Advanced Measurement Technology 273A, User Manual

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Model 273A Potentiostat/Galvanostat User’s Manual
Note: The dummy cell resistor has a 1% tolerance rating. As a result, the current indications
can be at least 1% off with respect to the values indicated in this procedure. Note also
that residual drift or noise in the Model 273A itself can contribute a small additional
Plug the Model 273A into a suitable source of ac power. (See Chapter 2 for line voltage selection
and safety information.)
9. Set the 273A's POWER ON/OFF switch to ON.
10. Reinitialize the system by pressing the following sequence of keys:
[FUNCTION] [1] (0] [YES] [ENTER]
4.4. Procedure
The following steps program the Model 273A to do a controlled-potential experiment on the
100k
dummy cell resistor located in the electrometer housing. A scan starting at 0 V, advancing
to 1 V, and then returning to 0 V will be applied. The current in the resistor will track this voltage,
starting at zero, increasing to 10 µA, and then decreasing to zero again. A voltage corresponding
to this current will appear at both the I MONITOR connector and at the OUTPUT connector. With
a selected current range of 10 µA, the voltage at these connectors will start at 0 V, increase to 1
V, tracking the scan, and then return to 0 V. The current in the resistor will be displayed
throughout the experiment.
1. Note the Model 273A display. There are two information lines. The measured cell current
and potential are displayed on the upper line. The lower line displays various messages.
2. Press the [POTENTIOSTAT] key. The associated indicator should light, indicating that the
273A is in the controlled-potential mode.
3. Pres [E/I 1]. The display message line will indicate that the E/I 1 is to be entered. Then key.
[0] [ENTER]
entering 0 V as the programmed starting potential for the scan to be performed.
4. Press [DELAY 1]. The display message line will indicate that DELAY 1 is to be entered. After
that, key.
[1] [0] [SEC] [ENTER]
entering 10 s as the time for which E/I 1 (0 V) will be applied before beginning the scan.
Note the message at the end of the lower display line. It should indicate that the delay will be
performed with the cell off. If it indicates the CELL ON state, press the Scan Setup CELL OFF
key to establish the desired CELL-OFF delay.
5. Press [SCAN 1]. The display message line will indicate that SCAN 1 is to be entered. Next
key.
[2] [0] [ENTER]
entering 20 mV/s as the programmed scan rate for the first leg of the scan.
6. Press [E/I 2]. Then key: