1、Designation: F 2044 09An 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 () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This specification covers
3、 the requirements for electricalliquid level indicating equipment for shipboard 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 inclu
4、des compensating tanks in which theequipment must locate the interface.1.2 Each 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
5、assembly, when required; and(e) Portable indicator panel assembly, when required.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 no
6、t purport to address all of thesafety concerns, if any, associated with its use. 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 shipb
7、oard applicationsare included in the Supplement to this standard.2. Referenced Documents2.1 ASTM Standards:2D 3951 Practice for Commercial Packaging2.2 ISO Standards:9001 Quality System Model for Quality Assurance inDesign/Development, Production, Installation, and Ser-vicing33. Terminology3.1 Defin
8、itions:3.1.1 hysteresismaximum difference in output, at anymeasurand value within 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 equip
9、mentand between insulated portions of a liquid level indicatingequipment and ground 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 measu
10、rand.3.1.4 pressure cyclingthe specified minimum number ofspecified periodic pressure 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 repeatabili
11、tyability of a liquid level indicatingequipment to reproduce output readings when 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.
12、1.8 signal conditioneran electronic device that makesthe output signal from a sensor 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.1This specification is under the jurisdictio
13、n of ASTM Committee F25 on Shipsand Marine Technology and is the direct responsibility of Subcommittee F25.10 onElectrical.Current edition approved Aug. 1, 2009. Published August 2009. Originallyapproved in 2000. Last previous edition approved in 2000 as F 2044 - 00, which waswithdrawn in March 2009
14、 and reinstated in August 2009.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American Natio
15、nal Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4. Designation4.1 DesignationMost liquid level indicating equipmentmanufacturers use des
16、ignations or systematic numbering oridentifying 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
17、an indicator panel assembly to show 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 sensingdevice
18、s is used in liquid level indicating equipment. In themost common types of devices, sensing techniques such asadmittance/impedance, magnetic float, static pressure, differ-ential pressure, time domain reflectometry, radar, capacitive,resistance tape-type and ultrasonic are used. The function ofthe s
19、ensing device is to produce a measurable response to theadmittance, impedance, differential pressure, reflected 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 sensi
20、ng device typicallydoes not use any part of the tank structure as part of the sensingdevice.4.2.1.1 Admittance 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 resp
21、ect to the level of the measuredfluid in the tank.4.2.1.2 Magnetic FloatThe magnetic float sensing tech-nique 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 measu
22、red fluid in the tank.4.2.1.3 Differential PressureThe differential pressure-sensing technique uses the pressure 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.
23、4.2.1.4 Time Domain ReflectometryThe time domain re-flectometry sensing technique uses a high frequency electro-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 Capa
24、citiveThe capacitive-sensing technique usesthe change in capacitance of the sensing device to produce anelectrical 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 sensingde
25、vice to produce an electrical signal proportional to the levelof the measured fluid in the tank.4.2.1.7 Static 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 pr
26、oduce an electrical signal proportionalto the level of the measured fluid in the tank.4.2.1.8 RadarThe radar technique 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
27、and/or timing thereflected energy.4.2.1.9 UltrasonicThe ultrasonic technique uses high fre-quency sonic waves 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 fo
28、llowing are the most commontypes of process media. The first column identifies fluids thatare measured in the 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 fu
29、el, gasoline) compressed gasFreshwater, potable water, feed water WaterHydraulic oil steamJP-5, JP fuels seawaterLubricating oil wastewaterRefrigerantsSynthetic oilSeawaterTurbine oilWaste oilWastewater, sanitary waste4.4 Pressure RangeThe liquid level indicating equipmentmust be able to withstand t
30、he expected fluid pressures in thetank. Pressure range specification must take into accountexpected pressures 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.
31、Ordering Information5.1 The purchaser shall provide the manufacturer with all ofthe pertinent application data 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 RequirementsAcqu
32、isition documentsmust specify the following:(a) Title, number, and date of this specification;(b) Manufacturers 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 pane
33、l assembly requirements;(i) System operating characteristics;(j) Materials;(k) Environmental requirements;(l) 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);F204
34、4092(p) Special surface finish requirements (see 9.1);(q) When certification is required (see Section 13);(r) Special 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); an
35、d(u) Special warranty requirements (see 16.2).6. Materials and Manufacture6.1 Sensing DevicesThe materials for the sensing devicesand wetted pans shall be selected for long-term compatibility(see 8.1) with the process medium (see 4.3).6.2 Material InspectionThe manufacturer shall be respon-sible for
36、 ensuring that materials used are manufactured, exam-ined, and tested in accordance with the specifications andstandards 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 E
37、quipment MountingLiquidlevel indicating equipment is commonly mounted using brack-ets or similar hardware.7.3 External ConfigurationThe outline drawing shallshow the configuration with dimensions in SI units (inch-pound units). The outline drawing shall include limitingdimensions for electrical conn
38、ections if required. The outlinedrawing shall indicate the mounting method with hole size,center location, and other pertinent dimensions. Wherethreaded holes are used, thread specifications shall be provided.7.4 Electrical ConnectionElectrical flexible interconnec-tions shall be provided with each
39、liquid level indicating sensoras specified in the contract (see 5.1).7.5 Size and WeightThe user may have intended 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 LifeTh
40、e user may have a minimum specifiedservice life requirement that may be critical. Critical servicelife requirements 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
41、scale. Critical performance requirements shall bespecified in the acquisition requirements (see 5.2). The follow-ing performance characteristics and environmental exposuresmay or may not be important to each users intended applica-tion.AccuracyResponse timeRepeatabilityHysteresisInsulation resistanc
42、eSpecific gravityFluid conductivityTank wall proximityInclinationSpike voltageSalt sprayPressureVibrationShockEnclosuredc magnetic fieldElectromagnetic interference (EMI)ImmersionSupply line voltage and frequency variation9. Workmanship, Finish, and Appearance9.1 Finish and AppearanceAny special sur
43、face finish andappearance requirements shall be specified in the acquisitionrequirements (see 5.2).10. Inspection10.1 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
44、 Article TestsFirst article test requirements shallbe specified, where applicable. First article test methods shouldbe identified for each design and performance characteristicspecified. Test report documentation requirements should alsobe specified.10.3 Conformance TestsConformance testing is accom
45、-plished when first article tests were satisfied by a previousacquisition or the product has demonstrated reliability 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 requir
46、ements.11. Number of Tests and Retests11.1 Test SpecimenThe number of test specimens to besubjected to first 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, a
47、pplication, pressure range, display, andindication range) shall be subjected to first article testing.12. Test 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
48、 at least three years or a period of time acceptable to thebuyer and manufacturer.13. Certification13.1 When 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 specif
49、ication and the requirements have beenmet.14. Product Marking14.1 User specified product marking shall be listed in theacquisition requirements (see 5.2). The minimum data to beF2044093clearly 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 istraceable to date of manufacture), and(e) Excitation voltage.15. Packaging and Package Marking15.1 Packaging of Product for Delivery
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