It goes without saying that a current sensor, regardless if it’s a split core or solid core, has to be very accurate. This can be achieved either by having core built with high-quality, expensive materials and manufacturing processes; or by getting a device that is easy enough to calibrate on various kinds of electrical measurement systems.
Accuracy, in turn, brings up the issue of drift, or the ability of the sensor to maintain an accurate reading over a long period. Sensor readings can be affected by changes in temperature and humidity, as well as the age and condition of the electrical system’s components. A sensor that is highly insensitive to these factors is ideal.
Sometimes, even the strength of the current can affect the sensor’s accuracy, which means that the device should also do well in terms of linearity, or its ability to work with a wide range of high and low currents.
Related to accuracy and linearity is a factor known as phase shift. This refers to the phenomenon where electrical currents suddenly have a different waveform after its initial run through in a circuit; especially an input/output circuit. To maintain accuracy, a current sensor should have a low phase shift as much as possible.
Current sensors should also be easy to install and be compatible with most other electrical systems. Easy integration means shorter working times, which can be enough to offset the huge cost that the best current sensors come in.