Nordson Asymtek Spectrum S-920, Installation, Operation & Maintenance Manual

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Troubleshooting 8-7
8.4.6 Height Sensor
Table 8-6 Height Sensor Troubleshooting
Symptom Possible Cause Recovery
Probe is damaged
Check for bent probe. Replace if necessary. See 9.9
Replacing the Height Sensor Probe .
No air pressure Verify main air pressure is ON (I) .
Probe does not drop or
retract
Flow control improperly set
(closed to off) or there is a
pinched pneumatic line for the
height sensor.
Readjust the flow control located in the servo shelf by
opening it to ¾ open. Refer to the system pneumatic
diagram. Verify there is no kinked or pinched line from
the height sensor solenoid, through the cat track and to
the height sensor.
Main air pressure not set
properly Readjust main air pressure regulator to system’s
nominal pressure.
Probe either drops too
slowly or slams down with
too much force
Flow control improperly set
Readjust the flow control located in the servo shelf.
Refer to the system pneumatic diagram.
Probe tip is lower than the
needle tip when valve is in
dispensing position.
Adjust probe and perform “Valve Offsets” in FmXP.
See
5.10 Adjusting the Height Sensor Probe .
The Height Sensor is not set up
properly.
Test the height sensor. FmXP provides a height sensor
test utility from the tools, diagnostics menu. The probe
can be toggled up and down to verify probe
functionality. There is also a test procedure that
captures HS trigger values. FmXP can display a
statistical analysis of the captured values.
Needle hits substrate
HS velocity is set too high
Reduce the HS velocity to 2 inches per second and re-
run the valve offsets. Test the HS from the diagnostics
menu if necessary.
Safe Z-height too low Reteach Safe Z-height. See 6.6.2 Safe Z-height .
Probe hits substrate
before it is fully extended
Retract distance too low
Reteach the retract distance in the height sensor setup.
Refer to the
FmXP User Guide or Online Help.
8.4.7 Laser Height Sensor
Table 8-7 Laser Height Sensor Troubleshooting
Symptom Possible Cause Recovery
Height sensor is not plugged in
Check power connection and verify that Height Sensor
plugged in.
Height Sensor does not
power up
Bad resistor on the main board
d-sub connection. Use a multimeter to verify that the main board d-sub
resistor is good.
Dip switches not set properly
Verify that dip switch number 6 on SW1 on the Main
Board is set to on. See Figure 8-2.
Height sensor lens is dirty Check and clean the Height Sensor lens.
Height Sensor does not
trigger
No communication with PC Verify I/O tools can toggle height sensor bits.
Intermittent function Loose or frayed cables Check cables for tight connection and wear.