Gamry Instruments EIS Box, Руководство оператора, Страница: 32 / 52

Cell Connections
32
Table 6-1
Cell Cable Terminations
Color Type Name Normal Connection
Blue Banana Plug Working Sense Connect to working electrode
Green Banana Plug Working Electrode Connect to working electrode
White Banana Plug Reference Connect to counter electrode
Red Banana Plug Counter Electrode Connect to counter electrode
Connect both the blue and green cell leads to the positive terminal (usually). The working electrode is the
electrode being tested. The blue plug connection senses the voltage of the working electrode. The green
working electrode connection carries the cell current. The working electrode may be as much as 520 mV above
the circuitry ground (floating ground).
Connect the white plug to the negative terminal (usually). The measured cell potential is the potential
difference between the blue and white cell connectors.
Connect the red banana plug to the negative terminal also. The counter-electrode terminal is the output of the
EIS Box
’ s power amplifier.
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 reduce noise in your data by connecting the EIS Box
’s Floating Ground to an earth ground.
Membrane Cell Connections
The EIS Box can be used with membrane cells. In this type of cell, a membrane separates two electrolyte
solutions. Two reference electrodes are used: one in each electrolyte. Each electrolyte also contains a counter
electrode. The EIS Box controls the potential across the membrane. Table 6-2 shows the cell connections used
with a membrane type cell.
Caution:
If any electrode in your cell is at earth ground, never connect the EIS Box
Protective Ground to System (floating) Ground. Autoclaves, stress apparatus, and field measurements may
involve earth-grounded electrodes. water pipe can be a suitable earth ground.
Warning:
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 EIS Box to an incorrect and unsafe voltage can create a safety hazard (see Chapter 1 for
details).