Outlet Groups don't turn off if I manually shutdown operating system before power loss

[jimzat_apc]

We are a machine tool manufacturer and have two (2) Windows 7 User Interface Computers connected to our machine and powered by a single SMT1500 with an NMC.  Things are configured so that after being on battery for 5 minutes, shutdown signals are sent to both PC and then 2 minutes later the Outlet Groups are powered down.

When simulating a loss of power event by removing factory power, the OSes shutdown gracefully and the UPS's power outlets turn off.

If the operator knows they are bringing the machine down (for maintenance, etc.) and they shutdown Windows before removing machine power, the UPS's power outlets remain on until the battery drains.  If the service to the machine completes before the battery is drained and machine power is restored, the User Interface computers DO NOT boot in response to the AC restoration since their power supply NEVER saw a loss of power.

How can I get the outlets to turn off in the second scenario so that the power restoration is identified by the PCs?

 - JimZat