Zra Mode Cell Connections - Gamry Interface 1000 Operator's Manual

If your cell is a typical glass laboratory cell, all of the electrodes are isolated from earth ground. In this case, you
may be able to lower noise in your data by connecting the Interface 1000's Floating Ground to an earth
ground.
A binding post on the rear panel of the Interface 1000 is provided for this purpose. A water pipe can be
suitable sources of earth ground.
If any electrode in your cell is at earth ground, you must not connect the Interface 1000
chassis to earth ground. Autoclaves, stress apparatus, and field measurements may
involve earth grounded electrodes.
Make sure that your earth ground connection is made to a legitimate source of earth
ground. Consult a qualified electrician if you are uncertain how to obtain an earth
ground. Connecting the Interface 1000 to an incorrect and unsafe voltage can create a
safety hazard (see Chapter 1 for details).
If you are measuring very small currents, you may find that a metal enclosure completely surrounding your cell
(a Faraday shield) significantly lowers measured current noise. This Faraday shield should usually be connected
to both earth ground and Floating Ground. The Floating ground on the black cell lead is a convenient source
of ground.
If any electrode in your cell is connected to earth ground, you should only connect your Faraday shield to the
black cell lead (Floating Ground).
The alligator clip on any cell connection can be removed to access the underlying banana plug or pin jack. If
you need to permanently change the terminations on your cell cable, feel free to remove the banana plugs and
replace them with your new termination. Resistors in the old termination must be retained. Gamry
Instruments can also provide additional standard or special cell cables.
In either potentiostatic or galvanostatic mode, if you do not have a reference electrode in your cell, the
reference lead can be connected to the counter electrode for a two electrode experiment. The potential reading
will be the difference between the counter electrode and the working electrode.

ZRA Mode Cell Connections

The Interface 1000 can function as a precision Zero Resistance Ammeter (ZRA). It maintains two metal samples
at the same potential and measures the current flow between the samples. It can also measure the potential of
the samples versus a reference electrode.
The cell cable connections for ZRA mode are shown in Table 4-2. Note that the connections are very similar to
those for the potentiostat and galvanostat modes. A second working electrode is substituted for the counter
electrode and the Orange Counter Sense lead must be connected.
Chapter 4 -- Cell Connections--ZRA Mode Cell Connections
Caution
Warning
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