Aerotech RMS delay, dumb question

I did a search and couldn't find anything. What is the start time for an Aerotech delay? I know the delay starts burning at motor ignition (or before) and I was wondering, say a H128W-10, is that 10 seconds from ignition or from motor burnout?

From what I've observed, the motor's burn time is also part of the delay. My reasoning for that being that the delay for an F22-7 is noticeably longer than a G64-7. They both use the same case (29/40-120), have the same factory delay, but significantly different burn times. The F burns for 3.5 seconds and the G for about 2 seconds. That would explain why the F's delay grain would need to be longer. However, I am not an expert on rocket motors and it might be more complex than that.

Anyway, the number is from burnout. I should probably have just started with that.

Delay times are always stated as the length of time after motor burnout.

In a composite motor the delay grain actually starts burning at ignition, but that's taken into account in the delay spec. If you have a 2 second burn time, a 10 second delay is actually 12 seconds from ignition.

I have lots of videos from keychain cam rocket flights and I'd have to say that the delay starts burning at ignition and if it's a 10 sec delay it's pretty close to 10 seconds. I have one video of a rocket that sat on the pad and chuffed for three seconds then 7 seconds later zippered my rocket cause it used up 3 seconds of the 10 second delay on the pad.

[video=youtube;SC_xsHFZrDc]https://www.youtube.com/watch?v=SC_xsHFZrDc[/video]