4-19
Figure 4-14.—Typical local dehydrator interface.
Local dehydrators depend on the ship's lp air for an inlet supply, while the local compressor-
dehydrators can operate independently of the ship's air supply. Some units of electronic equipment that
have local dehydrator units are pressure interlocked within the dehydrator unit. When the outlet air
pressure is below a set value, the interlock prevents the equipment from going to a full OPERATE
condition. When the central dry-air system is used, the pressure interlock is bypassed.
Some radars provide a tank of nitrogen as an emergency source that can be connected in place of dry
air. Special safety precautions must be taken when you handle compressed gases because of the
possibility of explosion. Nitrogen does not support life; when released in a confined space, it can cause
asphyxiation.
Q16. What is the normal source of dry air for a radar system?
Q17. What is the major difference between the electronics dry-air branch and the vital service lp air
main?
Q18. What is the air control panel designed to control?
COOLING SYSTEMS
Radar equipment, particularly the high-power transmitters, generate large amounts of heat. This heat
must be dissipated to prevent damage to the equipment and to prevent erratic circuit operation. Most radar
equipment rooms have high-capacity air-conditioning systems to control the ambient room temperature;
