Editor’s note: This briefing was written by Admiral Instruments. Admiral Instruments will be exhibiting (booth 309) at the 233rd ECS Meeting in Seattle, WA this May. See a list of all our exhibitors.
You’ve probably heard your potentiostat ‘click’ while running a cyclic voltammetry experiment or similar sweep methods. Have you ever wondered where that clicking comes from, and why it happens?
The clicking sound is made by a series of electromechanical relays (AKA switches) when they turn on or off to direct the flow of current (I) to a different shunt resistor. A shunt resistor is a specialized resistor with high accuracy and a low temperature coefficient. In most commercially-available potentiostats, current is not directly measured. Rather, current readings are calculated by dividing the voltage drop (V) across the shunt resistor by the resistance (R) of the shunt resistor.
I = V/R