ARMY TM 10-4610-309-14
MARINE CORPS TM 10802A-14/1
TACTICAL WATER PURIFICATION SYSTEM (TWPS)
0003 00
DESCRIPTION AND THEORY OF OPERATION
THEORY OF OPERATION
Air Compressor and PSL/PSH-901 Assembly
During operation the belt-driven, three-stage compressor is powered by a five horsepower, 416 vac, 60Hz
motor (see Figure 16). Low-Pressure Switch PSL-901 turns the compressor motor on through the PLC
(programmable logic controller) in the OCP (operator control panel) when air pressure falls below 800
psig. High-Pressure Switch PSH-901 turns the compressor motor off through the PLC when pressure
exceeds 950 psig. PSL-901 and PSH-901 are parts of a single pressure switch device. A safety valve on
the air compressor first stage head and on the intermediate filter protect the 1st and 2nd stage compressor
valves from over pressurization. Automatic Drain Valve XV-910, which is located between the second
and third stages of the compressor and which is controlled by the PLC, removes oil and water from the
compressor intermediate filter at 15-minute intervals. Temperature Switch TSH-901 shuts down the
compressor if the compressor third-stage temperature is too high.
TEMPERATURE SWITCH TSH-901
LOW PRESSURE SWITCH PSL-901 /
HIGH PRESSURE SWITCH PSH-901
INTERMEDIATE
ASSEMBLY
FILTER
COMPRESSOR
MOTOR
SAFETY VALVE ON
INTERMEDIATE FILTER
AUTOMATIC
DRAIN VALVE
XV-910
SAFETY VALVE ON
ST
COMPRESSOR 1 STAGE HEAD
Figure 16. Air Compressor Assembly and High and Low Pressure Switch Assembly.
0003 00-20
