Let's assume we have a CNC machine cutting an aluminium block and we are monitoring its RMS power consumption at a constant sample rate e.g. 1Hz (see figure below for example). Can this considered to be a time-series signal? This link states that time-series should show some internal structure, others could argue that any signal observed over time can be described as time-series.
If the example above is not a time-series, what else could you call that signal?