Bell OH-58A Technical Manual page 210

TM 55-1520-228-BD
ELECTRICAL AND AVIONICS SYSTEM
11-22. BUS BARS.
GENERAL INFORMATION: Rigid bus bars are
used in the power distribution circuits
of the aircraft. Replace damaged bus
bars with copper or brass strips of wire
of the same or higher cross-sectional
area. Use aluminum only when replacing
aluminum bus bars since it makes
unrealizable contact with other metals.
Repaired bus bars will
LIMITATIONS:
have a somewhat higher resistance than
the original circuit and a higher than
normal voltage drop may occur.
Temporary repair.
PERSONNEL/TIME REQUIRED:
. 2 Soldiers
. 2 Hours
MATERIALS/TOOLS REQUIRED:
. Drill and Bit
. Nuts, Bolts, Flat Washers, Lock
Washers
. Tape (item 49, Appx C)
. Brush, Wire
. File
. Hacksaw
PROCEDURAL STEPS:
1. Cut a section of another bus bar to
use for splice.
2. Drill matching holes in bus bar
sections and splice, Figure 11-38.
3. Remove insulation from bus bar only
where needed. Insure contact surfaces
of cracked bus bar and splice are smooth,
and clean to reduce resistance. If
necessary, use tile and wire brush to
dress and prepare contact surfaces.
4. Install bolts and washers and
tighten. Insure no contact of bolts
with aircraft structure.
5. Insulate repair with tape or slit
a piece of insulating tubing, and wrap
around the repair and tie with string.
11-38
6. Same repair procedure
lengthen bus bars, Figure
7.
Record BDAR action taken. When
mission is complete, as soon as
practical, repair the equipment/system
using standard maintenance procedures.
11-23. BATTERY REPAIR, BB-476/A.
GENERAL INFORMATION: Nickel-Cadmium
(Ni-Cad) batteries consist of a number
of cells connected in series. Damage to
a cell which does not result in short
circuiting and destroying the battery.
The following procedure gives instruc-
tions for locating and removing bad
Ni-Cad battery cells and creating a
jumper around the bad cell.
WARNING
. Ni-Cad batteries use potassium
hydroxide, a strong caustic alkali,
as the electrolyte.
this electrolyte on your skin or
in your eyes. Use rubber gloves,
rubber apron, and protective
goggles when handling the elec-
trolyte. If accidental contact
with the electrolyte is made, use
ONLY clean water and immediately
(seconds count) flush contami-
nated areas. Continue flushing
with large quantities of clean
water and get medical attention
as soon as possible.
. If steam or spewing electrolyte
is observed or the battery is hot
to the touch, DO NOT ATTEMPT TO
remove from the aircraft imme-
diately.
CAUTION
Penetration of battery case by
small arms fire or shrapnel will
cause thermal runaway.
battery cells will overheat and
rupture, melt, or explode.
Exercise extreme caution when
repairing the battery.
can be used to
11-39.
Do not get
The