1、Designation: F 2044 00An American National StandardStandard Specification forLiquid Level Indicating Equipment, Electrical1This standard is issued under the fixed designation F 2044; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、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 specification covers the requirements for electricalliquid level indicating equipment for shipboard
3、low pressureand high pressure tanks containing freshwater, feed water,potable water, seawater, wastewater, diesel fuel, lubricating oil,contaminated oil, refrigerants, JP fuels, and various otherfluids. Application includes compensating tanks in which theequipment must locate the interface.1.2 Each
4、liquid level indicating equipment typically consistsof the following components:(a) One or more sensing devices;(b) Flexible interconnections, if needed;(c) Primary indicator panel assembly;(d) Auxiliary indicator panel assembly, when required; and(e) Portable indicator panel assembly, when required
5、.1.3 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly. Where information is to be specified, it shall be stated inSI units.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use.
6、 It is theresponsibility 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.1.5 Special requirements for naval shipboard applicationsare included in the Supplement to this standard.2. Referenced D
7、ocuments2.1 ASTM Standards:D 3951 Practice for Commercial Packaging22.2 ISO Standards:9001 Quality System Model for Quality Assurance inDesign/Development, Production, Installation, and Ser-vicing33. Terminology3.1 Definitions:3.1.1 hysteresismaximum difference in output, at anymeasurand value withi
8、n the specified range, when the value isapproached first with increasing and then with decreasingmeasurand.3.1.2 insulation resistancethe resistance measured be-tween insulated portions of a liquid level indicating equipmentand between insulated portions of a liquid level indicatingequipment and gro
9、und when a specified dc voltage is appliedunder specified conditions.3.1.3 outputelectrical or numerical quantity, produced bya liquid level indicating sensor or measurement system, that isa function of the applied measurand.3.1.4 pressure cyclingthe specified minimum number ofspecified periodic pre
10、ssure changes over which a liquid levelindicating sensor will operate and meet the specified perfor-mance.3.1.5 process mediumthe measured fluid (measurand) thatcomes in contact with the sensing element.3.1.6 repeatabilityability of a liquid level indicatingequipment to reproduce output readings whe
11、n the same mea-surand value is applied to it consecutively, under the sameconditions, and in the same direction.3.1.7 responsethe measured output of a liquid level indi-cating sensor to a specified change in measurand.3.1.8 signal conditioneran electronic device that makesthe output signal from a se
12、nsor element compatible with areadout system.3.1.9 wetted partsliquid level indicating equipment com-ponents with at least one surface in direct contact with theprocess medium.4. Designation4.1 DesignationMost liquid level indicating equipmentmanufacturers use designations or systematic numbering or
13、identifying codes.4.2 DesignLiquid level indicating equipment typicallyconsist of a sensing device that may or may not be in contactwith the process medium, a transduction element that modifiesthe signal from the sensing device to produce an electricaloutput, and an indicator panel assembly to show
14、the level of themedium being measured. Some parts of the sensing device maybe hermetically sealed if those parts are sensitive to and may beexposed to moisture. The output cable must be securelyfastened to the body of the sensing device. A variety of sensing1This specification is under the jurisdict
15、ion of ASTM Committee F-25 on Shipsand Marine Technology and is the direct responsibility of Subcommittee F25.10 onElectrical and Electronics.Current edition approved July 10, 2000. Published September 2000.2Available from the Annual Book of ASTM Standards, Vol 15.09.3Available from American Nationa
16、l Standards Institute, 11 W. 42nd St., 13thFloor, New York, NY 10036.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.devices is used in liquid level indicating equipment. In themost common types of devices, sensing techniques such as
17、admittance/impedance, magnetic float, static pressure, differ-ential pressure, time domain reflectometry, radar, capacitive,resistance tape-type and ultrasonic are used. The function ofthe sensing device is to produce a measurable response to theadmittance, impedance, differential pressure, reflecte
18、d energy,capacitance, or resistance of the fluid being measured. Thefollowing is a brief introduction to the major level sensingtechnology design categories.4.2.1 Sensing TechniquesThe sensing device typicallydoes not use any part of the tank structure as part of the sensingdevice.4.2.1.1 Admittance
19、 and ImpedanceThe admittance andimpedance sensing technique uses the apparent resistance tothe current flow of an alternating current in the sensing devicecircuit or its reciprocal with respect to the level of the measuredfluid in the tank.4.2.1.2 Magnetic FloatThe magnetic float sensing tech-nique
20、uses a float with embedded magnets to change the circuitstatus of the sensing device and produce an electrical signalproportional to the floats position with respect to the level ofthe measured fluid in the tank.4.2.1.3 Differential PressureThe differential pressure-sensing technique uses the pressu
21、re difference regardless of theambient pressure to change the circuit status of the sensingdevice and produce an electrical signal proportional to the levelof the measured fluid in the tank.4.2.1.4 Time Domain ReflectometryThe time domain re-flectometry sensing technique uses a high frequency electr
22、o-magnetic wave transmitted along a transmission line, wire,cable, or rod to determine the level of the measured liquid(s) bydetecting changes in and timing the reflected energy.4.2.1.5 CapacitiveThe capacitive-sensing technique usesthe change in capacitance of the sensing device to produce anelectr
23、ical signal proportional to the level of the measured fluidin the tank.4.2.1.6 Resistance TapeThe resistance-tape-type sensingtechnique uses the change in circuit resistance in the sensingdevice to produce an electrical signal proportional to the levelof the measured fluid in the tank.4.2.1.7 Static
24、 PressureThe static head technique mea-sures the static (head) pressure caused by the measured liquidrelative to the ambient pressure to change the circuit status ofthe sensing device and produce an electrical signal proportionalto the level of the measured fluid in the tank.4.2.1.8 RadarThe radar t
25、echnique uses a high frequencyelectromagnetic wave transmitted through the air, includingguided inside a hollow tube, to determine the level of themeasured liquid(s) by detecting changes in and/or timing thereflected energy.4.2.1.9 UltrasonicThe ultrasonic technique uses high fre-quency sonic waves
26、transmitted either through the air or in theliquid to be measured, to determine the measured liquid(s)level by detecting changes in and/or timing the reflectedenergy.4.3 Process MediumThe following are the most commontypes of process media. The first column identifies fluids thatare measured in the
27、tank. The second column identifies theliquid or gas that interfaces with the measured fluid.Fluid Liquid or GasContaminated fuel airContaminated oil compressed airFuel (diesel fuel, cargo fuel, gasoline) compressed gasFreshwater, potable water, feed water WaterHydraulic oil steamJP-5, JP fuels seawa
28、terLubricating oil wastewaterRefrigerantsSynthetic oilSeawaterTurbine oilWaste oilWastewater, sanitary waste4.4 Pressure RangeThe liquid level indicating equipmentmust be able to withstand the expected fluid pressures in thetank. Pressure range specification must take into accountexpected pressures
29、to be encountered in differing tank sizes andfluid types for a particular sensor type.4.5 DisplayThe display for liquid level indication istypically specified as analog, digital, or both.5. Ordering Information5.1 The purchaser shall provide the manufacturer with all ofthe pertinent application data
30、 shown in accordance with 5.2. Ifspecial application operating conditions exist that are notshown in the acquisition requirements, they shall also bedescribed.5.2 Acquisition RequirementsAcquisition documentsmust specify the following:(a) Title, number, and date of this specification;(b) Manufacture
31、rs part number;(c) Sensing technique;(d) Application;(e) Pressure range;(f) Display requirements (see 4.5) and indication range;(g) Indicator panel assembly mounting method;(h) Indicator panel assembly requirements;(i) System operating characteristics;(j) Materials;(k) Environmental requirements;(l)
32、 Quantity of liquid level indicating equipment required;(m) Size and weight restrictions (see 7.5);(n) Critical service life requirements (see 8.1);(o) Performance requirements (see 8.2);(p) Special surface finish requirements (see 9.1);(q) When certification is required (see Section 13);(r) Special
33、 marking requirements (see Section 14);(s) Special packaging or package marking requirements(see Section 15);(t) When ISO 9001 quality assurance system is not re-quired (see 16.1); and(u) Special warranty requirements (see 16.2).6. Materials and Manufacture6.1 Sensing DevicesThe materials for the se
34、nsing devicesand wetted pans shall be selected for long-term compatibility(see 8.1) with the process medium (see 4.3).F20440026.2 Material InspectionThe manufacturer shall be respon-sible for ensuring that materials used are manufactured, exam-ined, and tested in accordance with the specifications a
35、ndstandards as applicable.7. Physical Properties7.1 EnclosureUnique or special enclosure requirementsshall be specified in the acquisition requirements (see 5.2).7.2 Liquid Level Indicating Equipment MountingLiquidlevel indicating equipment is commonly mounted using brack-ets or similar hardware.7.3
36、 External ConfigurationThe outline drawing shallshow the configuration with dimensions in SI units (inch-pound units). The outline drawing shall include limitingdimensions for electrical connections if required. The outlinedrawing shall indicate the mounting method with hole size,center location, an
37、d other pertinent dimensions. Wherethreaded holes are used, thread specifications shall be provided.7.4 Electrical ConnectionElectrical flexible interconnec-tions shall be provided with each liquid level indicating sensoras specified in the contract (see 5.1).7.5 Size and WeightThe user may have int
38、ended applica-tions in which size and weight are limited. Size and weightrestrictions shall be specified in the acquisition requirements(see 5.2).8. Performance Requirements8.1 Service LifeThe user may have a minimum specifiedservice life requirement that may be critical. Critical servicelife requir
39、ements shall be specified in the acquisition require-ments (see 5.2).8.2 Liquid Level Indicating Equipment PerformancePerformance tolerances are usually specified in percent ofindicator full scale. Critical performance requirements shall bespecified in the acquisition requirements (see 5.2). The fol
40、low-ing performance characteristics and environmental exposuresmay or may not be important to each users intended applica-tion.AccuracyResponse timeRepeatabilityHysteresisInsulation resistanceSpecific gravityFluid conductivityTank wall proximityInclinationSpike voltageSalt sprayPressureVibrationShoc
41、kEnclosuredc magnetic fieldElectromagnetic interference (EMI)ImmersionSupply line voltage and frequency variation9. Workmanship, Finish, and Appearance9.1 Finish and AppearanceAny special surface finish andappearance requirements shall be specified in the acquisitionrequirements (see 5.2).10. Inspec
42、tion10.1 Classification of InspectionsThe inspection require-ments specified herein are classified as follows:(a) First article tests (see 10.2) and(b) Conformance tests (see 10.3).10.2 First Article TestsFirst article test requirements shallbe specified, where applicable. First article test methods
43、 shouldbe identified for each design and performance characteristicspecified. Test report documentation requirements should alsobe specified.10.3 Conformance TestsConformance testing is accom-plished when first article tests were satisfied by a previousacquisition or the product has demonstrated rel
44、iability insimilar applications. Conformance tests are usually less inten-sive than first article tests, often verifying that samples of aproduction lot meet a few critical performance requirements.11. Number of Tests and Retests11.1 Test SpecimenThe number of test specimens to besubjected to first
45、article tests shall be specified and shoulddepend on the liquid level indicating equipment design. Gen-erally, one liquid level indicating equipment of each type (thatis, sensing technique, application, pressure range, display, andindication range) shall be subjected to first article testing.12. Tes
46、t Data12.1 Test DataTest data shall remain on file at themanufacturers facility for review by the buyer upon request. Itis recommended that test data be retained in the manufacturersfiles for at least three years or a period of time acceptable to thebuyer and manufacturer.13. Certification13.1 When
47、specified in the acquisition requirements (see5.2), the buyer shall be furnished certification that samplesrepresenting each lot have been either tested or inspected asdirected in this specification and the requirements have beenmet.14. Product Marking14.1 User specified product marking shall be lis
48、ted in theacquisition requirements (see 5.2). The minimum data to beclearly marked on each liquid level indicating equipment shallinclude the following:(a) Manufacturers name,(b) Manufacturers part number,(c) Serial number or lot number,(d) Date of manufacture (not required if serial number istracea
49、ble to date of manufacture), and(e) Excitation voltage.15. Packaging and Package Marking15.1 Packaging of Product for Delivery Product shouldbe packaged for shipment in accordance with Practice D 3951.F204400315.2 Any special packaging or package marking require-ments for shipment or storage shall be identified in theacquisition requirements (see 5.2).16. Quality Assurance16.1 Quality SystemA quality assurance system in accor-dance with ISO 9001 shall be maintained to control the qualityof the product being supplied effectively, unless oth
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