Graco PrecisionMix ii, Инструкция и перечень запасных частей

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10-8
Troubleshooting
Alarm Troubleshooting
Ratio Low or Ratio High
Alarm output will be on Output #1 of Module #2
Ratio alarms occur when the PrecisionMix II 3K has
dispensed a cycle where the amount of resin
compared to the amount of catalyst or the amount of
reducer compared to the amount of catalyst does not
meet the tolerances that have been programmed for
the system.
Ratio Low A:B or C:B
The PrecisionMix II 3K has dispensed a cycle (A:B or
C:B) at a mix ratio less than the ratio target plus the
tolerance.
Ratio High A:B or C:B
The PrecisionMix II 3K has dispensed a cycle (A:B or
C:B) at a mix ratio higher than the ratio target plus the
tolerance.
Common Causes for a Ratio Low or High Alarm
The flow rate is too high
Highly unbalanced pressures from the fluid supply
system or fluid pressure spikes
Slow actuation of the resin, catalyst, or reducer
valves
Checking the Flow Rate
If the alarm occurs while starting up the system after
purging, the flow rate was probably too high.
Restrict the gun needle travel to slow down the initial
fluid delivery rate until the fluid hoses are loaded with
material.
Checking for Unbalanced Pressures
If the alarm occurred after you have been spraying for
some time, the pressures from the fluid supplies could
be unbalanced.
1. Check the catalyst and resin pressures for A:B
ratio alarm, and catalyst and reducer pressures for
C:B alarm.
2. If the pressures are not about equal, adjust both
fluid supply pressures with the fluid regulators,
until the pressures are about the same.
3. If the pressures are already about equal, verify
that the resin, catalyst, and reducer valves are
operating properly.
Checking the Actuation of the Valves
Manually operate the valves by pressing the buttons
on the solenoids. The valves should snap open and
shut quickly.
If the valves move slowly, it could be caused by:
air pressure to the valve actuators is too low,
an interruption in the valve actuating air caused by
dirt or water in the air,
there is something restricting the solenoid or tubing,
the packings on the dispense valves are too tight,
or
a dispense valve knob is turned out too far. The
knob should be turned in until you feel the detents
engaging. You may want to put a piece of tape on
the knobs after they are properly set to discourage
anyone from changing the setting. The recom-
mended setting is three “clicks” open from fully
closed.
Air in the Mixed Material Line
To correct:
change the purge sequence
completely fill the lines with solvent, during last
purge function.