Air System Controls and Indicators. Figure 2-7 and Table 2-7 list the controls and indicators for the air system.
Table 2-7. Air System Controls and Indicators
Control or Indicator
Air Compressor ON/OFF
Energizes motor start/stop circuit at pressure switch.
Starts and stops compressor automatically at required pressures.
Compressor starts at 60 psi, and stops at 120 psi.
Provides safety relief if air pressure in tank goes above 150 psi.
Tank Drain Valve
Provides tank moisture drain.
Air System Isolation Valve
Provides isolation of air system.
Air Pressure Gauge
Indicates air pressure in tank.
Air Service Valves
Provides service access to air system. Two stopcock valves are
located on roadside wall, one on curbside wall, and one in each