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XTC/3 Operating Manual
The
Crystal Fail
state can be cleared by pressing
TOGL
in the
Sensors
screen
with the cursor on
Clear Failed Crystals
or by powering down and up again. In
both cases, XTC/3 will run the next layer using the last crystal position it switched
to.
Crystal Fail
can also be cleared by executing a crystal switch from the front
panel with the
XTSW
key, by pressing
TOGL
in the
Sensors
screen with the cursor
on
Switch Crystal
or via communications commands R14 (Crystal Switch) or R26
(Clear All Crystals). A good crystal must be available to switch to in the case of
using the crystal switch method.
3.6.8.2 CrystalSix
On power-up, all crystals are read to determine how many good and bad crystals
are present. XTC/3 uniquely identifies and tracks all six positions in the CrystalSix.
During deposition, XTC/3 will automatically switch to the next position with a good
crystal when there is a crystal failure. When the last good crystal fails, XTC/3 will
go directly to
Time Power
or
STOP
, as appropriate.
When the sensor selected is a CrystalSix, the relay contacts are pulsed closed for
one second, opened for one second, closed for one second, then opened for each
position. The first one second closure will advance the CrystalSix carousel into an
intermediate position between two crystals. Opening the closure for one second
allows the ratchet mechanism to relax whereupon the second contact closure
advances the next crystal into the proper position.
3.6.8.3 Crystal12
When first turn on, XTC/3 will rotate the sensor until position one is detected. Then
XTC/3 will continue to rotate through the other eleven positions to determine the
state of all crystals. At the conclusion of the sequence, the
Sensor
screen shows
the sensor in position one and the position number of any failed crystals.
XTC/3 verifies that the resistance value is correct at each position. If the value is
not as expected, XTC/3 pulses again and rechecks the position. If position one is
not detected, or after twelve pulses of the wrong value, XTC/3 reports a
Crystal
Sw Fail
message. In that case, all crystals are also marked as failed.
When the carousel is removed from the sensor for crystal replacements, XTC/3
displays
Carousel Open
. This message also appears if there is no connection
between the XIU (oscillator) and the sensor.
After the carousel is replaced, XTC/3 assumes the current position is twelve and
all crystals are failed. A
Crystal Switch
or
Rotate Head
function must be initiated
in the
Sensor
screen or via Remote Communication to enable XTC/3 to catalog
the state of all crystals and to return to position one. This must also be done after
the sensor type has been changed to
Crystal12
. The
Rotate Head
function is
permitted only in
Ready
or
Idle
at the end of a process.