Graco PrecisionFlo XL Instructions Manual page 106

Theory of Operation
Volume On Data Output
The data outputs represent binary values. To calculate volume, add the volumes together.
Example 1:
Output ON:
State
Total Volume = 1 + 2 + 8 + 64 + 2048 = 2123 cc
Example 2:
Output ON:
State
Total Volume = 1 + 16 + 32 = 49 cc
Typical Volume Reporting Procedure
1. Robotic controller sets DISPENSE to LOW and
DISPENSE DONE DELAY expires or a JOB
COMPLETE signal from the robot ends a dispense
job.
2. The PrecisionFlo XL control stops measuring
volume dispensed. An entry is made to the data
log which records the volume dispensed. On
installations with two flow meters, this is the com-
bined volume of both flow meters.
3. Robot controller sets the VOLUME REQUEST
signal HIGH.
4. PrecisionFlo XL control places the 16 bits of
volume information on the data bus.
5. PrecisionFlo XL control sets the VOLUME ON
DATA signal HIGH.
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Output OFF:
Output OFF:
6. Robotic controller reads the data.
7. Robotic controller sets the VOLUME REQUEST
signal LOW to indicate volume data has been
read.
8. PrecisionFlo XL control sets the VOLUME ON
DATA signal to LOW.
9. After volume is reported, if a fault was detected
during the cycle, the PrecisionFlo XL control
places the fault code on the data bus. (See Fault
Reporting on page 103.)
10. When the robot sets the DISPENSE line high to
begin the next cycle, the PrecisionFlo XL control
discards previously stored volume data.