support on direct exchange basis. TM 11-6140-203-23
provides instructions for the proper maintenance of
aircraft nickel-cadmium batteries.
If the battery being replaced
overheating or overcharging (e.
g., fumes or vapor coming from
the vent tubing, free electrolyte is
present inside the case, etc.)
checked/adjusted in accordance
(2) Cleaning. Clean battery in accordance
with TM 11-6140-203-23. Clean battery compartment in
accordance with TM 1-1500-344-23.
b. Relays. Army aircraft use generator field,
reverse current, bus control, non-essential bus, and
electronic/solid state relays. Relays are used for remote
control of circuits carrying heavy currents. Two relay
types are shown in figure 3-8.
(1) Inspection. Inspect contact points for
(2) Replacement criteria. Replace when
contact points are corroded beyond depth of pin plating.
c. Inverters. Inverters, as shown in figure 3-9, are
sometimes used to convert aircraft dc power to ac
power. The ac power is mainly used for instruments,
radios, radar, lighting, weapons, and other accessories.
(1) Types. There are two basic types of
inverters: the rotary and the static. Either type can be
single phase or multiphase.
(2) Inspection. Use the applicable aircraft
General inspection procedures are as follows:
(b) Inspect electrical connectors for
broke pins or cracked connector inserts.
(c) Check for bonding and security
(d) Check for faulty operation.
(3) Adjustment. Usually, no adjustments
Figure 3-8. Typical Relays
Change 3 3-14