13–10–613 Page 21
FIGURE 4–5 – SHUTTLE VALVE
Solenoid Valves IVC and IVO – These valves control
position of the inlet valve in response to signals from
the “AUTO SENTRY
” controller. With both valves
de–energized, the normally open IVC valve allows con-
trol pressure to the inlet piston to close the valve. If IVC
only is energized, the inlet valve is held in its current
position. If both valves are energized, control pressure
is relieved from the inlet piston to allow the valve to
open.
Pressure Regulator – The pressure regulator is used
to supply a constant and low control pressure to pre-
vent damage to the inlet valve from “slamming.” The
regulator should be set for 25–30 psig.
Shuttle Valve (FIGURE 4–5) – Also known as a
double check valve, the shuttle valve is a device which
will take two (2) supply signals and allow the one with
the highest pressure to pass through. The shuttle valve
is used to provide control air pressure from either the
reservoir or plant air system, as required during differ-
ent operating conditions.
Purge Air Valve – The purge valve is a normally closed
two–way air actuated valve that admits purge air from
the final discharge manifold to the compressor to coun-
teract the oil knock that occurs in oil–flooded rotary
screw compressors when they are completely un-
loaded with pressure in the oil reservoir. This valve is
controlled by the same control pressure which controls
the inlet valve.
Turn Valve (Electra–Saver only) (FIGURE 4–6)– The
turn valve is a helical valve which, when rotated, opens
and closes a series of ports cast into the compressor
cylinder. When these ports are open, they direct some
of the air which would otherwise be compressed back
to the inlet, reducing both capacity and power con-
sumption.
Turn Valve Actuator (Electra–Saver only)
(FIGURE 4–7) – The turn valve actuator is a rotary rack
and pinion device which positions the turn valve ac-
cording to system demand. Filtered oil from the com-
pressor sump is directed to the outboard end of the two
actuating cylinders to move the rack and rotate the
valve. Located on the ends of the cylinders are adjust-
ing screws which limit the travel of the actuator. The
adjusting screw on the top adjusts the open position of
the turn valve; the bottom adjusting screw adjusts the
full closed (full load) position of the valve. The full load
position of the actuator may be checked by removing
the adjusting screw at the unloaded end of the actuator
(top of the compressor) and using a rod to push the pis-
tons to the full load position. The rod must be clean and
free of burrs and scale. Take care not to scrape the cyl-
inder walls when moving the pistons.
Solenoid Valves TVC and TVO (Electra–Saver only)
– These valves control the position of the turn valve in
response to signals from the “AUTO SENTRY
” con-
troller. With both valves de–energized, equal pressure
is applied to both ends of the actuator to hold it in its
FIGURE 4–6 – TURN VALVE CONTROL
Содержание ELECTRA-SAVER EAY
Страница 14: ...13 10 613 Page 6 DECALS 206EAQ077 212EAQ077 218EAQ077 211EAQ077 207EAQ077...
Страница 15: ...13 10 613 Page 7 DECALS 216EAQ077 217EAQ077 222EAQ077 221EAQ077 208EAQ077...
Страница 32: ...13 10 613 Page 24 FIGURE 4 8 CONTROL SCHEMATIC COMPRESSOR AT FULL LOAD 204EAY797 B Ref Drawing...
Страница 35: ...13 10 613 Page 27 FIGURE 4 11 WIRING DIAGRAM 202EAY546 Ref Drawing...
Страница 55: ......
