BitLocker with TPM and PIN - Laptop shuts down after 60 seconds

Whenever I use BitLocker with a TPM+PIN, at the BitLocker PIN entry prompt, my Dell E6440 shuts down after 60 seconds. Is this just an added security measure or what?

Do you guys ever run across this same issue?

Thx!

My Lenovo does this as well. I'm guessing it's a power-saving feature.

Is there anything one can do about this?

I haven't tried it but according to Windows 8.1 Bitlocker - automatic shutdown during password prompt
you can run the following from an admin console:

Code:

bcdedit /set {bootmgr} bootshutdowndisabled 1