Here I am posting a three phase waveform, as induced by a phase convertor...It is a small motor driving a larger motor, the larger motor has two legs of single phase power (180 degrees apart) inducing a voltage 90 degrees from each, between them. I had been studying the three phase power before my friend built this. We use the PICO with attenuators. This waveform is horrible and I dont see how it could work but it does drive the three phase equipment it was designed for.
If youy do some research of your own, you will see what I mean by horrible. The phases are not 120 degrees apart and they run the equipment? They do.
So, I have seen you post running compression captures where you have marked the duration between rulers; like the time differences between peak compression and exhaust stroke but not in mSeconds, rather degrees. I want to mark this waveform for degrees or as Hz. Can you help me with that?
   Pardon me, the small motor drives only long enough to get the larger motor spinning. Once it is traveling at speed, single phase applied to it creates a 'three phase' power source for to drive equipment with...it becomes driven by the two legs of single phase and induces the third leg; that which is between them. The larger motor will now spin itself. Look up phase converter please.
That is, the smaller motor drives the larger until it is spinning and then the larger - a three phase motor - will drive itself and also serve as a power supply to other equipment. The larger motor is roughly twice the power rating of the equipmnent it is used to drive. The smaller motor has a timed shut-off.

I wish PICO made a device for this scope that plugged in between it and measured for to affect attenuated safety. Ordinarily, there isn't spikes that will rise to the 2000 volts. If you work where you will operate three phase equipment and you own a PICO you will be tempted to hook up as we did. We hooked up to a non-live circuit, completed the settings and then turned it on. Oh yeah, there are apps from some of the master auto technicians you can download for reading running compression waveforms. Perhaps I can adapt something to read 360 degrees. You can see the PICO has a setting to measure RMS; that is AC power as "ROOT MEAN SQUARE". Your 120V AC power that powers your small drill press is measured in RMS Peak voltage is higher. RMS is not an average,,,but read up on it for yourself.
I just called our friend Murray who engineered the phase convertor...now remember, we are running the three phase motor with two legs of single phase at 180 degrees phase angle from each other ones negative peak is the polar opposite of the others positive peak, and they induce the third leg, B... it does not even resemble three phases of healthy power but it is running the equipment.
Noticing that legs A and C are RMS 93V and B is 153V, we are going to measure two more measures , one of the same but with reference to actual earth (we will grind some steel of this steel work shed's frame somewhere and another measurement of power to the switch before it closes and delivers the two legs of single phase. Capiche?
What I posted is the voltage after the switch closes...

There are other differential probes too. How much do you want for that Trevor? Oh I see, between 4 and 5 hundred dollars. I need to wait