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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)

3.4.1.2.2 Color of laminates. Laminates shall be furnished in the natural color, except polyester laminates may

be furnished in tan or red.

3.4.1.3 Molded plastics.

3.4.1.3.1 Molded thermosetting plastics. Molded thermosetting plastics shall generally be used in electrical

equipment where a rigid dielectric is needed and where the form or shape is such that fabrication of the part out of

sheet stock is too costly, or the part is too complex in design. For molded parts, the following conditions shall be

met:

a. The molding compound shall be of the type shown in table VII or equivalent meeting the specified

requirements.

b. The molding compound shall meet the minimum requirements for toxicity (see 3.3.1.1), flame resistance

(see 3.3.1.9), and arc resistance (see 3.4.1.1).

The molding compound shall meet the mechanical and electrical requirements of each application.

TABLE VII. Molding compounds (glass fiber reinforced).

Applicable

Compounds

Type

Max. temperature, �F (�C)

document

Polyester glass

MAI-60

ASTM D5948

266 (130)

Polyester glass

MAI-30

ASTM D5948

266 (130)

MAT-30 1/

Polyester glass

ASTM D5948

266 (130)

Melamine glass

MMI-30

ASTM D5948

266 (130)

Melamine glass

MMI-5

ASTM D5948

266 (130)

Diallyl ortho-phthalate

SDG-F

ASTM D5948

311 (155)

Diallyl ortho-phthalate

GDI-30F

ASTM D5948

311 (155)

Diallyl iso-phthalate

SIG-F

ASTM D5948

356 (180)

Diallyl iso-phthalate

GII-30F

ASTM D5948

356 (180)

Silicone mineral 2/

MSG

ASTM D5948

392 (200)

Silicone glass 2/

MSI-30

ASTM D5948

392 (200)

Epoxy glass

GEI-5, -20, -100

ASTM D5948

266 (130)

NOTES:

Mandatory for high voltage application (2,000 V or higher).

See 3.3.1.4 for restrictions on the use of silicone.

3.4.1.3.1.1 Colors of thermosetting plastics. Thermosetting molding compounds for low voltage application

shall be furnished in a gray color, with an approximate match to number 26307 (semigloss) or 16307 (gloss) of

FED-STD-595. Thermosetting molding compounds for high voltage application, rated at 2,000 V or higher, shall be

furnished in a red color to match number 11120 or 11140 of FED-STD-595.

3.4.1.3.2 Thermoplastics. In general, thermoplastics shall not be used in any molded part unless allowed by the

individual equipment specification as specified (see 6.2). When the application is such that only a thermoplastic

material can be used, then the molding compounds shall be selected in accordance with table VIII or equivalent

meeting the specified requirements.