Calibration - Graco VRM Instructions Manual

Calibration

The entire calibration procedure does not always need
to be performed. One of the individual steps can be per-
formed if desired.
1. If Standby or Disabled mode is active, change the
operating mode.
a. Navigate to the Home screen.
b. Press repeatedly to select a different oper-
ating mode then press
2. Navigate to the Calibration screen.
3. Perform Learn Mode.
NOTE: Learn Mode will teach the system the mechani-
cal limits of piston travel. It must be performed whenever
the pump line is rebuilt or if any other maintenance is
performed that may affect the mechanical tolerances in
the pump line. If the machine does not appear to be uti-
lizing the full extent of the pump stroke, or if the machine
appears to be contacting the end of the hydraulic cylin-
der, perform the Learn Mode procedure.
a. From the Calibration screen, press
access the Learn Mode screen.
b. Place waste containers below the ratio check
valves. The next steps will cause the machine to
dispense material.
c. Press then
bottom-most position.
d. After the pump stops moving, press
press . The pump will travel to the top-most
position.
313873C
to accept.
to
. The pump will travel to
then
NOTE: During this process, the system learned the
mechanical limits of piston travel. If the pump did not
reach either piston mechanical travel limit for any rea-
son, repeat the procedure.
4. If at main Calibration screen, press
5. Navigate to the Specific Gravity text box then enter
the A (Red) specific gravity and the B (Blue) specific
gravity.
6. Perform Priming, page 25.
7. Adjust ratio check dispense valve needles.
a. Perform a test dispense at the desired rate and
ratio and note the pressure gauge readings.
b. Perform base purge.
c. Perform Ratio Check dispense, page 30. While
dispensing, adjust the needle valves on the ratio
check valve until pressures match the pressures
observed during the test dispense.
8. Perform Flow Meter Calibration, page 30.
9. Perform 5 dispenses of at least 5 seconds each.
10. Perform Ratio Check, page 30.
11. If ratio is not accurate, go to step 8.
Operation
.
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