1、Designation: E 929 83 (Reapproved 2005)Standard Test Method forMeasuring Electrical Energy Requirements of ProcessingEquipment1This standard is issued under the fixed designation E 929; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisio
2、n, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of the energyand power requirements of processing equipment
3、using anelectrical metering system.1.2 This test method can be used to measure energy andpower requirements of processing equipment driven by anelectrical motor operating on alternating current.1.3 This test method includes instructions for installationand checkout of the energy metering system, pro
4、cedures formeasuring and recording energy usage, and methods forcalculating the average gross power, average freewheelingpower, and average net power requirements of processingequipment.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is th
5、eresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. For hazard state-ments, see Section 6.2. Terminology Definitions2.1 electrical metering systema system composed of cur-rent and
6、potential transformers and a wattmeter electricallyconnected in such a manner so as to measure the energy usageof a piece of equipment driven by an electric motor.2.2 freewheeling conditiona piece of equipment under anunloaded condition wherein the electrical energy is dissipateddue to friction and
7、windage.2.3 freewheeling powerpower requirement of a piece ofequipment under unloaded, or freewheeling, conditions.2.4 gross energy energy usage of a piece of equipmentoperating under loaded conditions as measured using anelectrical metering system.2.5 gross power power requirement of a piece of equ
8、ip-ment under loaded conditions.2.6 loaded condition equipment doing processing workon solids, liquids, or gases, or all of these, (for example,moving material, changing its characteristics, or separating itinto different streams).2.7 net powerthe difference between gross power andfreewheeling power
9、; net power is the power required forprocessing.2.8 specific energy energy consumption expressed on thebasis of unit mass of throughput.2.9 unloaded conditionequipment not doing processingwork (for example, moving, changing the characteristics of, orseparating materials), but operating in a freewhee
10、ling, oridling, condition.3. Summary of Test Method3.1 An electrical metering system is installed and checked.3.2 The metering instrumentation and processing equipmentis allowed to warmup.3.3 Using the electrical metering system, the energy used bythe processing equipment under no-load and loaded co
11、nditionsis measured and recorded.3.4 The average gross power, average freewheeling power,and average net power required by the equipment is calculated.4. Significance and Use4.1 Energy usage and power requirements of processingequipment are important from the standpoint of determining ifequipment is
12、 operating within specification and meeting per-formance criteria.4.2 Having determined the energy usage and power require-ments of the processing equipment using this method, specificenergy may be calculated, with the use of system throughput,and used as one criterion to compare the performance ofs
13、imilar pieces of equipment operating under similar operatingconditions.4.3 Measurements of energy usage can be used for thepurpose of identifying inefficient electrical motors and process-ing equipment.5. Apparatus5.1 Calibrated Watthour Meter.5.2 Volt-Ammeter.5.3 Stopwatch, accurate to 0.1 s.5.4 In
14、candescent Lamps, for use as a known load.5.5 Current Transformers (CTs).1This test method is under the jurisdiction of ASTM Committee D34 on WasteManagement and is the direct responsibility of Subcommittee D34.06 on Recoveryand Reuse.Current edition approved Feb. 1, 2005. Published March 2005. Orig
15、inallyapproved in 1983. Last previous edition approved in 1999 as E 929-83(1999).1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.6 Potential (Voltage) Transformers (PTs).6. Hazards6.1 When installing metering equipment always de-en
16、ergizethe load side of the processing equipment by locking out themain switch on the electrical control panel.6.2 Dangerous high voltage results from open current trans-former secondaries. Therefore, to avoid equipment damage andelectrical shock, use circuit-closing devices or equipment toshort circ
17、uit the secondaries of current transformers.6.3 Always observe the polarity markings of current andpotential transformers during their installations to ensureproper connection of the metering equipment. These polaritymarkings are usually denoted on the transformers as whitedots, blocks, or “HX” mark
18、s.6.4 Closely observe polarities, and check connections ofinstrument transformers to the watthour meter.7. Equipment Calibration7.1 Calibrate all meters and instrument transformers usedfor energy measurements in accordance with standard practiceof calibration.2,3,4,5The accuracy of the meters and tr
19、ansformers shall be duly noted on the Electrical Metering ServiceInstallation Form, see Fig. 1.8. Procedure8.1 Meter Installation:8.1.1 For the piece of equipment to be tested, determine thetype of electrical service (for example, single-phase two-wire,three-phase three-wire), voltage requirements,
20、full load power,and current rating of the motor from the motor nameplate ormanufacturers specifications. For the purpose of meter selec-tion and installation, it can be assumed that 1 hp = 1 kW = 1kVA. Select the metering system that is compatible with thetype of electrical service and with the load
21、 on the motor.8.1.1.1 Self-contained single phase watthour meter can beused when the load is less than 48 kVA.8.1.1.2 Self-contained polyphase meters can be used whenthe load is less than 96 kVA (except 480 V delta).8.1.1.3 Above 48 or 96 kVA, respectively, for single andpolyphase loads, use transfo
22、rmer type watthour meters.8.1.2 For any meter installation, do not exceed the metersoverload capability listed as follows:8.1.2.1 Class 10Nominal 2.5-A meter, 10-A overloadcapability.8.1.2.2 Class 20Nominal 2.5-A meter, 20-A overloadcapability.8.1.2.3 Class 60Nominal 15-A meter, 60-A overloadcapabil
23、ity.8.1.2.4 Class 100Nominal 15-A meter, 100-A overloadcapability.8.1.2.5 Class 200Nominal 30-A meter, 200-A overloadcapability.8.1.2.6 Class 320Nominal 50-A meter, 320-A overloadcapability.8.1.3 Instrument TransformersFor meter installations re-quiring instrument transformers (that is, when the pri
24、marycurrent or voltage, or both, exceed the operating specificationsof the watthour meter), use current and potential (voltage)transformers. Select current and potential transformers with anaccuracy class rating of 0.3 (0.3 %) and compatibility with theprimary electrical service. If transformers wit
25、h an accuracyclass of 0.3 are not available, substitute another accuracy classand note on the Electrical Metering System Installation Form(Fig. 1).8.1.4 Current TransformersCalculate the current trans-former ratio (CTR) using the following definition.CTR 5 Primary Current/Watthour Meter Nominal Curr
26、ent Rating(1)Generally, current transformer ratios are denoted such thatthe secondary current will be 5 amperes when rated amperesare flowing in the primary circuit.8.1.5 Potential Transformers Potential transformers areused with watthour meters where the primary circuit voltageexceeds the rating of
27、 the meter, generally above 480 V andfrequently above 240 V. The potential transformer ratio (PTR)can be calculated using the following definition.2Meter and Instrument Transformer Application Guide, 5th Edition, Westing-house Electric Company, Raleigh, NC.3Metermens Handbook, Duncan Electric Compan
28、y, Lafayette, IN, No. 5M,April 1976.4Electrical Metermens Handbook, Edison Electric Institute, New York, NY.5Guide for Installing General Electric Watthour Meters, General ElectricCompany, Somersworth, NH, April 1976.Watthour Meter Serial No. Type Class KhAccuracy Date CalibratedCurrent Transformer
29、Serial No. Type Ratio Accuracy Class Date CalibratedPotential Transformer Serial No. Type Ratio Accuracy Class Date CalibratedFIG. 1 Electrical Metering System Installation FormE 929 83 (2005)2PTR 5 Primary Voltage/Watthour Meter Nominal Voltage Rating(2)8.1.6 Phase relations will be retained if the
30、 polarity mark-ings are observed and the current in the potential circuit isconsidered to flow in on the primary terminal polarity mark andout on the corresponding secondary terminal polarity mark.8.1.7 The Electrical Metering Service Installation Form(Fig. 1) is recommended for documenting the equi
31、pment usedfor the test.8.1.8 Mount instrument transformers and watthour metersin an upright position and in a area free from heavy vibration.8.2 Checking Meter Installation:8.2.1 Check meter installations for correct connections assoon as the wiring is completed. For installation of self-contained w
32、atthour meters this is comparatively simple. It isonly necessary to see that line and load wires, and potentialtaps where required, are connected to the proper points. Aquick check on the operation under load conditions may bemade to see that the meter is rotating in the proper directionand at appro
33、ximately the right speed.8.2.2 Where instrument transformers are used, the installa-tion is more liable to incorrect connections and should,therefore, be checked carefully. It is possible to have incorrectregistration even with proper connections, due to a wrongtransformer polarity marking, a revers
34、ed meter coil, incorrecttransformer ratio marking, etc. It is generally not possible tocompletely check all of these items in the field; however, bymaking several of the tests listed in Annex A1, it will bepossible to determine most of the inconsistencies or incorrectconnections that might occur.8.3
35、 Measurements:8.3.1 After installation and check-out of the energy meter-ing equipment, measure and record the energy used by theequipment under no-load and loaded conditions in order todetermine the average gross and freewheel power requirementsof the equipment.8.3.2 Determine the average freewheel
36、ing power of theequipment to be tested by measuring the energy usage of themotor under no-load conditions over a specified time interval.After a suitable warm-up period, time ten disk revolutions toestablish the freewheel energy usage at the beginning and endof the test. Prior to taking the first me
37、asurement for determin-ing the freewheel energy usage, take two preliminary free-wheel energy measurements (10 disk revolutions) approxi-mately 5 min apart. If the preliminary readings differ by morethan 10 % or more, extend the warm-up period until twoconsecutive preliminary measurements fall withi
38、n 10 % of oneanother.8.3.3 After the suitable warm-up period, take and recordthree initial disk timings of ten revolutions each. Likewise,after the conclusion of the load tests, take and record three finaldisk timings of ten revolutions each. An Energy MeasurementData Sheet for recording the freewhe
39、eling energy measure-ments is given in Fig. 2. The freewheeling power calculationsare described in Section 9.8.3.4 Determine the gross energy usage ( Eg) of the equip-ment undergoing testing by calculating the difference in theregister readings or by counting the number of disk revolutionsof the wat
40、thour meter while operating the processing equip-ment under loaded conditions for a suitable measuring period.A suitable measuring period consists of a time span that is longenough to attain at least one disk revolution or at least onecomplete rotation of the least significant register dial, which-e
41、ver applies to the particular test situation.8.3.5 An Energy Measurement Data Sheet for recording themeasured data from the tests conducted under loaded condi-tions is given in Fig. 2. The calculations for determining powerdemand under loaded conditions are described in Section 9.8.3.6 Alternative P
42、rocedure for Constant Load PowerMeasurementsIf the processing equipment exhibits a con-stant load as evidenced by power fluctuations of less than610 % of the average reading (that is, as may be the case fora conveyor or blower, etc.), a clamp-on wattmeter, an analogwattmeter, or recording wattmeter
43、can be used to measurepower if the metering equipment and electrical service can bemade compatible with one another. For this procedure, powermeasurements for both unloaded (freewheeling) and loadedconditions should be made in sufficient numbers so that areliable average reading can be calculated. T
44、he power require-ment is read directly from the instrument. The measurementsmay be recorded on the Gross and Net Power Data Sheet, Fig.3.9. Calculation9.1 Average Freewheeling Power Requirements:9.1.1 Calculate freewheeling power ( Pfw), in kilowatts, asfollows:Pfw5 600 Kh!CTR!PTR!/t (3)where:Kh = d
45、isk constant of the watthour meter (kWh/diskrevolution),CTR = current transformer ratio,PTR = potential transformer ratio, andt = time duration for 10 disk revolutions (minutes).9.1.2 Average the three initial freewheeling power measure-ments and the three final measurements to give the averageiniti
46、al freewheeling power ( Pfwi) and final freewheeling power( Pfwf). Then average the average values ( Pfwiand Pfwf) and useas the average freewheeling power requirement Pfwof theequipment corresponding to the interval of gross energymeasurement. Record the average value for the freewheelingpower in t
47、he column titled “Average Freewheel Power” of theGross and Net Power Data Sheet (see Fig. 3).9.1.3 Calculate average initial freewheel power ( Pfwi)asfollows:Pfwi5 Pfwa1 Pfwb1 Pfwc!/3 (4)where:Pfwa,Pfwb, and Pfwcare the three initial freewheeling powermeasurements.9.1.4 Calculate average final freew
48、heel power ( Pfwf)asfollows:Pfwf5 Pfwx1 Pfwy1 Pfwz!/3 (5)E 929 83 (2005)3where:Pfwx, Pfwy, and Pfwzare the three final freewheeling powermeasurements.9.1.5 Calculate average freewheel power as follows:Pfw5 Pfwi1 Pfwf!/2 (6)9.2 Determine the gross energy ( Eg) usage of the equipmentundergoing testing
49、 by calculating the difference in the registerreadings (Case 1) or by counting the number of disk revolu-tions of the watthour meter after a suitable measuring period(Case 2).9.2.1 For Case 1, calculate the gross energy ( Eg) as follows:Eg5 Rf2 Ri!PTR!CTR! (7)where:Rf= final meter reading (kWh),Ri= initial meter reading (kWh),PTR = potential transformer ratio, andCTR = current transformer ratio.9.2.2 For Case 2, calculate the gross energy ( Eg) as follows:Eg5 60 n Kh!PTR!CTR!/t (8)where:n = number of disk revolutions (rev.),Kh = disk con
