1、AMSC N/A FSC 5950 MIL-T-27/138B 8 June 2012 SUPERSEDING MIL-T-27/138A 13 March 1991 MILITARY SPECIFICATION SHEET TRANSFORMER, POWER, STEP-DOWN, 3-PHASE This specification is approved for use by all Depart- ments and Agencies of the Department of Defense. The complete requirements for procuring the p
2、roduct described herein shall consist of this document and the latest issue of specification MIL-PRF-27. NOTES: 1. Dimensions are in inches. 2. Metric equivalents are given for general information only. 3. Tolerance on terminal position dimensions is .015 (0.38 mm). 4. Marking shall be on the top of
3、 the case. FIGURE 1. Dimensions and configuration. Inches mm .190 4.83 .47 11.9 .53 13.5 .610 15.49 .62 15.7 .640 16.3 .75 19.0 .93 24.9 1.02 25.9 4.490 114.05 4.510 114.44 5.65 143.5 5.75 146.0 6.490 164.8 6.510 165.34 8.500 215.90 INCH-POUNDInactive for new design after 13 March 1991. Provided by
4、IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-T-27/138B 2 REQUIREMENTS: (When numbers in parentheses, i.e., (1-2) are used, they indicate the winding and the extreme terminals of the windings.) Electrical ratings: Primary power: 585 watts each phase. Prima
5、ry voltage: (1-2) (5-6) (9-10): 226 volts rms 5 percent, 400 Hz, 3-phase. Secondary voltage: (3-4) (7-8) (11-12): 14 volts rms, 40 amperes rms .5 volt. DC resistance: (1-2) (5-6) (9-10): 0.5 ohm maximum. (3-4) (7-8) (11-12): 0.1 ohm maximum. Working voltage: (1-2) (5-6) (9-10): 335 volts maximum. (3
6、-4) (7-8) (11-12): 175 volts maximum. Design and construction: Dimensions and configuration: See figure 1. Duty cycle: Continuous. Case: Metal. Terminals: Ceramic standoff type. Terminal height: 1.06 inch maximum. Weight: 30 pounds maximum. Operating temperature range: -55C to +130C. Terminal streng
7、th: MIL-STD-202, method 211, test condition A, 5.0 pounds. Dielectric withstanding voltage: At sea level: (1-2) (5-6) (9-10): 1,000 volts dc. (3-4) (7-8) (11-12): 500 volts dc. At barometric pressure: (1-2) (5-6) (9-10): 900 volts dc. (3-4) (7-8) (11-12): 455 volts dc. Electrical characteristics: No
8、 load: With 226 volts rms, 400 Hz, 3-phase across (1-2) (5-6) (9-10). Voltage across (3-4) (7-8) (11-12): 17 volts maximum. Rated load: with 226 volts rms, 400 Hz, 3 phase across (1-2) (5-6) (9-10), the voltage across (3-4) (7-8) (11-12) shall be 14 volts 0.5. Provided by IHSNot for ResaleNo reprodu
9、ction or networking permitted without license from IHS-,-,-MIL-T-27/138B 3 Polarity: Additive with terminals 2 and 3; 6 and 7; 10 and 11 connected. Temperature rise: 45C maximum with 226 volts rms 5 percent, 400 Hz, 3 phase across (1-2) (5-6) (9-10) at an ambient temperature of 85C. Salt spray: The
10、transformers shall be subjected to a 20 percent salt spray solution for 50 hours. VERIFICATION: Qualification inspection: Not applicable. Conformance inspection: Groups A and B tests of MIL-PRF-27 shall be applicable. Marking location: See figure 1. Part or Identifying Number (PIN): M27/138-01. Chan
11、ges from previous issue. The margins of this specification are marked with vertical lines to indicate where changes from the previous issue were made. This was done as a convenience only and the Government assumes no liability whatsoever for any inaccuracies in these notations. Bidders and contracto
12、rs are cautioned to evaluate the requirements of this document based on the entire content irrespective of the marginal notations and relationship to the last previous issue. Referenced documents. In addition to MIL-PRF-27, this document references the following: MIL-STD-202 Custodians: Preparing ac
13、tivity: Army - ER DLA - CC Navy - EC Air Force 85 (Project 5950-2009-087) DLA - CC Review activities: Army AR, CR4, MI Navy AS, MC, OS, SH Air Force - 19, 99 NOTE: The activities listed above were interested in this document as of the date of this document. Since organizations and responsibilities can change, you should verify the currency of this information above using the ASSIST Online database at https:/assist.daps.dla.mil . Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
