Table 4-6.—AHT-63 Control Panel Controls and Instruments Fig. 7-14 Index No. Instrument Description Function 1 Panel Lights Shielded type, 28V, s.c. Provides illumination for bayonet base, clear bulb. control panel. 2 HIGH PRESSURE FILTER Panel mounted, press-to-test Indicates when 3-micron Indicator Light with red lens; Bulb, 28V, s.c. high pressure filter element bayonet. requires service. 3 PUMP CASE FILTER HIGH Panel mounted, press-to-test Turns on when pump case DIFFERENTIAL pilot light with red lens; filter requires service. PRESSURE Indicator Light Bulb, 28V, s.c. bayonet. 4 LOW PRESSURE FILTER Panel mounted, press-to-test Turns on when low pressure Indicator Light pilot light with red lens; filter element requires Bulb, 28V, s.c. bayonet. servicing. 5 FLUID TEMPERATURE Panel mounted, press-to-test Turns on when fluid WARNING Indicator Light pilot light with red lens; temperature increases to trip Bulb, 28V, s.c. bayonet. setting of thermoswitch (160°F). 6 STOP Switch Red mushroom pushbutton Used to stop electric drive switch. motor. 7 PUMP COMPENSATOR Knurled knob with knurled Adjusts the pressure at Control locking nut. which compensation occurs. 8 FLUID TEMPERATURE Dial indicating; 30 to 220°F; Indicates temperature of GAUGE with adjusting screw hydraulic fluid going to inlet (Recalibrator). of high pressure pump. 9 PRESSURE SELECTOR Four position, 3-way selector Provides selection of boost VALVE valve lever handle. pump inlet, high pressure pump inlet, or return line readings on compound gauge; 4th position (OFF) is for calibration of gauge. 10 COMPOUND GAUGE Compound gauge; 0 to 30 in. Indicates back pressure or Hg vacuum and 0 to 200 psi suction in low pressure with zero adjusting screw return line, inlet to boost (Recalibrator). pump, and inlet to high pressure pump. 11 GAUGE TEST Fittings Cap and bulkhead nut. Used for testing and calibrating compound and high pressure gauges. 4-32