Some users believe that cables are simple and therefore should be inexpensive. However, as critical components of the measurement system, this is an incorrect assumption.
The cell connection cable is often overlooked when considering the quality of measurement, yet it can be just as important as the following signal processing stages in delivering high accuracy signal measurements, particularly at the extremes of an instrument’s capability.
When the ModuLab-ECS system entered the initial design phase, it quickly became clear that ‘off-the-shelf’ cables from component suppliers would not be suitable for this research grade Potentiostat/FRA. We therefore worked in close partnership with a specialist cable company to develop a cable set unique to the ModuLab-ECS. Highlights of the design of these cables include:
- Stability resistors inserted inside the cable to greatly improve the performance of the control loop
- LEMO connectors allowing multiple carrier signals in one cable
- Triax shielded cables for ultra low current measurements
As an example of the effect of cables on a measurement, compare the two impedance results on a high impedance cell overleaf. The plots below clearly demonstrate that using a specially screened cable such as the ModuLab-ECS triax working electrode cable, significantly improves the performance of the measurement system. Note particularly the level of noise (especially in the phase values) of the measurement made using standard coaxial cable vs. that with the triax cable at frequencies below 0.1 Hz
Blue and Purple Lines = Triax (Magnitude and Phase)
Red and Green Lines = Coax (Magnitude and Phase)
Cell cables are an important part of a measurement system and consequently they are not inexpensive.