Fire alarm systems need to be inspected, tested and tagged annually. Testing must include all smoke detectors, manual pull devices, annunciators, visual indicators and strobes, control units, voice/alarm communications systems and any other devices that are a part of the fire alarm system.
it will need a port like this one to get more power from the usb since it only give 5.0 volts and this powered usb give up12 to 24 volts so you dont have that in a laptop and there is no way it could raise the power on the usb port in a laptop without damaging something .http://en.wikipedia.org/wiki/Powered_USB.
The USB spec also allows for a âsleep-and-chargeâ port, which is where the USB ports on a powered-down computer remain active. You may have noticed this on your desktop PC, where thereâs always some power flowing through the motherboard, but some laptops are also capable of sleep-and-charge.