Laurell Technologies
Operations Manual WS-400 Lite Series
All information contained in this manual is the property of Laurell Technologies Corporation® and is NOT to be edited, reproduced or
distributed without express written permission from a corporate officer.
33
3.2.2 VACUUM INTERLOCK
Two conditions must be met to allow operation of systems equipped with a vacuum hold
down type chuck.
The first condition that must be present is a vacuum source with vacuum ≥15”Hg.
A factory preset sensor will not allow the system to operate with vacuum <15”Hg. This
interlock insures that adequate vacuum is applied to the substrate. Inadequate vacuum
will cause an unsafe condition and may cause a substrate to spin off the chuck and
cause breakage. A
flashing
value (measured in inches of Hg) of the vacuum applied to
the substrate is an indication that this requirement has not been met. Without proper
vacuum, a process cannot be started. If the vacuum falls below the required level while
a process is running, the program will be halted at that point and an E04 error message
will appear on the LCD display
1
. Once vacuum has been re-established it is necessary
to press the
RUN/STOP
key on the keypad to re-start the program from where it
stopped.
The second required condition, which MUST be present for the air operated
vacuum valve to function, is sufficient seal purge pressure.
Since the vacuum
valve is pneumatic it must have enough N
2
/ CDA to operate. See section 3.2.3. If there
is insufficient N
2
/CDA pressure the controller will
flash
“
CDA
” and
“VACUUM”
indicating no CDA or vacuum. (See Figure 3-3 for an illustration of this condition.) If
there is ≤ 60psi of CDA the vacuum screen may show that there is vacuum ≥ 15”Hg but
the lack of N
2
/ CDA will
flash
“
CDA
” and cause an E10 error.
WITHOUT THE
PROPER N
2
/CDA PRESSURE THE SYSTEM WILL NOT OPERATE.
Press the VACUUM button on the keypad to turn on/off the vacuum valve. Once
actuated, the vacuum valve
cannot be turned off until the motor is stopped @ 0 RPM for
1 second. This safety feature insures that vacuum cannot be inadvertently turned off
until the chuck comes to a complete stop.
Figure 3-3
FLASHING VACUUM DISPLAY
1
See Section 4.1 - Errors
Flashing Vacuum
