Air Flow Switch (Afs) Function - Graco ProMix 2KS Operation Manuals

System Operation

Air Flow Switch (AFS) Function

Air or Air-assisted Guns
The air flow switch (AFS) detects air flow to the gun and
signals the ProMix controller when the gun is triggered.
The AFS functions with the flow meters to ensure that
system components are functioning correctly.
For example, if a flow meter fails or clogs, pure resin or
catalyst could spray indefinitely if the ProMix does not
detect the condition and intervene, which is why the
AFS is so important.
If the ProMix detects through the AFS signal that the
gun is triggered, yet there is no fluid flow through the
meter, a Dose Time Alarm (E-7 or E-8) occurs after 40
seconds and the system shuts down.
F . 60: Air Flow Switches
IG
54
Operating Without Air Flow Switch
It is not recommended to run without an air flow switch.
If a switch fails, replace it as soon as possible.
Airless Gun
It is not recommended to use an airless gun with the
ProMix 2KS. Two issues can arise from operating with-
out an air flow switch:
•
•
System Idle Warning (E-15)
This warning occurs if the ProMix is set to Mix
AFS
and 2 minutes have elapsed since the system received
a flow meter pulse.
TI13350a
In applications using the AFS, triggering the gun clears
the warning and you can start spraying again.
Without the AFS, triggering the gun does not clear the
alarm. To start spraying again, you must press Standby
Without a gun trigger/air flow switch input the Pro-
Mix 2KS does not know it is spraying and will not
generate a Dose Time Alarm (E-7 or E-8). This
means there is no way to detect a failed meter. You
could spray pure resin or catalyst for 2 minutes with-
out knowing.
Since the ProMix 2KS does not know it is spraying
because there is no gun trigger/air flow switch input,
it will go into System Idle (E-15) every 2 minutes
when in Mix mode.
, then Mix , then trigger the gun.
,
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