Height Sensor; Laser Height Sensor; Table 8-6 Height Sensor Troubleshooting; Table 8-7 Laser Height Sensor Troubleshooting - Nordson Asymtek Spectrum Series Installation, Operation & Maintenance Manual

8.4.6

Height Sensor

Symptom
Probe does not drop or
retract
Probe either drops too
slowly or slams down with
too much force
Needle hits substrate
Probe hits substrate
before it is fully extended
8.4.7

Laser Height Sensor

Symptom
Height Sensor does not
power up
Height Sensor does not
trigger
Intermittent function
Troubleshooting

Table 8-6 Height Sensor Troubleshooting

Possible Cause
Probe is damaged
No air pressure
Flow control improperly set
(closed to off) or there is a
pinched pneumatic line for the
height sensor.
Main air pressure not set
properly
Flow control improperly set
Probe tip is lower than the
needle tip when valve is in
dispensing position.
The Height Sensor is not set up
properly.
HS velocity is set too high
Safe Z-height too low
Retract distance too low

Table 8-7 Laser Height Sensor Troubleshooting

Possible Cause
Height sensor is not plugged in
Bad resistor on the main board
d-sub connection.
Dip switches not set properly
Height sensor lens is dirty
No communication with PC
Loose or frayed cables
Recovery
Check for bent probe. Replace if necessary. See
Replacing the Height Sensor
Verify main air pressure is ON (I).
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.
Readjust main air pressure regulator to system's
nominal pressure.
Readjust the flow control located in the servo shelf.
Refer to the system pneumatic diagram.
Adjust probe and perform "Valve Offsets" in FmXP.
See 5.10 Adjusting the Height Sensor
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.
Reduce the HS velocity to 2 inches per second and re-
run the valve offsets. Test the HS from the diagnostics
menu if necessary.
Reteach Safe Z-height. See
Reteach the retract distance in the height sensor setup.
Refer to the FmXP User Guide or Online Help.
Recovery
Check power connection and verify that Height Sensor
plugged in.
Use a multimeter to verify that the main board d-sub
resistor is good.
Verify that dip switch number 6 on SW1 on the Main
Board is set to on. See Figure 8-2.
Check and clean the Height Sensor lens.
Verify I/O tools can toggle height sensor bits.
Check cables for tight connection and wear.
9.9
Probe.
Probe.
6.6.2 Safe Z-height.
8-7