1、 MIL-PRF-YIIC 9999906 20Yb07L 630 = MIL-PRF-43891C SUPERSEDING MIL-R-0043891B (GL) 20 March 1992 MIL-R-43891A 29 December 1977 PERFORMANCE SPECIFICATION REFRIGERATION UNITS, ELECTRIC, 9000 BTU FOR MILITARY VAN CONTAINER, REFRIGERATED, INSULATED This specification is approved for use by all Departmen
2、ts and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope. This document covers one type and size of insulated, electric refrigeration unit having a capacity of 9000 British thermal units (Btu) per hour and used with military van containers (see 6.1). 2. APPLICABLE DOCUMENTS 2.1 General. The
3、documents listed in this section are specified in sections 3 and 4 of this specification. This section does not include documents cited in other sections of this specification or recommended for additional information or as examples. effort has been made to ensure the completeness of this list, docu
4、ment users are cautioned that they must meet all specified requirements documents cited in sections 3 and 4 of this specification, whether or not they are listed. While every Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use in improving this docu
5、ment should be addressed to: Development, and Engineering Center, Natick, MA 01760-5018 by using the self-addressed Standardization Document Improvement Proposal (DD Form 1426) appearing at the end of this document or by letter. AMSC N/A FSC 4110 U.S. Army Natick Research, I Licensed by Information
6、Handling ServicesMIL-PRF-Y3%LC = 9999906 204b072 577 = MIL-PRF-43891C 2.2 Government docu ments. 2.2.1 Standards. The following standards form part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those listed in the issue of the Departme
7、nt of Defense Index of Specifications and Standards (DoDISS) and supplement thereto, cited in the solicitation (see 6.2) . STAN DARDS DEPARTMENT OF DEFENSE MIL-STD-461 - Requirements for the Control of Electromagnetic Interference Emissions and Susceptibility Characteristics Guidelines (Metric) MIL-
8、STD-462 - Measurement of Electromagnetic Interference MIL-STD-810 - Environmental Test Methods and Engineering MIL-STD-1474 - Noise Limits for Military Materiel (Unless otherwise indicated, copies of the above standards are available from the Standardization Document Order Desk, 700 Robbins Avenue,
9、Building 4D, Philadelphia, PA 19111-5094). 2.3 Non-Government Dublicationz . The following documents form a part of this document to the extent specified herein. Unless otherwise specified, the issues of the documents which are DoD adopted are those listed in the issue of the DoDISS cited in the sol
10、icitation. Unless otherwise specified, the issues of documents not listed in the DoDISS are the issues of the documents cited in the solicitation (see 6.2). NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION (NEMA) Standards Publication No. 250 - Enclosures for Electrical Equipment (Application for copie
11、s should be addressed to the National Electrical Manufacturers Association, 1300 No. 17th Street, Suite 1847, Rosslyn, VA 22209). 2 Licensed by Information Handling Services. MIL-PRF-43891C 999990b 2046073 403 MIL-PRF-43891C NATIONAL FIRE PROTECTION ASSOCIATION (NFPA) Standard No. 70 - National Elec
12、trical Code (Application for copies should be Protection Association, One Battery 9101). INTERNATIONAL ORGANIZATION addressed to the National Fire March Park, Quincy, MA 02269- FOR STANDARDIZATION Standard 1496-2 - Thermal Containers (Application for copies should be addressed to the American Nation
13、al Standards Institute, 11 West 42nd Street, New York, NY 10036). UNDERWRITERS LABORATORIES INC. (UL) Standard 207 - Refrigerant Containing Components and Accessories, Standard 303 - Refrigerant and Air Conditioning Condensing and Standard 353 - Limit Controls Nonelectrical Compressor Units (Applica
14、tion for copies should be addressed to the Underwriters Laboratories, Inc., 333 Pfingsten Road, Northbrook, IL 60062-2096). 2.4 Order of precedence. In the event of a conflict between the text of this document and the references cited herein, the text of this document takes precedence. Nothing in th
15、is document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. 3. REQUIREMENTS 3.1 First article. When specified (see 6.2), a sample shall be subjected to first article inspection in accordance with 4.1.1. 3.2 0?3 eratina reuuirements. Refrigeration u
16、nits shall satisfy the following minimum functional, operational and performance requirements. 3.2.1 4-hour oDeration. Refrigeration units shall operate properly with suction and discharge pressures safely controlled. 3 Licensed by Information Handling ServicesMIL-PRF-43891C 99Ob 2046074 34T MIL-PRF
17、-43891C 3.2.2 72-hour oDeratio n. Refrigeration units shall operate properly and maintain proper conditions at thermostat settings of OF and 35F. 3.2.3 Befr iaeration caDacitv. Refrigeration units shall have minimum net capacities of 9,000 Btu/hr at a thermostat setting of OF and 11,000 Btu/hr at a
18、thermostat setting of 35F. 3.2.4 Heatina car, acity. Refrigeration units shall have a gross heating capacity of not less than 7,000 Btu/hr at a thermostat setting not less than 45F. 3.2.5 Defrost svs tem. Refrigeration units shall have a defrost cycle terminated by temperature, control adjustable be
19、tween 6 and 24 hours and have the capacity to produce not less than 10 pounds of condensate within 30 minutes. The defrost system shall have provisions for manual defrost override. automatically initiated by a time 3.2.6 Dra inaae svste m. Refrigeration units shall have a drainage system for the col
20、lection and discharge of condensate to the outside of the unit. 3.2.7 Moisture content . The moisture content of the refrigeration system shall be kept at a minimum to maintain proper operation of the refrigeration unit. 3.2.8 Ref riaera nt le akaae. Refrigerant containing components shall be gastig
21、ht. 3.2.9 Co ntrol Pa ne. The refrigeration units shall have a control panel for the operator having, but not limited to, the following 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. items: Start, run, stop control Operation indicator Refrigerator internal temperature control Refrigeration unit running time ind
22、icator High and low side pressure indicators Refrigerator interior temperature indicator Manual defrost control Defrost operation indicator Heating cycle operation indicator Refrigeration cycle operation indicator Power supply circuit breaker 4 Licensed by Information Handling ServicesMIL-PRF- 4 38
23、91C 3.2.10 The refrigerant shall be commercially available nonozone-depleting, and environmentally safe. Class I ozone-depleting substances, as determined by the Environmental Protection Agency (EPA), shall not be contained in, and shall be prohibited from use during the fabrication of the refrigera
24、tion unit (see 6.6) . 3.2.11 TemDe rature CO ntrol . The selected temperature of the refrigeration units shall be controlled automatically. The temperature control shall allow an incremental selection of normal refrigerator/freezer temperatures. When temperature settings are below 20F, the heating c
25、ycle shall not operate. 3.2.12 Po wer requireme nts. Unless otherwise specified (see 6.2), the refrigeration unit shall operate on 208/230 volt, 3- phase, 60-hertz (Hz) and 200 volt, 3-phasef 50-Hz power. 3.2.12.1 Power suqlv cable . The refrigeration unit shall be supplied with a power supply cable
26、 capable of operating properly with the power source and permanently attached to the outside of the unit. 3.2.12.2 Liahtina power SUD? IV cable. The refrigeration unit shall be supplied with a minimum 46-foot, SO type cable for 110 volt container lighting permanently attached to the outside of the r
27、efrigeration unit. 3.2.13 Finish The refrigeration units, except where detrimental to proper operation, shall have a nontoxic chemical agent resistant green finish (see 6.7.1). The word “CARC“, together with the month and year of finishing, shall be stencilled near the identification plate in block
28、letters not less than 1 inch high using lusterless black chemical agent resistant paint (see 6.7.2). All paint shall be properly applied. 3.2.14 Safety. The refrigeration units shall minimize flammability, operational, and personnel hazards. 3.2.15 Airflow. The air exiting the evaporator shall be di
29、rected to create proper circulation inside the refrigerator it is used with. 3.3 Sumort or ownership recruirements. Refrigeration units shall meet the following requirements. 5 Licensed by Information Handling ServicesMIL-PRF-43891C 3.3.1 Tr ansportability. Refrigeration units shall be able to be ha
30、ndled by a forklift truck and by lifting eyes or similar devices located on the top of the unit. 3.3.2 Desian reliabil itv . Refrigeration units shall be reliable and designed to operate without failure when subjected to the design reliability test. 3.3.3 j ain en nce. All major components shall be
31、accessible for adjustment, maintenance, servicing, and replacement without removing any other major component. All other components and assemblies shall be designed for ease of installation and replacement and shall be accessible for maintenance, repair, service and replacement with minimum disturba
32、nce to adjacent components. No special tools shall be needed for any maintenance, repair, service, installation or replacement action. Condenser and evaporator fins shall be protected from any damage that might occur during servicing or maintenance actions. Operator personnel shall be able to visual
33、ly check the moisture content of the refrigeration system on all refrigeration units. All points requiring lubrication shall be equipped with standard fittings and shall be accessible from the outside of the unit. Each unit shall have the fittings or location tagged to indicate the temperature and g
34、rade of lubricant used and recommended frequency of lubrication. 3.3.4 Marki nq . Identification, instruction, control and gage plates shall be of corrosion-resistant material permanently . attached to the outside of the refrigeration unit. Numbering and lettering shall be legible and permanently in
35、scribed and shall be no less than 1/16 inch in height. All plates shall blend with the framed enclosure finish and shall have a nonreflective surface. 3.3 4.1 t * The identification plate shall contain theJ-?; Safety requirements shall be verified a follows. 16 Licensed by Information Handling Servi
36、ces MIL-PRF-438SLC m 0b 20qhOB7 TTB m MIL-PRF-43891C 4.3.2.12.1 Wirinu certification. Wiring practices used in the refrigeration units shall be certified as conforming to NFPA Standard No. 70 by submission of the manufacturers certification, a certified test report or appropriate labels or listing m
37、arks. 4.3.2.12.2. Electr ical enclosur e certificati on. Electrical enclosures (junction boxes, control boxes, etc.) shall be certified as conforming to the watertightness requirements of NEMA Standards Publication No. 250 by submission of the manufacturers certification, a certified test report or
38、appropriate labels or listing marks. 4.3.2.12.3 Refrigerant containinu CO mPonents Cer tification. Refrigerant containing components used in the refrigeration units shall be certified as conforming to UL Standard 207; condensing units and compressors used shall be certified as conforming to the requ
39、irements of UL Standard 303 and limit controls used shall be certified as conforming to UL standard 353. Verification of certification shall be done by submission of the manufacturers certification, a certified test report or appropriate labels or listing marks. 4.3.2.12.4 Personnel safetv inspectio
40、n. Visually verify that a plate indicating “Danger, Rotating Fan“ has been permanently attached on both sides of the condenser. 4.3.3 Sunnort or ownership reuuirements verification. All ownership and support requirements shall be verified as follows. 4.3.3.1 TransPortability test. The refrigeration
41、unit, loaded to 1-1/2 times the weight of the unit, shall be lifted, transported, and placed in position by a forklift truck without securing the unit in any way to the truck. During the transport, the truck shall be driven over a 4-inch by 4-inch board so either the two left or two right tires go o
42、ver the board. After the forklift transport, the refrigeration unit shall be raised by its lifting eyes or similar devices and held suspended for 5 minutes. Upon completion, visually examine the unit to verify that there is no damage or distortion. 4.3.3.2 Desian reliability test. A 2500-hour design
43、 reliability test shall be run as follows: a. A maximum of two units shall be used for this test. When two units are used, each unit shall be tested for a minimum of 1000 operating hours and their combined testing time must equal 2500 17 Licensed by Information Handling ServicesMIL-PRF-43891C operat
44、ing hours. Operating hours for the units shall be the hours the compressor is operating. b. The refrigeration unit shall be clamped to the evaporator opening of the calorimeter (see 4.3.2.3.1) with a minimum volume of 150 cubic feet. compressor will cycle with running time of approximately 75 percen
45、t when the condenser air entering temperature is llOF. condensing section shall be maintained at a minimum of llOF for 90 percent of the operating hours and at a minimum of 125F for 10 percent of the operating hours. hour period of operating time. set at 0F for 36 hours and at 40F for the next 36 ho
46、urs. This cycle hall be repeated until all operating hours have been completed. During the test, suction and discharge pressures, air temperature entering the condenser, refrigerated enclosure temperature, and compressor operating hours shall be recorded every hour on automated recording instruments
47、. closure, failure to start and operate, failure to defrost, or any mechanical or control failure that requires more than 30 minutes to repair, shall be defined as a unit failure. A malfunction that can be repaired in less than 30 minutes shall be classified as an incident. shall be analyzed, correc
48、tion made, and the test started from time zero. All failures, analyses, and corrective actions shall be recorded. completed all operating hours without failure and with no more 5 incidents. c. A heat load shall be imposed on the unit so the d. The air entering the condenser and surrounding the e. Th
49、e defrost control shall be set for two defrosts in a 24- f. The refrigeration shall be operated with the thermostat g. Failure of the unit to maintain the,temperature of the h. When failure to complete test hours occurs, the failure i. The test shall be successfully completed when the unit has 4.3.3.3 Ser vice and minten ance simulation. A simulated demonstration shall be accomplished verifying that all major refrigeration unit components are accessible for adjustment, maintenance, servicing and replacement without the removal of any other major component or n
