I have measured the flow (continuous variable) over a minute of a certain device A using two different testing machines B and C for a verification procedure. Each machine B and C has an error consideration of +- 0.05. The flow wave is characterised by a repeated morphology that repeats according to a frequency f. So essentially, I have two continuous signals in the time domain that should be the same but due to error are not. I want to compare the similarity of these datasets (from B and C) to see if they are significantly different. I am confused about how many variables I technically have. Do I use correlation coefficients? Do I use t tests, or perhaps Fishers z? Or something different?

Help is appreciated.