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XTC/3 Operating Manual
A crystal (sensor in the case of Dual Head) switch will automatically occur when:
XTC/3 is configured for a
CrystalTwo
or
Dual Head
sensor type, a film is
START
ed or running and there is another good crystal available when the
active crystal fails.
XTC/3 is configured for a
CrystalSix
or
Crystal12
, a film is
START
ed or
running, and there is at least one good crystal left in the carousel when the
active crystal fails.
XTC/3 is configured for a
Rotary
sensor, the film is
START
ed or running, and
there is at least one remaining good position in the Rotary sensor when the
active crystal fails.
During a crystal switch while in
Deposit
, the thickness will be accumulated at the
setpoint rate. Power will be held constant at the average deposition power during
the prior 6.25 seconds, not counting the last two seconds.
A crystal switch will not automatically occur:
During a state of
STOP
,
READY
, or
IDLE
.
During deposition, if the secondary crystal of a Dual Sensor fails, or the last
good crystal of a Rotary, CrystalSix, or Crystal12 fails, a
TIME-POWER
or
STOP
will occur, depending on whether
TIME-POWER
option
Yes
or
No
is chosen.)
A crystal switch can be manually executed via the front panel
XTSW
key, handheld
controller or remote communications when the system is configured for
CrystalTwo, CrystalSix, Crystal12, Rotary or Dual Head sensors.
NOTE:
The crystal fail message appears when no more good crystals remain.
3.6.8.1 CrystalTwo
In the case of the CrystalTwo (PN 750-212-G2 Dual Sensor with PN 779-220-G1
or PN 779-220-G2 XTAL 2 Switch), the CrystalSwitch output must be wired so that
it simultaneously energizes the:
Solenoid Valve (PN 750-420-G1) which applies the air pressure to actuate the
dual sensor shutter mechanism.
RF relay in the XTAL 2 Switch, exposing crystal #2 while covering crystal #1
and rerouting the RF signal.
This allows the dual sensor to be operated with only one oscillator kit and requires
only one sensor connection at the controller. Power-up initialization is performed
on a dual sensor to verify that the back-up crystal is good. If a crystal fail occurs
while in
Deposit
, the XTC/3 will switch to the backup crystal and continue. If
START
is attempted following completion of the layer and the next layer uses the
same sensor,
START
will not be accepted (unless
Start Without Backup
is set to
Yes
), and the message
No Backup Crystal
appears.