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In order for the Microsoft Windows operating system on your computer to properly recognize a WaveDriver, WaveNow, or WaveNano potentiostat, certain device driver software must be installed on your system. This device driver software is a product developed by Future Technology Devices International, Ltd. (FTDI). The FTDI website features a driver download page from which the most recent “D2XX” driver can be obtained.

In general, installation of the driver is a simple matter of downloading the driver package and clicking on the executable file.
It may be necessary to choose the “Run as Administrator…” option when you attempt to execute the driver installer (see image).

To activate the device driver, your Windows system must “discover” the new instrument connected to your system.

For the Pine WaveDriver, WaveNow, and WaveNano potentiostats, this discovery occurs when you turn on the potentiostat and connect it to your system via a USB cable. You should force your system to discover the potentiostat at a time when you are not running the AfterMath application. When you plug in the potentiostat for the first time, you will see various messages from the Windows operating system indicating the discovery of new hardware.

Only after Windows completes the task of configuring this new hardware should you run the AfterMath application. If the driver installation is successful, then the instrument should appear in the instrument list in the lower-left corner of the AfterMath screen.

Related Software Links: AfterMath Support Page, AfterMath User Guide, AfterMath Electrochemistry Guide, AfterMath Installation Guide

Related Hardware Links: WaveDriver Potentiostat, WaveNow Potentiostat, WaveNano Potentiostat

The WaveNow USB Potentiostat is connected to an external electrochemical cell through a 15-pin cell port located on the side of the instrument. This port is a female HD-15 connector and has the same appearance as a VGA video connector on a personal computer.

Pine offers several products designed to mate with the cell port on the WaveNow USB Potentiostat:

• WaveNow/WaveNano Shielded Cell Cable Kit (part number AKCABLE5)
• WaveNow/WaveNano Student Cell Cable for use with the Student Voltammetry Cell (part number RRTPE04)
• Universal Dummy Cell for troubleshooting the potentiostat (part number AB01DUM1)
• WaveNow Universal Cell Cable Kit (part number AKCABLE3) (discontinued)

Note that some of the items listed above are sold separately.

Those users wishing to build their own cell cable for use with the WaveNow potentiostat should consult the pinout information listed in the table below. The color codes in the table refer to the standard Pine color code for electrochemical cell connections.

Related Links: WaveNow & WaveNano User's Guide, WaveNow Support Site, WaveNano Support Site

A dummy cell is a simple circuit consisting of a few resistors and capacitors which can be used to test the behavior of a potentiostat. The WaveNow (and WaveNano) potentiostats are shipped with a circuit board which contains several dummy cell circuits, each of which can easily be connected to the potentiostat via the cell port (see photo below).

The circuit board has four positions (“CELL A”, “CELL B”, “CELL C”, and “CELL D”).

Each of the dummy cell positions has the same basic circuit (see schematic diagram below), but they differ with respect to the exact resistor and capacitor values in the circuit. A table on the back side of the dummy cell lists the resistor and capacitor values, and this information is also available in the tabs below.

By using various settings of the five dip switches, it is possible to test the potentiostat against a variety of different loads, each of which might mimic the load presented by a “real” electrochemical cell. In each configuration, the reference electrode is separated from the reference sense point (TP5, TP7, or TP9) by a resistor (Rref), and the counter electrode is also separated from this point by a resistor (Rctr, or solution resistance). Similarly, the working electrode is separated from the working sense point (TP6, TP8, or TP10) by a small resistor (Ruw). Note that Ruw value may be reduced to 0 by closing the switch DIP4, and Rref and Rctr may be reduced by joining the reference and counter electrodes together by closing the DIP1 switch.

There are three configurations that are most useful for testing the behavior of a potentiostat (see table below). Note that the original factory settings for the dip switches correspond to the Randle's Circuit configuration.

Dummy Cell Dip Configurations

Pure Resistive Load

The most basic configuration is Pure Resistive Load, where a resistor is used to mimick the charge transfer resistance (Rct) at the electrode/electrolyte interface. A cyclic voltammogram obtained using this dummy cell configuration should show straight line with the slope inversely proportional to the Rct resistance (see below).

Pure Capacitive Load

A Pure Capacitive Load is used to simulate an electrode double layer that is ideally polarizable. The charging current, i_DL, observed when using this capacitive load is given by the following equation,

i_DL = C_DL v

where the capacitance, C_DL, mimicks the double-layer capacitance, and the working electrode potential is being swept at a constant rate, v. Very small charging currents can be produced using lower sweep rates. This is useful when evaluating a potentiostat's ability to measure small currents. An example “voltammogram” obtained using the Pure Capacitive Load configuration is shown below.

Note how the “voltammogram” appears as a rectangular box, and the height of the box (along the vertical axis) is twice the value of the charging current calculated according to the above equation. The oscillations at points where the sweeping potential suddenly switches direction are quite noticable when using a pure capacitive load. Most “real” electrochemical cells are less prone to exhibiting such oscillations.

Randle’s Circuit

A Randle's circuit places the the double-layer capacitance (C_dl) in parallel with the charge transfer resistance (R_ct) and another impedance element known as a Warburg element. The Warburg element cannot be simulated using simple resistors and capacitors because it represents the “real” diffusion processes which occur in an actual solution in an electrochemical cell.

The Randle's Circuit configuration for the dummy cell omits the Warburg element, but includes the parallel double-layer capacitance and charge transfer resistance. The response from this pseudo-Randle's cell is shown below.

Part numbers are provided below.