But be warned that if you tell an E150 to power-off you will have great weeping and wailing and gnashing of teeth getting it to restart. Rather drop to OBP and pull the power.
Seems to make much more sense to let it drop to the OBP and then type power-off if that's really what's needed.
--- James Whatever My niece called me "Uncle Robot" on the weekend! Giant Robot Ltd, http://www.giantrobot.co.nz/