2205B0JE-DA-J-N_2014.05.
4 Compressor and Package Operation
Screw Compressor J-series
4.1 Adjustment before Test Operation
4-1
4 Compressor and Package Operation
4.1
Adjustment before Test Operation
The unloader slide valve and variable Vi valve must be set by the controller before test operation.
4.1.1 Adjustment of Unloader Slide Valve and Variable Vi Slide
Valve
Before test operation, make sure to perform a set-up that allows the controller to learn unloader slide
valve positions from the 0% to 100%(indicated load)
and variable Vi valve positions from the 2.5 to 5.0.
During the setup, make sure to operate the oil pump only. Turn off the main power
for the compressor motor.
During the setup, make sure to keep the internal pressure of the compressor less
than 1.5 MPa (gauge pressure).
After the setup operation, equalize pressure by opening the suction stop valve
slowly in the package. After opening the suction stop valve, make sure that the
motor main power is off and then turn the compressor driving shaft manually.
1.
Close the suction stop valve of the package.
2.
Confirm that the internal compressor pressure is less than 1.5MPa (gauge pressure). If the
pressure in the compressor is high, setup work of the Vi slide valve becomes difficult to perform
accurately.
3.
To check the unloader solenoid valve operation, start the oil pump and adjust the pressure.
Set the oil pump discharge pressure 0.2 MPa (+/-0.05 MPa) higher than the oil pump suction
pressure.
4.
Using the controller manually, press the increase button of the unloader solenoid valve to increase
the load of the unloader slide valve and check if the indicator needle moves toward the 100%
point.
5.
If the indicator needle moves in the increasing direction, the unloader solenoid valve wiring is
correct.
6.
If the indicator needle moves reversely or does not move, check the unloader solenoid valve
wiring.
7.
Next, operate the variable Vi slide valve to the L-Port position using the controller and check the
variable Vi slide valve moving direction on the controller display.
8.
If the variable Vi slide valve moves to the L-Port direction, the variable Vi solenoid valve wiring is
correct. If it does not move or moves in the reverse direction, check the wiring.
9.
If the unloader slide valve and variable Vi slide valve move in the correct directions respectively,
execute the initial set up mode for the unloader slide valve and the variable Vi slide valve by the
controller.
10.
The oil pump automatically starts and the unloader slide valve and variable Vi slide valve
automatically move in increasing direction and decreasing directions to allow operational position
check.
With these steps, the initial adjustment for the unloader slide valve and the variable Vi slide valve is
completed.
