TM 5-2090-202-12&P
TM 2090-12&P/1A
f. Calibrate. To determine and cause corrections to be made or to be adjusted on instruments or test, measuring
and diagnostic equipment used in precision measurement. Consists of comparisons of two instruments one of which is a
certified standard of known accuracy, to detect and adjust any discrepancy in the accuracy of the instrument being
compared.
g. Install. The act of emplacing, seating or fixing into position an item, part, or module (component or assembly) in
a manner to allow the proper functioning of an equipment or system.
h. Replace. The act of substituting a serviceable like part, subassembly, or module (component or assembly) for
an unserviceable counterpart.
i. Repair. The application of maintenance services or other maintenance actions to restore serviceability to an
item by correcting specific damage, fault, malfunction, or failure in part, subassembly, module (component or assembly),
end item, or system.
j. Overhaul.
That maintenance effort (services/actions) necessary to restore an item to a completely
serviceable/operational condition as prescribed by maintenance standards (i.e., DMWR) in appropriate technical
publications. Overhaul is normally the highest degree of maintenance performed by the Army. Overhaul does not
normally return an item to like new condition.
k. Rebuild. Consists of those services/actions necessary for the restoration of unserviceable equipment to a like
new condition in accordance with original manufacturing standards. Rebuild is the highest degree of material
maintenance applied to Army equipment. The rebuild operation includes the act of returning to zero those age
measurements (hours/miles, etc.) considered in classifying Army equipments/components.
B-3. EXPLANATION OF COLUMNS IN THE MAC, SECTION II.
a. Column 1, Group Number. Column 1 lists group numbers, the purpose of which is to identify components,
assemblies, subassemblies, and modules with the next higher assembly.
b. Column 2, Component/Assembly. Column 2 contains the names of components, assemblies, subassemblies,
and modules for which maintenance is authorized.
c. Column 3, Maintenance Functions. Column 3 lists the functions to be performed on the item listed in column 2.
(For detailed explanation of these functions, see para. B-2.)
d. Column 4, Maintenance Level. Column 4 specifies, by the listing of a "work time" figure in the appropriate
subcolumn(s), the lowest level of maintenance authorized to perform the function listed in column 3. This figure
represents the active time required to perform the maintenance function at the indicated level of maintenance. If the
number of complexity of the tasks
B-2
