CONTROLS AND INSTRUMENTS (cont)

ARMY TM 9-6115-464-12 AIR FORCE TO 35C2-3-445-1 NAVY NAVFAC P-8-624-12 ad. ae. af. ag. ah. ai. aj. ak. al. am. an. ao. ap. Frequency Adjust Rheostat (29, Figure 2-1). The frequency adjust rheostat increases or decreases the frequency output of the tactical precise generator sets. NOTE The frequency adjust rheostat is functional on the precise generator sets only. Circuit Breaker Switch (30, Figure 2-1). The circuit breaker switch is a three position, momentary-on-mo- mentary-off toggle switch. It opens and closes the main load contactor. The circuit breaker switch is in the center position during normal operation. Circuit Breaker Indicator (31, Figure 2-1). The circuit breaker indicator is a press-to-test indicator light with a yellow lens. It illuminates when the main load contactor is closed. Start-Run-Stop Switch (32, Figure 2-1). The start-run-stop switch is a three position toggle switch, used to start and stop the generator set. Engine Primer Switch (33, Figure 2-1). The engine primer switch is a single pole, two position toggle switch. When the START-RUN-STOP switch is in the START position and the ENGINE PRIMER switch is moved to the ON position, and then released, it actuates the ether starting aid. During operation, the switch remains in the OFF position. Running Time Meter (34, Figure 2-1). The running time meter is a time totalizing meter which indicates total engine operating time in hours and tenths of hours. Battery Charging Ammeter (35, Figure 2-1). The battery charging ammeter is a dial indicator type gauge which measures dc current flow to and from the battery. It is calibrated in 1 ampere increments from -10 to +20. Normal indication of the meter is dependent upon the state of charge of the battery. A low charge such as exists immediately after engine starting, will result in a high reading. When enough charge has been restored to the battery the indicator should move near 0. Fuel Level Gauge (36, Figure 2-1). The fuel level gauge is a liquid quantity indicator gauge which is calibrated 1/4 increments of tank quantity from E (empty) to F (full). It indicates the level of fuel in the main fuel tank. Engine Oil Pressure Gauge (37, Figure 2-1). The engine oil pressure gauge is a dial indicator type gauge which is calibrated in psig from 0 to 60. It measures engine lubrication oil pressure. Normal indication is from 20 to 55 psig. Coolant Temperature Gauge (38, Figure 2-1). The coolant temperature gauge is a dial indicator type gauge which is calibrated in degrees Fahrenheit from 120 to 240. Normal operation indication is 170°F (76.7°C) to 200°F (93.3°C). Fuel Selector Valve (Figure 1-5). The fuel selector valve is a three-way valve. It selects either the integral tank or the auxiliary source for fuel. It also serves as a shutoff valve. Frequency Selector Switch (Figure 1-4). The frequency selector switch is a two position, positive locking toggle switch. It is located on the precise relay assembly. The switch changes the generator circuit from 60 Hz to 50 Hz operation. Most applications of the generator set will require that this switch be placed in the 60 Hz position. NOTE The frequency selector switch is used on the 50/60 Hz Tactical Precise generator sets only. Shutter Control Assembly. The shutter control assembly is a thermostatically controlled assembly. It is lo- cated at the bottom left of the radiator assembly. The assembly retains the shutter louvers (located behind the grille) in the dosed position until the engine coolant has reached normal operating temperature. 2-3