Advanced Measurement Technology 273A, User Manual

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Model 273A Potentiostat/Galvanostat User’s Manual
10. AC E OUTPUT (used only in units equipped with the 273A/92 Electrochemical Impedance
Interface option): Outputs the ac voltage signal from the test cell. The signal is controlled by
commands from an external computer via the GPIB or RS-232C port.
11. MULTIPLEXED OUTPUT (used only in units equipped with the 273A/92 Electrochemical
Impedance Interface option): Either a current or voltage signal can be output from this
connector as determined by commands from an external computer via the GPIB or RS-232C
port. Note: This output is intended for use with Princeton Applied Research electrochemical
impedance systems.
12. AC INPUT (used only in units equipped with the 273A/92 Electrochemical Impedance
Interface option): This connector accepts a sine wave input from an external oscillator, such
as that supplied by a Princeton Applied Research lock-in amplifier. The nominal frequency
range is 50 µHz to 100 kHz, although this is dependent on loading. Input voltage must be no
greater than 5 volts rms. This signal can be used to modulate the signal sent by the Model
273A to the cell, and can be attenuated as desired. It is controlled by commands from an
external computer via the GPIB or RS-232C port.
3.1.15. 273A/92 Electrochemical Impedance Interface Option
The 273A/92 Electrochemical Impedance Interface option (previously called the AC Interface
option) is intended primarily for use with Princeton Applied Research electrochemical
impedance systems, but can also be used for ac voltammetry applications. This option is
designed to allow superposition of an externally generated ac excitation signal on the dc signal
generated by the Model 273A. The Model 273A Remote Programming Command Handbook
describes the computer commands used with the Model 273A/92 option. Section 3.2.10 of this
chapter describes how it works.
3.1.16. Accessories
1. MODEL 407A INTERFACE: This accessory allows the Model 273A to be used in conjunction
with the Model 303A Static Mercury Drop Electrode. This adapter requires two cables to
make the necessary connections. One cable connects to the Model 273A AUXILIARY
INTERFACE connector and the other to the Model 303A INPUT connector. The Model 407A
re24 V at 1 A. A suitable power supply is included with it.
2. MODELS RE0150 and RE0151 RECORDERS: These recorders are well suited to use with
the Model 273A and a custom cable is available to simplify the necessary interconnections.
Both recorders use 11 x 17 inch paper. The principal difference between them is that the
RE0151 incorporates a time base.
3. In addition, a variety of cells, electrodes, and other items are available as described in the
Princeton Applied Research Electrochemical Accessories Catalog.
3.1.17. Polarity Convention
The Model 273A follows the American polarity convention and the display indications are
consistent with that convention. Positive current is cathodic, that is, a current is defined as
positive if reduction is taking place. Negative current is anodic, that is, a current is defined as
negative if oxidation is taking place. A full description of the polarity convention used is given in
1.1.4.
3.1.18. Metric Hardware
Equipment manufactured by Princeton Applied Research uses American Standard and metric
fasteners and related hardware. For this reason an electronic technician servicing or aligning the
apparatus should make a special effort to keep track of any hardware removed from the chassis,
the cable connectors, and attached equipment.