Advanced Measurement Technology 273A, Руководство пользователя

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Model 273A Potentiostat/Galvanostat User’s Manual
5.2.6. CONTROL Group
1. SCANNING: This indicator is off at power-up and on during each active scan. At powerup,
the E/I APPLIED indicator is lighted, indicating that the 273A is ready to apply the previously
speed E/I APPLIED level. (It won't actually be applied, however, unless both the CELL
switch and the CELL ENABLE switch are ON.) If a scan is initiated by pressing START, the
E/I APPLIED indicator goes out and the SCANNING indicator lights, signifying that a scan is
underway. The progress of the scan can be monitored by observing the Scan Status Display.
When the scan ends, either by pressing STOP or by completing the programmed sequence,
the SCANNING indicator will go out. One of the three Scan Status Display Indicators, E/I 1,
E/I 2, or E/I 3, will remain lighted. An Override (see Section 5.2.4) determines whether the
cell will be ON or OFF.
2. HOLDING: This indicator lights if the HOLD/CONTINUE key has been pressed during a
scan. Pressing the HOLD/CONTINUE key causes the scan to halt until the key is pressed
again (CONTINUE), at which point it resumes and the HOLDING indicator extinguishes.
If a HOLD occurs when a potential/current is applied, it will continue to be applied, subject to
the usual Cell switch and Cell Enable switch constraints. This is true if the hold takes place at
any time during the scan sequence (E/I 1, DELAY 1, SCAN 1, E/I 2, DELAY 2, SCAN 2, E/I
3). If the hold occurs during a delay measured in seconds, time is not counted for the
duration of the hold. If it occurs during a delay measured in drift, the drift rate is not
measured during the hold. If applied during SCAN 1 or SCAN 2, the scan simply halts and
the potential/current in effect as of the moment of the halt continues to be applied.
3. [START]: This key is used to start a scan. When it is pressed, E/I 1 lights and the scan
progresses as programmed.
4. [HOLD/CONTINUE]: This key is used to start a hold interval as described in the discussion
of the HOLDING indicator. Pressing the key a second time continues the measurement
sequence.
5. [ADVANCE]: This key's function differs according to whether a scan sequence is in progress
when it is pressed.
If pressed during a scan, it causes the sequence to immediately advance to the next step.
For example, if pressed during the DELAY 1 interval, the sequence would immediately
advance to SCAN 1. Similarly, in half-cycle or single-cycle scanning, if the next step would
advance the sequence to the end of the scan, the scan would halt.
If pressed at any other time, the message "NOT SCANNING" is displayed.
6. [STOP]: This key stops a scan sequence, immediately establishing the end-of-scan
condition, and E/I 1 on the Scan Status Display lights. The applicable Override (see Section
5.2.4) determines whether the cell will be ON or OFF.
7. CYCLE CONTROL: The Cycle Control key allows selection of three different cycle modes:
HALF CYCLE, SINGLE CYCLE, and CONTINUOUS. A separate indicator is provided for
each and one of the three will always be lighted. Selection is accomplished with the
associated key. Each time the key is pressed, the selection increments, the sequence being
HALF CYCLE to SINGLE CYCLE to CONTINUOUS and from there back to HALF CYCLE. A
brief description of each follows.
a. HALF CYCLE: This is the simplest cycle, involving only two potential/current settings. A
half-cycle sequence proceeds as follows.
i. DELAY 1 at E/I 1.