Gardner Denver ELECTRA-SAVER ETY99A, Руководство пользователя

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13–13–600 Page 24
System Pressure Transducer – This transducer is
connected after the minimum pressure valve. It con-
verts the pressure in the plant air system into an electri-
cal signal for use by the “AUTO SENTRY
” controller
for modulation and control.
Reservoir Pressure Transducer – This transducer
is connected to the coolant system. Its signal is used
to prevent loaded starts, monitor oil pressure, and mon-
itor the condition of the separator.
Air Filter Vacuum Switch – This switch is used to
monitor air filter condition and alert the user if the filter
requires service or replacement.
Discharge Thermistor – This sensor is located di-
rectly in the compressor discharge. Its signal is used
to monitor compressor temperature and shut down the
compressor if a coolant problem is detected.
Reservoir Thermistor – This sensor is located in the
reservoir / separator housing and is used to monitor
temperature and shutdown the compressor if tempera-
ture problems occur at the separator.
Optional Switches – The “AUTO SENTRY ” control-
ler has one additional input available for dealer or user
installed optional shutdown switches. If the contact is
opened, the compressor will be shut down, and will dis-
play a user selectable message (refer to unit setup ad-
justments for list of messages).
Emergency Stop Pushbutton – This is a maintained
pushbutton, and removes power from the controller
outputs regardless of controller status. It is located on
the upper section of the panel, next to the keypad. This
should be used for emergency purposes only – use the
keypad [STOP/RESET] for normal controlled stopping.
Automatic restarting or electrical
shock can cause injury or death.
Open, tag and lockout main discon-
nect and any other circuits before
servicing the unit.
Turn Valve – 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 capac-
ity and power consumption.
FIGURE 4–6 – TURN VALVE CONTROL
Turn Valve Actuator (FIGURE 4–7, page 25) – The
turn valve actuator is a rotary rack and pinion device
which positions the turn valve according to system de-
mand. Filtered oil from the reservoir is directed to the
outboard ends of the two actuating cylinders to move
the rack and rotate the valve. Located on the end of the
cylinders are adjusting screws which limit the travel of
the actuator. When looking at the rear of the compres-
sor, the adjusting screw on the bottom of the compres-
sor adjusts the fully closed (full load) position of the
valve. The full load position of the actuator may be
checked by removing the adjusting screw at the un-
loaded end of the actuator (top of the compressor) and
using a rod to push the pistons to the full load position.
The rod must be clean and free of burrs and scale.
Take care not to scrape the cylinder walls when moving
the pistons.
Solenoid Valves TVC and TVO – These valves con-
trol position of the turn valve in response to signals from
the “AUTO SENTRY
” controller. With both valves
de–energized, equal pressure is supplied to both sides
of the actuator to hold it in its current position. If TVC
only is energized, the bottom of the turn valve actuator