US Patent 7411317 Electrical load status detection and control device

An electrical load status detection and control device includes a first power supply circuit loop with a first switch, a second power supply circuit loop with a second switch, a no-load status detection unit connected with the second power supply circuit loop for detecting the current passing through the second power supply circuit loop and thereby generating a current detection signal. A micro-controller connected with a reference current value database, the no-load status detection unit, the first switch and the second switch, which receives the current detection signal from the no-load status detection unit. The micro-controller generates a switching signal to actuate the first switch and the second switch to thereby open the first power supply circuit loop and the second power supply circuit loop when detecting the current passing through the second power supply circuit loop out of the reference current value range of the reference current value database.