Watchdog circuit for transmission line sensor module
First Claim
1. A device for monitoring at least one parameter of a power transmission line for transmitting alternating current comprising:
- means for sensing values of said parameters;
means coupled to said sensing means for processing said values;
memory means coupled to said processing means for storing said processed values;
means for deriving energy from said transmission line for powering said device;
means coupled to said means for deriving energy from said transmission line for converting alternating current into direct current;
means coupled to said means for converting for supplying power to said processing means and said memory means;
means for controlling said means for supplying power to said processing means and said memory means;
said means for controlling including means for receiving a periodic signal indicating normal device operation and being responsive to said periodic signal for continuously enabling said means for supplying power to supply power to said processing means and said memory means; and
said means for controlling further including means responsive to sustained absence of said periodic signal indicating abnormal device operation for disabling said means for supplying power to said processing means and said memory means for a fixed time period and for subsequently enabling said means for supplying power to said processing means and said memory means;
wherebysaid processing means and said memory means are powered down and subsequently powered up following an indication of abnormal device operation.
2 Assignments
0 Petitions
Accused Products
Abstract
A self contained sensor module mounted on a power transmission line. The module is capable of measuring various parameters such as line current, voltage, conductor temperature, and ambient temperature. The parameter values are processed by sensor electronics which digitize and periodically transmit the values to a ground receiver. The sensor electronics include MOS integrated circuits which are sensitive to fluctuations in supply voltage and which may enter a power-fail state or latch up as a result of such fluctuations. The module contains watchdog circuitry which monitors the operation of the module. If an interruption in the module'"'"'s normal operating sequence occurs, the watchdog circuit resets the MOS integrated circuits by initiating a power down/power up sequence. The module further includes current limiting circuitry that reduces the integrated circuit'"'"'s supply voltage in response to the failure of a circuit that is not critical to the module'"'"'s normal operating sequence.
32 Citations
9 Claims
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1. A device for monitoring at least one parameter of a power transmission line for transmitting alternating current comprising:
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means for sensing values of said parameters; means coupled to said sensing means for processing said values; memory means coupled to said processing means for storing said processed values; means for deriving energy from said transmission line for powering said device; means coupled to said means for deriving energy from said transmission line for converting alternating current into direct current; means coupled to said means for converting for supplying power to said processing means and said memory means; means for controlling said means for supplying power to said processing means and said memory means; said means for controlling including means for receiving a periodic signal indicating normal device operation and being responsive to said periodic signal for continuously enabling said means for supplying power to supply power to said processing means and said memory means; and said means for controlling further including means responsive to sustained absence of said periodic signal indicating abnormal device operation for disabling said means for supplying power to said processing means and said memory means for a fixed time period and for subsequently enabling said means for supplying power to said processing means and said memory means;
wherebysaid processing means and said memory means are powered down and subsequently powered up following an indication of abnormal device operation. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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Specification