| 摘要 |
A monitor for a light circuit comprising a power source, a light being monitored, and a sense resistor. A first voltage amplifier circuit connected to the light circuit has a first output signal representing the voltage across the sense resistor. A second voltage amplifier circuit connected to the circuit has a second output signal representing the voltage across the sense resistor. A microprocessor is configured to receive the output signals from the first and second voltage measuring circuit and is programmed to calculate the current to the light based on the first and second digital output signals, compare the calculated current against a threshold current, and initiate a failure signal if the calculated current is less than the threshold current. A visual indicator activates if the microprocessor initiates a failure signal, whereby the activated indicator notifies that the light is not operating correctly. The calculated current is based on the first output signal if the light is a low current light, and the current is calculated is based on the second output signal if the light is a high current light. The calculated current can be a function of the measured voltage of the power source. The threshold current can be a percentage of a calibrated current, which is based on a measured voltage across the sense resistor when the light is operating correctly.
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