Patent ID: 8138937

Claim:
A device for monitoring at least a grounding mechanism for an operator at a work station, said device comprising: two cascading interfaces, each having at least a first terminal and a second terminal, said first terminals of said cascading interfaces being connected together, said second terminals of said cascading interfaces being connected together; a power unit electrically connected to said first terminals of said cascading interfaces, said power unit extracting electricity from said first terminals and producing at least an appropriate direct-current voltage; a first interface having at least a first terminal; a second interface having at least a first terminal connected to said second terminals of said cascading interfaces; and a microprocessor circuit driven by said direct-current voltage and connected to said first terminal of said first interface and said first terminal of said second interface, said microprocessor circuit having at least a comparison and amplification unit, a personnel detection unit, and a microprocessor unit; wherein said comparison and amplification unit measures a resistance between said first terminal of said first interface and said first terminal of said second interface, and compares said resistance with a first reference resistance; when said resistance measured is larger than said first reference resistance, said comparison and amplification unit produces an abnormal signal; said personnel detection unit having a wireless energy detection mechanism capable of sensing the presence and absence of an operator in a coverage area and producing corresponding triggering signals respectively; said microprocessor unit activates at least one of an audio alarm and a visual alarm after receiving said abnormal signal only when said microprocessor unit has received a triggering signal specifying the presence of an operator in said coverage area and has not received a triggering signal specifying the absence of an operator in said coverage area for a period of time.