Service manual

19 – 5
Vission 20/20 • Operation and Service Manual •Vilter/Emerson • 35391SC 1.9
Section 19 • Configuration
selection is critical for proper volume slide control.
Model:
• Drop-down box to select the compressor size. This
selection is critical for proper volume slide control.
Refrigerant:
• Drop-down box to select the type of refrigerant. This
selection is critical for proper volume slide control.
Other (K-Factor):
• Optional setting to adjust volume slide control.
Compressor Control
Vilter compressors typically run in one of two control
modes, suction pressure or process temperature con-
trol, see Figure 19-2. Confi guration Screen - Page 2.
Suction Pressure Control:
• This defi nes the suction pressure input as the pro-
cess variable and all controls will be based on suction
pressure. The operator has the option to select up to
two controllers where each can have its own set of
setpoints.
Process Temp. Control:
• This defi nes the process temperature input as the
process variable and all controls will be based on the
process temperature. The operator has the option to
select up to two controllers where each can have its
own set of setpoints.
Optional Function Selection
The following options are additional features of the
Vission 20/20 that can be selected. Some of these op-
tions will not be available for selection unless the proper
I/O cards are installed and enabled, see Figure 19-2.
Confi guration Screen - Page 2.
Compressor VFD:
• Enables the compressor motor VFD option.
% Slide Volume Position:
• Unused.
Economizer Pressure:
• Enables the economizer pressure input.
Superheat Monitor:
• Enables the superheat safety algorithms.
Condenser Control
The values in this section enables the condenser con-
trol feature of the Vission 20/20. Once selected the
checkboxes will become available for selection and the
condenser control screen will be available via the menu
screen. Some of the options check boxes in this section
may not be available for selection unless the proper
I/O cards are installed and enabled, see Figure 19-2.
Confi guration Screen - Page 2.
Ambient Sensor:
• Enables the ambient temperature option for the con-
denser control algorithm.
Wetbulb Sensor:
• Enables the wetbulb temperature override option for
the condenser control algorithm.
VFD Fan:
• Enables the VFD output option for the condenser
control algorithm.
Oil Pump
This section defi nes how the Vission 20/20 will control
the oil pump, see Figure 19-2. Confi guration Screen -
Page 2.
No Pump:
• Disables all functions for oil pump control.
Cycling:
• Enables option for cycling oil pump. Oil pump is cy-
cled on and off depending on compressor differential
pressure.
Full Time:
• Enables option for full time oil pump. Oil pump will
always be running while the compressor is running.
# Pumps:
• Not currently used
Oil Flow Control:
• Enables option for oil fl ow control. Oil fl ow control
will vary analog output for controlling danfoss valve
opening % depending on capacity slide position. Oil
fl ow control output will be regulated only when com-
pressor is running, start condition is over i.e. low oil
pressure timer is elapsed, pumpdown control opera-
tion is not running and oil injection temperature is
above oil injection temperature override setpoint. If
any of the above condition is not satisfi ed, then oil
fl ow analog output will be 4 mA which corresponds