LONG LIFE CONTAINER TRACKING DEVICE AND METHOD FOR DETECTING MOVEMENT OF CONTAINER STRUCTURE
摘要
A tracking device is provided having a normally open passive switch for detecting when a door on a container has been opened or has been attempted to be opened. The device includes a powered communication system and the normally open passive switch that is biased toward a closed position. The switch is maintained in the normally open condition via a magnet disposed near the switch. The magnet is disposed on a rotatable container latching rod. The switch includes a magnetically reactive element coupled thereto. When the magnet is moved away from the switch, such as when the container rod is rotated, the bias in the switch will cause the switch to move to the closed position. Upon moving the switch to the closed position, the communications system will transmit a message that the door is open. When the switch is in the normally open state, the circuit on which the switch is disposed will not draw any power.