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Operation Modes
96
309738L
Operation Modes
Dispense Modes:
Manual Mode
When in Manual mode, the PrecisionFlo LT control
reacts only to input from the user interface. The Preci-
sionFlo LT control ignores automation controller signals
when in Manual mode.
Automatic Mode
When in Automatic mode, the PrecisionFlo LT control
remains in a ready state, indicated by the DISPENSER
READY signal, and reacts to inputs such as DISPENSE
and VOLUME REQUEST signals from the automation
unit.
When a fault is detected, the PrecisionFlo LT control
sets the FAULT present signal HIGH, and may set the
DISPENSER READY signal LOW. Fault detection can
also occur during manual dispensing.
During dispensing, the PrecisionFlo LT control performs
a variety of functions in the background. These func-
tions include fault monitoring, real-time volume com-
pensation, measuring volume (per job), and continuous
calculations to maintain the pressure and flow control
loops.
Control Modes:
Volume Monitor
The automation I/O or Manual dispense command and
the 100% pressure setting are used to set a pressure
target. The regulator adjusts to maintain this pressure.
In automatic mode the controller compares the dis-
pensed volume to the target volume and sets volume
faults if needed.
Bead Control
The automation I/O command for manual dispense
establishes a Flow Rate target. A pressure setpoint is
determined from the calibration results and the volume
compensation values. The regulator adjusts to maintain
the pressure setpoint, volume compensation will adjust
the pressure setpoint to achieve the desired flow rate.
Batch Dispense:
The automation I/O command and the 100% pressure
settings are used to set the pressure target. The regula-
tor adjusts to maintain this pressure. In automatic mode
the dispense valve is closed when the target volume is
reached, a job complete signal is received by the con-
trol, or the job timer expires.
Pressure Control
The automation I/O or manual dispense command and
the 100% pressure setting are used to set a pressure
target. The regulator adjusts to maintain this pressure.
Automation I/O Modes:
Analog
0-10 VDC signal from the automation unit is used to
determine the pressure or flow command. A 10 volt
command will establish a pressure or flow rate com-
mand equal to the 100% value entered during the cali-
bration procedure. If an analog signal < 1vdc is given
the pressure or flow command is determined by the
value entered in the default/fixed command parameter.
Fixed
The default/fixed value entered in the setup is used to
determine the pressure or flow command.