Power monitor with indicators
AssigneeWoodhead Industries, Inc.
InventorsJoseph F. Murphy, Harry L. Dexter, Nicolas D. L. Jones
Life of this patent
Estimating the term…
Abstract
A device for monitoring power conditions in the power leads of a communication network or power distribution bus includes a microprocessor 54 which measures the voltage on the power leads and computers a filtered bus voltage, Vbus, and a time-averaged bus voltage, Vave. From these, the microprocessor determines whether overvoltage, undervoltage or ripple conditions exist to actuate associated visual indicator intermittently (LEDs 57, 58, 59), or surge, brownout or transient conditions to actuate the associated indicators (LEDs 57, 58, 59) constantly for their associated slot times in a display cycle. The device may be in the form of a compatible terminator or a Tee for the network or power bus.
Claims11
Apparatus for monitoring power on an electrical DC power bus including at least first and second power leads comprising:
- a microprocessor coupled to said leads and receiving signals representative of the voltage across said leads, said microprocessor being programmed to periodically sample the voltage signals on said leads and to generate Vbus data representative of bus voltage;
- a plurality of visual indicator devices;
- said microprocessor being programmed to compute a first signal representative of an overvoltage condition when Vbus exceeds a predetermined overvoltage threshold value and to actuate one of said visual indicator devices to provide a visually distinctive signal for so long as said overvoltage condition is detected, and a second signal representative of a power surge condition when Vbus exceeds a predetermined level for a predetermined time period and then returns to a normal voltage range, said microprocessor thereupon latching said second signal while actuating one of said indicator devices in a second visually distinctive signal;
- said microprocessor being programmed to compute a third signal representative of an undervoltage condition when said Vbus signal is less than a predetermined undervoltage threshold, and to actuate one of said indicators with a third visually distinctive signal;
- said microprocessor being programmed to compute a fourth signal representative of a brownout condition when said Vbus signal falls below said undervoltage level for a predetermined period and thereafter returns to a normal voltage range, said microprocessor latching said fourth signal while actuating one of said indicator devices to display a fourth visually distinctive signal.
Apparatus for monitoring power on an electrical DC power bus including at least first and second power leads comprising:
- a microprocessor coupled to said leads and receiving signals representative of the voltage on said leads, said microprocessor being programmed to periodically sample the voltage signals on said leads and to generate Vbus data representative of bus voltage;
- at least one visual indicator device;
- said microprocessor being programmed to compute a first signal representative of an overvoltage condition when Vbus exceeds a predetermined overvoltage threshold value and to actuate said one visual indicator device in a first time slot of a visual display cycle comprising a plurality of slots occurring seriatim, said display cycle determined by said microprocessor to provide a first visual signal for so long as said overvoltage condition is detected, and a second visual signal distinctive from said first visual signal in a second time slot of said display cycle and representative of a power surge condition when Vbus exceeds a predetermined level for a predetermined time period and then returns to a normal voltage range, said microprocessor latching said second signal, whereby said first visual signal is displayed in said first time slot and only for so long as the associated condition exists, and said second visual signal is displayed in said second time slot once the associated condition is detected and until reset.
Dependencies are inferred from the claim text.