DSO scope triggering these days amazing capability.
In the case of L load switching, like a relay coil, two main methods. One to select
V triggering, set a value, then modify as necessary to observe different parts of
the capture sample record. Or use PW, >, something on the order of 1 mS to
start with.
You can even set triggering to start at n'th transient. Lots of possibilities.
http://www.syscompdesign.com/assets/Images/AppNotes/relay-demo.pdfStart by selecting trigger mode, set sweep to "normal" mode, and change the
trigger value until you get a triggered display. This is if you are cycling the
relay at some rate. Then move on to a single shot to get one display cycle you
can print out.
If you are not cycling the relay then set scope for Vtrigger, set that at just a
little less than power supply, say 11.5 V for a 12 V supply. Or 12.5 V. Then turn
on, or off, that should initiate a trigger you can then work with and start to
modify as necessary.
A dso captures a buffer of samples, then the software using trigger settings displays
that part of the buffer that starts with/meets the trigger condition.
Regards, Dana.