MIL-DTL-917 Electric Power Equipment, Basic Requirements ForThis specification covers the basic requirements applicable to the design, materials, and construction of naval shipboard electric power equipment \(exclusive of communication equipment, information technology \(IT\) equipment, and combat systems [fire control and weapons control equipment]\). Unless otherwise specified herein, the electric equipment developed for shipboard use under the requirements of this specification are limited to a maximum 450 volt \(V\) alternating current \(AC\) and a maximum 1,000 V direct current \(DC\). This equipment is intended for use on surface and submarine naval vessels \(see 6.2\).

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MIL-DTL-917F(SH)

TABLE I. Temperature ranges ambient.

Service

Operating

Non-operating

Exterior shipboard

-18.4 �F (-28 �C) to 149 �F (+65 �C)

-40 �F (-40 �C) to 167 �F (+75 �C)

32 �F (0 �C) to 122 �F (+50 �C) 1/

Interior shipboard

-40 �F (-40 �C) to 167 �F (+75 �C)

NOTE:

The interior shipboard operating range for non-militarized equipment which can fit through

shipboard hatches and can be removed in 1 man-day can have an allowable temperature range

of 32 �F (0 �C) to 107 �F (+40 �C).

3.2.13.2 Humidity. Equipment specified in the individual equipment specification shall conform to the

requirements of MIL-STD-202, Test Method 103B, for humidity (see 6.2). Equipment shall operate satisfactorily

during and subsequent to exposures to relative humidities ranging up to 95 percent for both continuous and

intermittent periods, including conditions wherein condensation occurs on the equipment.

3.2.14 Shock and vibration.

3.2.14.1 Shock. Equipment specified in the individual equipment specification shall conform to the

requirements of MIL-S-901 for high-impact (H.I.) shock as specified (see 6.2).

3.2.14.2 Vibration. Equipment specified in the individual equipment specification shall conform to the

requirements of MIL-STD-167-1 for vibration as specified (see 6.2).

3.2.15 Equipment mounting. For equipment required to meet the H.I. shock requirements of MIL-S-901, the

following mounting requirements shall be as specified (see 6.2):

a. Equipment shall be designed for mounting with Grade 5 or stronger bolts or capscrews in accordance with

MIL-DTL-1222.

Size of mounting holes shall be as specified in table II.

TABLE II. Size of mounting holes.

Nominal bolt diameter

Max. diameter of hole

Nominal bolt diameter plus 1/32 inch

� inch and smaller

Nominal bolt diameter plus 1/16 inch

Larger than � inch

Equipment may be designed to use fitted (also known as body-bound) bolts for mounting (see 6.2).

3.2.16 Electromagnetic interference (EMI) general requirements. The equipment shall comply with the EMI

requirements specified in MIL-STD-461 for surface ship, below deck and submarine, internal to pressure hull,

installations. Detailed design and testing requirements shall be included in the individual equipment specification as

specified (see 6.2).

3.2.17 DC magnetic field environment. Shipboard equipment shall comply with the static magnetic field

environmental interface constraints in accordance with DOD-STD-1399-070 as specified (see 6.2).

3.2.18 Magnetic field reduction. When the individual equipment specification requires that the magnetic field

or magnetic signature of the equipment be minimized, the ferrous, stray, and eddy current fields shall be minimized

in accordance with DOD-STD-2143 as specified (see 6.2).

3.2.18.1 Ferrous field source. The equipment shall be designed in accordance with DOD-STD-2143 for a

Class 1 magnetic field source.

3.2.18.2 Eddy current field source. The equipment shall be designed in accordance with DOD-STD-2143 for a

Class 2 magnetic field source.