TM 11-7021-202-12
Section IV. OPERATION UNDER UNUSUAL CONDITIONS
2-8.
OPERATION IN UNUSUAL WEATHER
It may be necessary to operate the processor under abnormal conditions where extreme
cold, heat, humidity, moisture, or sand and dust conditions prevail. Instructions for
minimizing the effects of these unusual operating conditions are given in the following
subparagraphs.
a. Arctic Climates. Subzero temperatures and climatic conditions effect the proper
operation of the equipment. Handle the equipment carefully. Parts, especially plastics and
wiring insulation, become brittle at subzero temperatures. When equipment is exposed to
cold air, moisture will condense on it. Dry the equipment thoroughly. Equipment should be
operated in a heated environment (table 1-2).
b.
Tropical Climates. In tropical climates, the high relative humidity causes
condensation of moisture on the unit whenever equipment temperature becomes lower than
that of the surrounding air (table 1-2). Adequate ventilation will minimize this condition.
Check frequently for fungus or moisture on the unit. To remove fungus or moisture, use a
lint-free cloth and alcohol.
c. Desert Climates. The main problem arising in desert operation is sand, dust, or
dirt getting into the equipment. Keep the equipment as free of foreign material as possible.
2-9.
EMERGENCY PROCEDURES
In the event of a power outage, data currently stored in the processor's semiconductor
memory may be lost. The RAM chips used in the semiconductor memory do not hold
information in the event of a power failure; however, a battery backup unit can be connected
to the processor. Battery backup power is connected at J6 on a semiconductor-based
processor and can maintain the memory for approximately 60 minutes (table 1-3).
The magnetic nature of the core memory module allows it to hold current instructions and
operating data, unchanged, in the event of a power outage. No backup battery is required
for processors with core memory.
If an emergency condition occurs, shut down main power source to the equipment. Refer to
the applicable system manual for additional emergency shut-down procedures.
2-11/(2-12 Blank)
