failure or abnormal process conditions. The flowmeterflow/energy meter shall have full HELP menu routines corresponding to all levels of programming and operation. C. The flow-energy meter electronics shall be housed in a NEMA 4X enclosure and powered by 5VAC, 60Hz. One isolated 4 to 20 madc and one 0 to 5000 Hz pulse output proportional to flow shall be provided for each channel or the average of both paths. In addition,the flow/energy meter shall employ using an open communications protocol such as Lon Works, Modbus TCP, or BACnet. tthe unit shall provide one 0 to 0 volt or 4-20mA output and four alarm relays assignable to flow velocity, liquid sonic velocity, signal strength or liquid aeration. An internal datalogger shall be provided to 530-METERS & GAGES Page 3 of 7

4 allow storage of all measured and calculated variables and alarms. A bi-directional RS- 232 connection shall be provided to allow remote programming and interrogation. D. The flow-energy meter shall have an accuracy of +/-% of flow over a +/-40 fps flow range. Repeatability shall be 0.% of flow with a flow sensitivity of 0.00 fps at any flow rate including no flow conditions. Turndown shall be at least :200. E. By use of either transit-time or Doppler modes of operation, the flowmeterflow/energy meter shall be capable of measuring all liquids in full sonically conductive pipes. FlowmeterFlow/energy meters that simply offer stand alone transit-time or Doppler measurement modes are not acceptable. The flow meters shall be able to be used on steel pipes up to schedule 80 and PVC pipes up to sch 80 thickness. F. Supply and return temperature measurement shall be via platinum matched RTD S mounted in a thermowell. G. Energy calculation shall be integral to the meter and shall utilize the feed temperature for mass calculation. H. FlowmeterUltrasonic Flow/energy meters shall be:. GE Sensing, GE Infrastructure Sensing Inc., Model: DF Controlotron model 00EDN 2. Panametrics model AT MAGNETIC FLOW/ENERGY METERS A. The magnetic flow meter is inserted in the pipe system and is constructed of 304 stainless steel having the following characteristics:. Single channel, Outputs: 4-20mADC and pulse digital I/O 2. ACCURACY: +/- 0.25% or better of the reading for liquids. 3. RANGEABILITY: 300: turn down or better. 4. COMMUNICATION: Modbus/TCP 5. Liner material (Teflon) rated to 250 degree F. 6. Factory Mutual Approved. Electronics can be integral or remote. 7. Cadillac Magnetic Energy/flow-meter series CMAG/HEATX Hot/Chilled Water Energy Meter manufactured by Central Station Steam Co., Tigard, OR LOW PRESSURE DROP FLOW METERS A. Pitot tube type design sensing upstream total pressure and downstream static pressure. Meter shall have very low pressure drop.. Bell & Gossett Circuit Sensor 2. Taco Sentinel PART 3 EXECUTION 3. THERMOMETERS INSTALLATION A. Install thermometers in vertical and tilted positions to allow reading by observer standing on floor. B. Install thermometer wells in piping tee where thermometers are indicated, in vertical position. Fill well with oil or graphite and secure cap. 530-METERS & GAGES Page 4 of 7

5 3.2 INSTALLATION OF PRESSURE GAGES A. Install pressure gages in piping tee with pressure gage valve, located on pipe at most readable position. B. Install snubbers in liquid piping systems, siphons in steam piping systems. 3.3 CONNECTIONS A. Install meters and gages piping adjacent to machine to allow servicing and maintaining of machine. B. Install test plugs in stems of all thermometers and pressure gages. 3.4 CONDENSATE METERS A. Install gravity type meters in systems that do not have condensate pumps. B. Install pressure type meters in systems with condensate pumps. All meters must be able to be read directly with or without the use of a ladder. Where meters are not readable from the floor provide a floor level remote display. C. All condensate meters shall have a full port valved bypass valve with lock handle and full port isolation valves. Meters shall be piped so that there is a column of liquid present in the meter at all times. D. Install all meters in conformance with manufacturer s written instructions with particular attention paid to pipe configuration. 530-METERS & GAGES Page 5 of 7

6 E. Typical Meter Installation: Dartmouth College Condensate Meter Connection Standards Rev..0 January, 20 Note: All wiring to be in conduit Pulse Output to Wireless Transmitter. (Typical = 0 Gallons per Pulse) Condensate return to Central Heating Plant Check valve on leaving side of meter (for protection of meter) Bypass Line Provide Model 840 reed switch for pulse output Provide additional Model 840 reed switch and remote readout if meter register cannot be read from the floor in an accessible position. Niagara Condensate Meter (MTX Model 42 or WPX Model 20) by Per Dartmouth Standards, Specification, and Approved Submittals to provide a pair of wires from meter to building electric vault Condensate Receiver Duplex Condensate Pump Set Meter Output Points: (See meter, above) Condensate consumption pulse output (via reed switch to wireless pulse transmitter) C. Materials and Labor by (s) 3.5 ULTRASONIC FLOW/ENERGY METERS A. Install ultrasonic flow meters in chilled water systems at building entrancesonly. A.B. Install all meters in conformance with manufacturer s written instructions with particular attention paid to pipe configuration. 530-METERS & GAGES Page 6 of 7

7 C. Typical flow/energy meter installation: Dartmouth College Chilled Water Energy Meter Connection Standards Rev..0 January, 20 Thermowell by RTD Wiring per Mfg s recommendations Ultrasonic Transducer by (Typ of 2) Supply Line Thermowell by RTD 4 Wire Precision Matched Platinum RTDs by Note: Maintain Mfgr s recommended upstream and downstream dimensions for ultrasonic transducers in relation to turns and obstructions Stainless Steel Straps Return Line Energy Meter by Per Dartmouth Standards, Specification, and Approved Submittals Note: All wiring to be in conduit Energy Totalizer Pulse Output to Wireless Transmitter. Scaling to be set in software in Energy Meter (Typical = 0 Ton-Hrs per Pulse) Modbus / TCP, Data jack Supplied by the Meter Output Points: (See meter, above) Output Points from Energy Meter to BMS By Energy Totalizer Pulse Output (Typ. 0 Ton-Hrs/Pulse) Instantaneous Energy Rate (Tons) Out to BMS (4-20 ma) Instantaneous Flow Rate (GPM) Out to BMS(4-20 ma) Meter Common Alarm Out to BMS (DO) Separate 20 VAC, 5A, Control Power Circuit by Materials and Labor by (s) 3.6 MAGNETIC FLOW/ENERGY METERS A. Install all meters in conformance with manufacturer s written instructions LOW PRESSURE DROP FLOW METERS A. Comply with manufacturer's written recommendations for unrestricted pipe upstream and downstream of the meter. END OF SECTION METERS & GAGES Page 7 of 7