Whelen SS360 installation wiring

Looking for correct placement of purple wire to ackieve High Power on both original silver base SS360, and newer SS360C please.
Thank you

 

[NPS Ranger]

I think connecting the purple wire to +12V gave you LOW power, so leaving it unconnected should keep it in high power.

 

[dmathieu]

I'm finding that in both versions, unconnected is low power.