GENERAL SUPPORT MAINTENANCE INSTRUCTIONS
SECTION I. GENERAL
5-1. Scope. This chapter provides general support maintenance instructions for the power distribution box.
Troubleshooting and test procedures in this chapter supplement maintenance instructions provided in TM 32-
5865-012-20 by using additional test equipment, tools, and materials available to general support maintenance.
5-2. Organization. This chapter contains tables of reference data and measurements that are made on the
power distribution box to determine proper operation. This chapter also references the tools and test
equipment required and provides a troubleshooting procedure. In addition, the chapter provides maintenance
and test procedures to the component level for general support maintenance.
5-3. Measurements and Data. Input power is 115 V ac, three-phase, 400-Hz. The three voltage phases are
derived from a Y-wound transformer. Each voltage phase is measured between one leg of the Y and the
center ac neutral. A chassis ground is also provided. Measurements made between a voltage phase line and
chassis ground are not valid.
Because of the power source arrangement, ac neutral and ground are not
the same. It is possible for voltage potentials to exist between ac neutral
and ground. These potentials may cause shock and personal injury.
Remove power before making resistance checks.
a. AC Power Resistance Checks. Table 5-1 lists measurements and data for the ac power input at
connector J1. The data is used for resistance checks.