Sullair TS20C, Руководство пользователя

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TS20C USER MANUAL SECTION 2
20
Supervisor Controller will automatically set the
frequency range based on the selected pressure. For
explanatory purposes, this description will apply to a
compressor with an operating pressure of 100 psig
(6.9 bar). A compressor with any other pressure
range would operate in the same manner except
stated pressures.
START MODE—0 – 50 PSIG (0 TO 3.5 BAR)
When the Supervisor™ Controller ( START )
button is depressed, the VSD ramps the motor to full
speed and the sump pressure will quickly rise from 0
to 50 psig (0-3.4 bar). During this period, the solenoid
valve is closed, the inlet valve is fully open and the
air-end delivers full capacity to the sump tank. The
rising compressor air pressure is isolated from the
service line in this phase by the minimum pressure
valve set at approximately 50 psig (3.4 bar).
FULL LOAD MODE—50 TO 100 PSIG (3.4 TO 6.9
BAR)
When the compressed air pressure rises over 50
psig (3.4 bar) the minimum pressure valve is opened
allowing compressed air to flow into the service line.
From this point on the line pressure is continually
monitored by the Supervisor™ Controller, which
controls the variable speed drive. The solenoid valve
remains closed with the inlet valve fully open running
at 100 psig (6.9 bar) or below.
VARIABLE SPEED DRIVE PART LOAD CONTROL
If less than rated capacity of compressed air is being
used, the service line pressure will rise above 100
psig (6.9 bar). Consequently, the Variable Speed
Drive will begin to decelerate the motor, thereby
reducing the output capacity to match demand. The
drive will continuously adjust the motor speed
(accelerate or decelerate) to maintain a line pressure
of 100 psig (6.9 bar). In this mode the VSD will
operate within the appropriate frequency range
determined by the Supervisor™ Controller.
MODULATING MODE WITH SPIRAL VALVE:
As demand decreases, the variable speed drive
reduces motor speed to maintain the set point pres-
sure. When the speed approaches the minimum
setting, a solenoid valve opens feeding air pressure
to the spiral valve actuator. This in turn expands the
diaphragm and engages the pinion mounted on the
spiral valve shaft assembly, resulting in a rotary
motion and full opening of the spiral valve, effectively
reducing the rotor length by 50%. Excess air will be
returned back internally to the suction side of the
compressor unit. In this mode, the VSD will modulate
the motor speed within a specified range to maintain
the set point pressure as follows:
Increasing demand condition:
If demand increases, the VSD increases the motor
speed until the set point pressure is achieved. If set
point pressure is not achieved while at maximum
speed, the controller will close the spiral valve,
thereby eliminating internal air bypass.
Consequently, the VSD will regulate the motor speed
to achieve the set point pressure.
Decreasing demand condition:
While the spiral valve is open, if demand continues to
decrease the VSD will reduce the motor speed until
the set point pressure is achieved. This action will
continue until the minimum speed is reached. When
the system pressure reaches 106 psig (7.3 bar), or
alternatively set unload pressure, the compressor
unloads, or turns off.
UNLOAD MODE- IN EXCESS OF 106 PSIG (7.3 BAR)
When a relatively small amount or no air is being
used, the service line pressure continues to rise.
When it exceeds 106 psig (7.3 bar), or alternatively
set unload pressure, the Supervisor™ control system
de-energizes the solenoid valve allowing sump air
pressure to be supplied directly to close the inlet
valve. Simultaneously, the solenoid valve sends a
pneumatic signal to the blow down valve. The blow-
down valve opens to the atmosphere, reducing sump
pressure. The check valve in the air service line
prevents line pressure from returning to the sump.
The compressor will shut down after the unload time
setting expires if programmed (the default setting is
zero [0] seconds for an immediate shutdown upon
unload).
When the line pressure drops to the low setting
pressure of 100 psig (6.9 bar) The Supervisor™
Controller starts the motor and energizes the sole-
noid valve which closes the blow down valve. The re-
energized solenoid valve prevents line pressure from
reaching the inlet control valve, thereby allow- ing it
to fully open.
Automatic Operation
For applications with varied periods of time when
NOTE
This operation does not have inlet modula-
tion.)