Section 4 • Operation; Notice On Using Non-Vilter Oils; Operation; Control System - Emerson VILTER VSS Installation, Operation And Service Manual

Section 4 • Operation

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 recom-
mends only the use of Vilter lubricants, designed spe-
cifically for Vilter compressors. Use of oil not specified or
supplied by Vilter will void the compressor 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 unit is done through the
mi cro-processor. For additional procedural information,
re fer to micro-processor manual (35391SC for Vission
20/20 Operating Manual or 35391CM for Compact
Logix PLC Software Manual).
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.
VSS/VSR/VSM/VSH/VSSH Compressor • Installation, Operation and Service Manual • Emerson • 35391S

Control System

Starting, Stopping and Restarting The
Compressor
For additional control information, refer to micro-proces-
sor manual ( 35391SC for Vission20/20 Operating Manual
or 35391CM for Compact Logix PLC Software Manual).
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
Before the screw compressor unit can start, certain con-
ditions 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 ensure a
load is present. When the "ON/OFF" switch or "Manual-
Auto" button is pressed, the oil pump will start. When
sufficient oil pressure has built up and the compressor
capacity control and volume ratio slide valves are at or
below 10%, the compressor unit will start.
The amount of oil pressure that needs to be achieved
before compressor start is at least 6 psig above the
discharge pressure. For additional information on
Low Oil Pressure at Start, see Troubleshooting Guide -
General Problems and Solutions in Section 6.
If the compressor is in the automatic mode, it will now
load and unload and vary the volume ratio in response
to the system demands.
Stopping/Restarting
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 set-
point. If any of these conditions turns the compressor
unit off, the slide valve motors will immediately energize
to drive the slide valves back to 5% limit. The control
motors will be de-energized when the respective slide
valve moves back below 5%. If there is a power failure,
the compressor unit will stop. If the manual start on
power failure option is selected, restarting from this
condition is accomplished by pushing the reset button
to ensure positive operator control. If the auto start on
power failure option is selected, the compressor unit
will start up after a waiting period. With both options,
NOTE
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