[General characteristics]
AC current sensor (CTL series) is corresponding to measure the current of very wide range with selection of usage condition. To express such concept, the output voltage characteristics use the log graph.

High current·Output saturated area

The magnetic flux density of the core is increasing proportionally to the output voltage. Thus, the output voltage becomes higher with higher load resistance or higher current for measurement, and the output linearity becomes worth at the area of saturation of core.
[CTL general series] is earning the good linearity until the high current range with using the oriented Silicon Iron of high Bs. [Figure.3]

Small current area

With small current, the ratio of exciting current toward output current in the secondary side of CT becomes higher, and then, output linearity becomes worth.
This characteristic is depended on the permeability of the magnetic material used for the core.
[CTL-Z series] for precise measurement is using the permalloy of high permeability for the core's material, and then, it can have the good output linearity until the area below 1mA. [Figure.4]

Maximum output voltage

When the output is close to the saturated area, the output linearity becomes worth and the distortion of the waveform appears. The level of the distortion toward the original waveform can be expressed as the distorted factor. The maximum output voltage in the specification is defined by the upper limit of the occurring output voltage with the criteria of 3% distortion factor, at the optimal load resistor for each sensor, and it is changed with the condition such as the measured current and load resistor. Thus, it is necessary to be examined enough.

Output waveform distortion and peak voltage

[Figure.3], [Figure.4] are expressed with the RMS value of output voltage, but it is important to know the peak voltage to interface to the electrical circuit.
The example of the output voltage waveform is described in [Figure.5] with different condition of use.
With too big load resistor or the condition of load open, the high peak voltage is occurring with magnetic saturation, although the rms value (Vrms) is small. Depended on the application, the clamped device for peak voltage or the combination of the filter condenser with converting to DC, are necessary.
It is not suitable for phase detection or peak current detection, because the repeatability of waveform is variable.