X-Cite Exacte, Руководство пользователя

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22
X-Cite
®
exacte User Guide
035-00283 rev 3
6.7.3 Use the UP and DOWN buttons to step through the intensity settings. Size (and
unit) of the step depends on whether the unit is operating in relative or absolute
mode.
Step Size in
RELATIVE Mode
Step Size in
ABSOLUTE Mode
COARSE 10%
Value in watts corresponding
to 10%
FINE
1% 0.01 W
6.8 Viewing Accumulated Lamp Hours
6.8.1 The X-Cite
®
exacte system automatically accumulates the number of hours for
which the lamp has been on, and shows this information on the LED display. The
lamp hours are shown when the unit is in Lamp Hour mode.
6.8.2 To put the X-Cite
®
exacte in Lamp Hour Mode, press the MODE button until the
HRS LED on the front panel is illuminated. The LED display will show four digits
with a flashing decimal point at the end (“
XXXX.
”). The number shown here will
be the total number of hours the lamp has been in operation.
6.9 Closed-Loop Feedback
™ (CLF)
6.9.1 The X-Cite
®
exacte is equipped with Closed-Loop Feedback
™ (CLF) control to
ensure that from the beginning to the end of an experiment, the illumination level
remains constant. When CLF is enabled, the system will automatically
compensate for any fluctuation or degradation in light intensity by adjusting the
iris position. For best results, allow the lamp to warm up and stabilize to its
normal operating temperature, about 30 minutes.
6.9.2 To enable CLF: Set the intensity to the desired level. Press and hold the MODE
button, then press and release the UP button. The CLF light will turn on. (Note:
UP must be released before MODE
—
treat MODE
like a “shift” key).
6.9.3 To disable CLF: Press and hold the MODE button, then press and release the
UP button. The CLF light will turn off.
6.9.4 Even over several days, the output power will be maintained within ±2% of the
set point. (Set point = the output level at which CLF is enabled.) For verification
of the actual output power, the variance from setpoint can be logged over time
and exported as a data file (see
section 9 for additional information).
Important Notes about CLF
Since CLF uses the iris to make adjustments to output power, CLF cannot be
used if iris position is 100% open. Similarly, if the initial set point is 95%, and
over a continuous multi-day experiment the iris needs to be opened to 100% to