Gamry ECM8, Operator'S Manual

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Chapter 2 -- Introduction--Keyword Definitions
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Keyword Definitions
The following key terms will be used throughout this manual.
Active Cell
The active cell is the cell (if any), which is currently connected to the system potentiostat. Any
electrochemical measurements are made on the active cell.
Aux A/D
The term Aux A/D is used to describe an optional switch in each ECM8 channel. This switch
allows connection of two BNC connector contacts associated with that channel to a common BNC
connector. The term Aux A/D is used for this switch because the original use for this switching
system is multiplexing a signal from each channel to the single Auxiliary A/D input often found on
potentiostats.
The connectors and relays used for the Aux A/D function are no longer included in the standard
ECM8. They can be ordered as a factory installable option.
The Aux A/D switches are not restricted to use as an Auxiliary A/D multiplexer. It can also be used
as a demultiplexer or for other switching applications.
Cell
The term cell is used to describe either an electrochemical cell or the switches needed to connect
an electrochemical cell to the system potentiostat.
Channel
An ECM8 contains eight channels. A channel includes cell switching, an Aux A/D switch (optional),
a local potentiostat and a D/A converter. The term cell will be used when only the cell-switching
portion of a channel is being discussed.
Inactive Cell
The term inactive cell refers to any cell not currently connected to the system potentiostat.
Inactive is a slightly misleading term, since an inactive cell can actually be potentiostated by the
ECM8's local potentiostat on that channel.
Inactive Mode
Inactive cells can be open, connected to a local potentiostat, or shorted. The term inactive mode
is used to describe this choice of control mode for inactive cells.
Local Potentiostat
A simple low current potentiostat used to maintain potential control on inactive cells. Unlike the
system potentiostat, the local potentiostat is incapable of making electrochemical measurements.
System Computer
The computer responsible for coordinating operation of an ECM8 based electrochemical test
system. Not to be confused with the very simple micro-controller buried within the ECM8.
System Potentiostat
This is the potentiostat responsible for making electrochemical measurements on the cells used in
the experiment. The system potentiostat is typically a fully featured computer controlled
instrument.