Probe 100 Plus (-Usb) Plugs into 110V AC outlet and checks for problems The P100+ Datalogger will detect all of the important types of power problems, and will Latch an LED to show them. Broadcast all data about the disturbances through the USB port as they are detected, as well as the voltage reading every second. Measures common-mode noise, Latches spikes (impulses), Latches high frequency noise Trips on Surges and Sags, Latches Power failures, and Dropouts, Determines if the outlet is wired properly