Emerson Vilter VSG128, Installation, Operation And Service Manual

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Section 4 • Operation
HPLD Single Screw Compressor • Installation, Operation and Service Manual • Emerson • 35391HP
If the compressor is in the automatic mode, it will now
load and unload in response to the system demands, at
the volume ratio specified by the plug.
Stopping the compressor unit can be accomplished a
number of ways. Any of the safety setpoints will stop the
compressor unit if an abnormal operating condition exists.
The compressor unit “On-Off” or stop button will turn
the compressor unit off as will the low pressure setpoint.
If there is a power failure, the compressor unit will stop.
Then the master control button (the white button/light)
will need to be pressed first.
• If the manual start on power failure option is selected
(see appropriate controller instruction manual),
restarting from this condition is accomplished by
pushing the reset button to insure positive operator
control.
• If the auto start on power failure option is selected
(see appropriate controller instruction manual), the
compressor unit will start-up after a waiting period.
Safety Setpoints
For a more detailed explanation of all safety setpoints,
check the controller instruction manual.
1. Oil Pressure
Low oil pressure differential stops the compressor
unit when there is an insufficient difference in pres -
sure between the oil manifold and suction.
2. Discharge Pressure
High discharge pressure cutout stops the compressor
unit, when the discharge pressure in the oil separator
exceeds the setpoint.
3. Suction Pressure
Low suction pressure cutout stops the compressor
unit when the suction pressure drops below the
setpoint.
4. Oil Filter Differential
High oil filter differential cutout stops the compressor
unit when the difference between the outlet and inlet
of the filter exceeds the setpoint.
5. Oil Temperature
The oil temperature cutout stops the compressor
unit when the oil temperature is too high or too low.
6. Discharge Temperature
The high discharge temperature cutout stops the
compressor unit when the discharge temperature
exceeds the setpoint.
Notice on Using Non-Vilter Oils
CAUTION
Do not mix oils. Failure to comply may result in
damage to equipment.
NOTICE
Vilter does not approve non-Vilter oils for use with
Vilter compressors. Use of oils not specifi ed or
supplied by Vilter will void the compressor warranty.
Due to the need for adequate lubrication, Vilter rec -
ommends only the use of Vilter lubricants, designed
specifically for Vilter compressors. With extensive re
-
search that has been performed, we are able to offer
per each specific application lubricating oils. Use of oil
not specified or supplied by Vilter will void the com
-
pressor warranty.
Please contact your local Vilter representative or the
Home Office for further information.
Operation
All operation (set-point adjustments, calibrations, moni -
toring) of the compressor is done through the micro-
processor. For additional procedural information, refer
to micro-processor manual (35391SC for Vission 20/20
Operating Manual or 35391CM for Compact Logix PLC
Software Manual).
Control System
WARNING
Software programming credentials shall only be
made available by the supplier. The user will only
have access to operational features established by the
supplier. Failure to comply may result in serious injury
or death.
Starting, Stopping and Restarting the
Compressor
Before the screw compressor unit may start, certain condi-
tions must be met. All of the safety setpoints must be in a
normal condition, and the suction pressure must be above
the low suction pressure setpoint to assure that a load is
present. When the “On-Off” switch or “Manual-Auto”
button is pressed, the oil pump will start. When sufficient
oil pressure is built up, the VFD-controlled compressor
motor can start.