1、MIL-E-28968 (Mc) 20 May 1971 MILITARY SPECIFIC AT ION ELECTRONIC SHOP, TRANSPORTABLE : EXPANDABLE, EQUIPMENT REPAIR FACILITY 1. SCOPE 1.1 This specification covers one transportable equipment repair,facil type of by elec expandable - ronic shop with repair and environmental equipment compactly insta
2、lled. 2. APPLICABLE DOCUMENTS 2.1 The following documents of the issue in effect on date of invitation for bids or request for proposal, form a part of the specification to the extent specified herein. SPEC IF ICAT IONS FEDERAL L-P-387 - Plastic Sheet, Laminated, Thermosetting TT-E-529 - Enamel, Alk
3、yd, Semigloss. ZZ-R-765 - Rubber, Silicone: Low-and-High-Tem- ZZ-T-416 - Tire Rebuilding and Tire and Tube DDD-T-86 - Tape, Textile, Cotton, General Purpose, PPP-F-3 20 - Fiberboard, Corrugated And Solid, (for Designation Plates) . perature and Tear Resistant. Repair Materials. (Unbleached, Bleached
4、 or Dyed) . Sheet Stock (Container Grade) And Cut Shapes. PPP-P-291 - Paperboard, Wrapping, Cushioning. MILITARY MIL-P- 1 16 - Preservation, Methods Of . MIL-T- 1 5 2 - Treatment, Moisture-and Fungus-Resistant, Of Communications, Electronic, And Associated Electrical Equipment. Cables and ground 3.3
5、.1.9.1 Power cables. The contractor shall furnish rods shall be supplied for each shelter as follows. four external power cable assemblies. shall be used to connect the 60-Hz source to the shelters. The other two cable assemblies shall connect the 400-Hz source to the shelters, The 60-Hz cable assem
6、blies shall be 75 feet long and consist of four No. 6 AWG stranded insulated conductors in a flexible neoprene jacket. The 400-Hz cable assemblies shall be 75 feet long and consist of four No. 10 AWG stranded insulated conductors in a flexible neoprene jacket. Each cable shall be terminated with con
7、nectors to mate with the shelterspower input receptacles on one end and with connectors to mate with the shelterslpower output receptacles on the other. addition, four 4-foot-long adaptei: cables shall be provided or connection of the power cables to the output studs of diesel engine generators PU-2
8、39/G, PU-344/G, PU-454/G or PU-608/G, The cable connectors (including the adapter cable connector) shall include a watertight cap and chain assembly. The intent of these cables and adapters is to provide input power to the shelters in the SSC or ESC from generator sets or for interconnection of the
9、power inputs of both shelters when operating in the ESC mode powered from a single power source. 3.3.10.9.2 Ground cable. The contractor shall furnish four ground cables 8 feet long. 3.3.10.9.3 Ground rods. The contractor shall furnish four ground rods 6 feet long complete with ground cable clamp an
10、d liTii handle. Two cable assemblies In 12 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-E-28968 i.19 9999906 0247895 4 m. MIL-E-28968 (MC) 3.3.10.10 Color codinq. Color coding for the 60-Hz and 400-Hz power distribution systems including the p
11、ower input cables shall be as follows: Black Phase A (Tl) Red Phase B (T2) Green Phase C (T3) White Neutral or Ground (TO) 3.3.11 Lishtinq. The shelters shabl be equipped with fluorescent lights, incandescent lights, and blackout protection. A minimum of 80- to 100-foot candles at work bench level s
12、hall be provided. All lighting circuits shall be 115 Y nominal, 60 Hz. The lighting circuits shall be protected by circuit breaker(s) located on the power control panel. 3.3.11.1 Fluorescent liqhtinq. General lighting of each shelter shall be by means of two rows of double tube shallow fluorescent f
13、ixtures with line f-ilters, .diffusing shields, radiation shields, and removable plastic covers. Each row of lights shall be controlled by a switch. The switches shall be located on the blackout interlock box. In the ESC, -two rows of quick-connect/disconnect, double fluorescent lighting fixtures sh
14、all be provided with line filters, diffusing- shields, Padiation shields, removable plastic covers and the capability of being connected into either shelters lighting system by a threaded keyed-type connector. 3.3.11.2 Incandescent liqhtinq. Incandescent lighting shall be furnished to illuminate the
15、 work benches. The lights shall be located under the equipment racks and be controlled by separate switches located near the lights. The light bulbs shall be of the rough service type and shall be vertically mounted in shock-absorbing bases. In the ESC, quick-connect/disconnect wall-mounted fixtures
16、 either shelter bench lighting system by threaded, keyed-type connector. Separate switches shall be located on wall-mounted fixtures . .shall be provided with capability to interconnect into Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-E-289b
17、49 W 9999906 OZL(783b b W MILIE-28968 (MC) 3.3.11.3 Blackout protection. To insure positive blackout protection, all shelter openings through the wall shall be made lighttight. Electrical interlocks shall be arranged so that if the outside doors are opmed, the lighting circuits shall be broken. The
18、shelters shall include a blackout curtain inside the doors. A neon lamp shall be mounted over the doors to give a small amount of illumination and the circuit shall permit the neon lamp to be left on continuously, Under blackout conditions, the doors interlock switches shall be operated to the IIOFF
19、fl psition. When the lighting circuits are broken, the operation of any equipwent in use shall not be disrupted. The blackout interlock and light switch box shall be mounted on the interior wall to the left of the doors as you enter. 3.3.92 Air conditioninq. Two air conditioners for each shelter sha
20、ll be contractor furnished and shall be Airflow model PAC-2-Sl0, or equal, for a total cooling capacity of 30,000 British thermal unithour (Btu/h). Installation shall be in accordance with Data List PZlOl, except as otherwise specified herein. All associated items necessary for the proper operation
21、and installation of the two air conditioners shall be supplied. Both air conditioners shall be identical and completely inter- changeable. 3.3.12.1 Air conditioner. The two air conditioners shall be in accordance with Data List PZ101 and each shall meet the following requirements. Each air condition
22、er shall be a complete self-contained unit with convenient mounting brackets for mounting on the exterior of the fixed forward wall o each shelter. The design of the unit shall be rugged enough to withstand vibrations encountered on the Munson Road Course and the Perryman Cross-Country.Course No. 1
23、at Aberdeen Proving Grounds, Maryland, without fall-out or drop, or ahock/vibration movement which would damage the air conditioner. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- MIL-E-28968 (MC) 3.3.12.1.1 Coolinq capacity. Each air conditioner s
24、hall have a cooling capacity of 15,000 gtu/h at sea level with an ambient temperature of 131 F. The unit shall be designed for 85 to 90 percent sensible cooling effect . 3.3.12.1.2 Refriqerant. Each air conditioning unit shall employ either R-12 or R-22 Freon refrigerant and shall be delivered with
25、full charge. 3.3.12.1.3 Moisture content. The moisture content by weight, in the liquid-phase, after being dehydrated and charged with refrigerant, shall not exceed 25parts per million. 3.3.12.1.4 Compressor. The compressor shall be a hermetically sealed type and shall have performance characteristi
26、cs to meet capacity requirements. and discharge service valves shall be provided. Suction 3.3.12.1.5 *Expansion valve. The expansion valve shall be a thermostatic type suitable to give proper pressure, superheat and capacity, and shall have a pressure limiting feature to prevent compressor overload
27、when the air conditioning unit is started with 131F air entering the evaporator and condenser. 3.3.12.1.6 Drier. The drier shall be of the drier- strainer type, shall employ silica gel as the desiccant and shall be the throw away type. 3.3.12.1.7 Siqht qlass. A combination liquid sight glass and moi
28、sture indicator shall be employed. The moisture indicator shall indicate by change in color when a new drier element is required. 3.3.12.1.8 Air handlinq components. All air fans shall be directly connected to their respective motor shafts. Fans shall be statically and dynamically balanced. 3.3.12.1
29、.9 Liquid receiver. The liquid receiver shall be in accordance with Data-L;ist PZ 101 and shall have: a fuse plug as a safety device. 15 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-E-28968 Y4 779990b 02r17898 T W 3.3.12.1.10 Air filter. The a
30、ir filter shall be a All removable, cleanable type. It shall be an approved type as determined by label of the Undevriters Laboratories or the Factory Mutual Laboratories. material of the filters shall be corrosion-resistant and enclosed in a metal frame. 3.3.32.1.11 Outside surfaces. All outer surf
31、aces which make contact with air surrounding both the condenser and evaporator sections of the unit shall be insulated on their inside surfaces with 1/2-inch-thick chemically expanded cellular insulation conforming to MIL-1-1 6 56 2 3.3.12.1.12 Evaporator mn. The evaporator drain pan shall be coated
32、 on the inside with not less than L/lG-inch-thick layer of cork-impregnated, fungus-proof sealing compound. to make the evaporator pan watertight and permit proper flow of condensate. The compound shall be applied in order 3.3.12,L.13 Fresh air intake. The unit shall be designed to have a fresh air
33、intake, manually controllable from O to 50 percent of total cubic feet per minute ( Each air conditioner 3.3.12.1.15 Life expectancy. The life expectancy of the air conditioner shall be at least 3,000 hours of operation without any maintenance other than cleaning of the air filters. 3.3.12.1.16 Nois
34、e level. The noise level produced by the two air conditioners combined shall not exceed 72 decibels (dB) at any pint within the shlter in SSC. in the ESC, with four air conditioners running, the noise level produced shall not exceed 72 dB at any point within the shelter. 16 Provided by IHSNot for Re
35、saleNo reproduction or networking permitted without license from IHS-,-,-MIL-E-27b 47 777770b 0247877 L MIL-E-28968 (MC) 3.3.12.1.17 Control system. Control over the air conditioning unit will be maintained by an adjustable remote bulb type thermostat having its selector dial mounted on the lower pa
36、rt of the air conditioning unit. Two additional conveniently located selector switches will enable the unit to be switched from automatic to manual operation of compressor and ventilating blower. The air conditioner compressor motor shall run continu- ously to reduce surges on the power lines. 3.3.1
37、2.1.18 Power requirements. Air conditioning unit power requirements shall be 120/208, alternating current volts (Vac) 510 percent, 3-phase, or equal TK- 8 7 /U Scout Wilton Tool Co, 535, or equal Superior Electric Co., 136B.3, or equal Superior Electric CO., 2HL 15 UK-3Y, or equal Telex, Inc., MR-6, or equal Weller, D 550,.or equal Wckes, Model 768, or equal .Wckes, or equal - 1/ Tropicalization in accordance with 3.2.2 30 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
