A-A-52551 Starter-Generator: 300 Ampere, 28 Volts, Direct CurrentThis CID covers the requirements for a 300 ampere (A), 28 volt (V), direct current (dc) starter-generator, referred to herein as "generator". This dual purpose unit is belt driven with open construction and not submersible. The generator is used on military motor vehicles and on other equipment to start the gasoline engine connected to it and to generate dc energy for lighting, battery charging, and other purposes.

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A-A-52551A

2.3.4 Temperature.

2.3.4.1 High temperature. Generator shall evidence no thrown solder, thrown impregnating compound, damaged insulation, raised armature windings, raised commutator bars or other damage when operated at average speed, rated output, and ambient temperature of 160° ± 5°F for 4 hours. Generator frame temperature shall not exceed 320F. Prior to operation, generator shall be stored for 24 hours in an ambient temperature of 160° ± 5°F. Generator shall subsequently meet the requirements of 2.3.1 at the performance checkpoint in figure 1.

2.3.4.2 Low temperature. Generator shall meet the requirements in 2.3.4.1 except that the ambient temperature shall be -65° + 5°F.

2.3.5 Dielectric strength. Insulation shall evidence no loosening, cracking, charring, burning, smoking, or reduction in dielectric strength when subjected to a ground test of 500 volts root-mean-square (rms) at a frequency of 60 Hertz (Hz), applied for one minute. The potential shall be applied to the armature and field terminals with the ground brush raised off the commutator and with the field ground terminal disconnected.

2.3.6 Shock resistance. Generator shall evidence no breakage, loosening of parts, abrasion, or other physical damage when subjected to three shock pulses conforming to figure 2, applied in both directions along each of three orthogonal axes. Generator shall subsequently meet the requirements of 2.3.1 at the performance checkpoint in figure 1.

FIGURE 2. Sawtooth shock pulse configuration.