efd 741md-ss 사용자 가이드
Troubleshooting Guide
No fluid flow
•
If valve operating air pressure is too low,
the valve will not open. Increase air
pressure to 70 psi (4.8 bar) minimum.
the valve will not open. Increase air
pressure to 70 psi (4.8 bar) minimum.
•
The reservoir air pressure may not be
high enough. Increase pressure.
high enough. Increase pressure.
•
The needle stroke adjustment may be
closed. Open stroke adjustment.
closed. Open stroke adjustment.
•
Material may have clogged the fluid
body or output tip adapter. Clean the
valve.
body or output tip adapter. Clean the
valve.
•
Dispensing tip retaining nut may not
have been tightened enough to unseat
the needle. Tighten the nut.
have been tightened enough to unseat
the needle. Tighten the nut.
Steady drip
•
Remove the tip adapter/seat assem-
bly. Clean and inspect the needle.
Replace dispensing tip.
bly. Clean and inspect the needle.
Replace dispensing tip.
•
Make sure tip size is not larger than
22 gauge.
22 gauge.
Fluid leaks out the drain hole
•
Fluid leaking out the drain hole on the
side of the valve indicates the needle
packings are worn. Replace needle
packings.
side of the valve indicates the needle
packings are worn. Replace needle
packings.
Inconsistent deposits
•
Inconsistent deposits can result if the air
pressure controlling the valve and/or
supplying the reservoir is fluctuating or if
the valve operating pressure is less than
70 psi (4.8 bar). Check to be sure air
pressures are constant and the valve
operating pressure is 70 psi (4.8 bar).
pressure controlling the valve and/or
supplying the reservoir is fluctuating or if
the valve operating pressure is less than
70 psi (4.8 bar). Check to be sure air
pressures are constant and the valve
operating pressure is 70 psi (4.8 bar).
•
The time the valve is open must be con-
stant. Check to be sure the valve con-
troller is providing a consistent output.
stant. Check to be sure the valve con-
troller is providing a consistent output.
Calibration Feature
The stroke control reference ring of each
741MD-SS valve is factory calibrated to
zero position. Slight internal variations in
dispensing tips may require the stroke
control to be recalibrated when tips are
changed. To do so:
741MD-SS valve is factory calibrated to
zero position. Slight internal variations in
dispensing tips may require the stroke
control to be recalibrated when tips are
changed. To do so:
1. Make a note of the current stroke
setting number.
2. Turn the calibration knob (inner)
counterclockwise one full turn.
3. Install the new dispensing tip and
ensure that the retaining nut is tight-
ened fully.
ened fully.
4. Turn the stroke adjustment knob
(outer) clockwise until it stops at the
zero position.
zero position.
5. Turn the calibration knob clockwise
until it stops. The stroke adjustment
is now calibrated to zero.
is now calibrated to zero.
6. Reset stroke to the required position
noted in step 1.
In the event that the stroke reference ring
must be repositioned or reset to the zero
mark, use the following procedure:
must be repositioned or reset to the zero
mark, use the following procedure:
A. Remove the dispensing tip, if installed.
B. Turn the small knob counterclock-
wise one full turn.
C. Turn the large knob clockwise until it
stops.
If the zero on the reference ring does not
line-up with the index mark, continue with
the following steps:
line-up with the index mark, continue with
the following steps:
D. Loosen the small set-screw located
on the reference ring.
E. Rotate reference ring until it aligns
with the reference line on the air
cylinder body.
cylinder body.
F.
Tighten the small set-screw to lock
the reference ring into position.
the reference ring into position.
G. Install a dispensing tip and follow
calibration procedure steps 3 to 5.
A NORDSON COMPANY
USA: 800-556-3484 or +1-401-434-1680
Europe: 0800 585733 or +44 (0) 1582 666334
Asia: +86 (21) 5854 2345
technical@efd-inc.com
Europe: 0800 585733 or +44 (0) 1582 666334
Asia: +86 (21) 5854 2345
technical@efd-inc.com
www.efd-inc.com
©2006 Nordson Corporation 741
MD-MAINT-01 v062606