EFD Ultra 325TT User Manual page 64

®
A NORDSON COMPANY
Symptom
Probe does not drop
or retract
Needle hits Substrate
Dispenses at wrong
Z-axis position
PDA indicates an error
message (ERR 65 –
Height Sensor has
detected surface before
starting)
Probe hits Substrate
when setting Tip-to-
Probe Offset
To Replace Height Sensor Probe
To remove the sensor you will need to remove the Z plate. To do this, pull it down by hand to
access the Z balance spring or springs. Tie a wire to the spring then unhook it. Remove the four
bolts from the Z head. You can now place it in top of the X beam to work on the probe. You
should be able to straighten it without removing it. If you have to remove it, take the two Phillips
screws out from the front of the Z plate. Remember where the little spring goes. When
reassembling, be careful when you tighten the probe screw. Too tight and you can bend the
probe. Reassemble in reverse order.
Table 11.3: Height Sensor Troubleshooting
Possible Cause
1. Probe malfunction.
2. No air pressure.
Probe tip is lower than needle tip
when valve is in dispensing position.
1. Height Sensor has been adjusted,
loose or binding in the drive
system.
2. Nozzle/needle has been changed
without resetting Tip-to-Probe
Offset
1. Height Sensor was tripped before
Z-axis started the height sense
move. Either the probe is still
retracted, stuck in the up position
or adjusted incorrectly.
2. Low air pressure.
3. Electrical wires are not plugged
in properly at the Z-head.
1. Safe Z may be set too low.
2. Probe is not hitting sensor.
Ultra TT User's Guide
Recovery Procedures
Check for bent probe.
Verify Main Air Pressure is ON and
set to 70 psi.
Perform Tip-to-Valve-Offset. Refer
to section 4.1.1.
Perform a Tip-to-Probe Offset.
Refer to section 4.1.1.
Correct the Height Sensor alignment
and rerun.
Verify Main Main Air Pressure is ON
and set to 70 psi.
Check the connection at the top of
the Z-head.
Raise Safe Z.
Check to make sure that the probe
is not too far below tip when
extended (minimum distance below
tip is 6 mm).
Version 1.2
64