Avoid External Noise Sources; Length And Construction Of The Cell Cable; Lead Placement - Gamry Instruments Interface 1010 Operator's Manual

Measurement of Small Signals – Hints for System and Cell Design
A Faraday shield is a conductive enclosure that surrounds the cell. The shield can be constructed from sheet
metal, fine mesh wire screen, or even conductive paint on plastic. It must be continuous and completely
surround the cell. Don't forget the areas above and below the cell. All parts of the shield must be electrically
connected. You will need an opening in the shield large enough to allow a cell cable to enter the shield.
Gamry offers a Faraday cage called the Faraday Shield™ that features a transparent window so you can see
your electrochemical test during operation. It can be used with any potentiostat.
The Faraday Shield must be electrically connected to the Interface 1010's Floating Ground terminal.
An additional connection of both the shield and the Interface 1010 Floating Ground to an earth ground may
also prove helpful.
Only connect the Interface 1010 ground to earth ground if all components of the conductive
cell are well isolated from earth ground. A glass cell is usually well isolated. An autoclave is generally not
well isolated.

Avoid External Noise Sources

Try to keep your system away from sources of electrical noise. Some of the worst are:
• Fluorescent lights
•
Motors
•
Radio transmitters
•
Computers and computer monitors
Try to avoid AC-powered or computerized apparatus within your Faraday shield.

Length and Construction of the Cell Cable

The Interface 1010 is shipped with a 60 cm shielded cell cable. We also offer extended length cables and a
special cable for low-impedance cells as choices at extra cost.
Cell cables longer than 1 meter will result in degraded instrument performance. Increased noise and decreased
stability both can occur. However, with most cells, the instrument will work acceptably with an extended cell
cable, so our advice is to go ahead and try it. As a rule, do not use current-interrupt IR-compensation with cell
cables longer than 5 m.
Do not use the Interface 1010 with any cables not supplied by Gamry Instruments. The Interface 1010 cable is
not a simple cable like a typical computer cable. The Interface 1010 cable includes a number of individually
shielded wires contained within an overall shield. We pay careful attention to issues such as shield isolation,
isolation resistance, and capacitance.
If you need a special cable, contact us with your requirements.

Lead Placement

Many experiments with the Interface 1010 involve cells with small capacitances, the value of which may be
important.
In these cases, the capacitance between the Interface 1010 cell leads can result in an error. The Interface 1010
alligator clips can have 10 pF or more of mutual capacitance if they are run alongside each other.
If you wish to avoid excessive capacitance:
• Place the leads as far apart as possible. Pay special attention to physical separation between the
working electrode and working sense leads and the counter/ counter sense/reference electrode leads.
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