Section III. UNIT PREVENTIVE MAINTENANCE CHECKS AND
This section details the Preventive Maintenance Checks and Services (PMCS) required for the PDU. PMCS is a
scheduled, step-by-step inspection and service of the PDU and PDU components. Its purpose is to keep the PDU in
good condition, and to identify and correct problems before costly and time-consuming repairs are needed.
Unit PMCS should be performed at the intervals shown below:
a. Do your (M) preventive maintenance monthly (every month).
b. Do your (S) preventive maintenance semiannually (every 6 months).
Do your (A) preventive maintenance annually (once every year).
Use DA Form 2404, Equipment Inspection and Maintenance Worksheet, to record periodic maintenance services
performed and faults corrected. The item number on the DA Form 2404 must be the same as the item number of the
PMCS. For information on maintenance forms and records, see DA Pam 738-750.
Nuts, bolts, and screws: When torquing bolts or nuts, begin with larger-diameter or inner bolt first and tighten to the
specified torque diagonally, unless a particular sequence is specified. After reassembly, check all parts for proper
installation and operation.
Class III leaks are cause to remove equipment from service until repair action is taken.
Seepage of fluid (as indicated by wetness or discoloration) not great enough to form drops.
Leakage of fluid great enough to form drops but not enough to cause drops to drip from item being
Class III Leakage of fluid great enough to form drops that fall from item being checked/ inspected.