Systems and methods for monitoring current anomaly are described. In an example, a device can measure first current flowing along a first liner between an instrument to an equipment. The device can measure second current flowing along a second line between the equipment to the instrument. The device can compare the measurements of the first current and the second current. The device can identify a presence of current anomaly based on the comparison of the measurements of the first and second currents. The device can, in response to the presence of the current anomaly, disconnect the instrument from the equipment.

A device includes a control circuit, a scope circuit, a first logic gate and a second logic gate. The control circuit is configured to generate a first control signal according to a voltage signal and a delayed signal. The scope circuit is configured to generate a first current signal in response to the first control signal and the voltage signal. The first logic gate is configured to perform a first logical operation on the voltage signal and one of the voltage signal and the delayed signal to generate a second control signal. The second logical gate configured to perform a second logical operation on the second control signal and a test control signal to generate a second current signal.

A device includes a control circuit, a scope circuit, a first logic gate and a second logic gate. The control circuit is configured to generate a first control signal according to a voltage signal and a delayed signal. The scope circuit is configured to generate a first current signal in response to the first control signal and the voltage signal. The first logic gate is configured to perform a first logical operation on the voltage signal and one of the voltage signal and the delayed signal to generate a second control signal. The second logical gate configured to perform a second logical operation on the second control signal and a test control signal to generate a second current signal.

An electromagnetic wave identification device includes a detection section for detecting an electromagnetic wave signal which is output from an antenna for detecting electromagnetic waves and whose level is equal to or greater than a predetermined level; a measurement and record section for recording and storing the detected electromagnetic wave waveform data; and an analysis and evaluation section for receiving the recorded and stored electromagnetic wave waveform data, normalizing the electromagnetic wave waveform data by an maximum amplitude value to obtain normalized data, and determining whether or not the received electromagnetic wave is a direct wave by reference to the normalized data. The analysis and evaluation section determines whether or not the received electromagnetic wave is a direct wave by obtaining a kurtosis from a histogram of amplitude values of the normalized data and determining whether or not the kurtosis is equal to or greater than a predetermined threshold, or by obtaining a normal probability plot from the normalized data and determining whether a value of the normalized data at a predetermined probability is equal to or greater than, or equal to or less than, a predetermined threshold.

An electromagnetic wave identification device includes a detection section for detecting an electromagnetic wave signal which is output from an antenna for detecting electromagnetic waves and whose level is equal to or greater than a predetermined level; a measurement and record section for recording and storing the detected electromagnetic wave waveform data; and an analysis and evaluation section for receiving the recorded and stored electromagnetic wave waveform data, normalizing the electromagnetic wave waveform data by an maximum amplitude value to obtain normalized data, and determining whether or not the received electromagnetic wave is a direct wave by reference to the normalized data. The analysis and evaluation section determines whether or not the received electromagnetic wave is a direct wave by obtaining a kurtosis from a histogram of amplitude values of the normalized data and determining whether or not the kurtosis is equal to or greater than a predetermined threshold, or by obtaining a normal probability plot from the normalized data and determining whether a value of the normalized data at a predetermined probability is equal to or greater than, or equal to or less than, a predetermined threshold.

The present disclosure relates to a hand-held voltmeter measuring a peak voltage of a high voltage pulse applied to an electric fence. The voltmeter includes a body case of which one side has an opening, a sensor case protruded from the opening of the body case, a voltage divider disposed over the inside and the outside of the sensor case for dividing the high voltage pulse into a low divided voltage, a peak detector for detecting the peak voltage of the divided voltage, a display unit for displaying the peak voltage, and an MCU for controlling the input and the output of the elements constituting the voltmeter. According to the present disclosure, an electric fence voltmeter that measures the peak voltage accurately without need to make a ground connection to the earth, and has a low risk of an electric shock during a measurement is provided.

Disclosed is a mechanism for reducing noise caused by an analog to digital conversion in a test and measurement system. An adaptive linear filter is generated based on a converted digital signal and measured signal noise. The adaptive linear filter includes a randomness suppression factor for alleviating statistical errors caused by a comparison of a signal circularity coefficient and a noise circularity coefficient in the adaptive linear filter. The adaptive linear filter is applied to the digital signal along with a stomp filter and a suppression clamp filter. The digital signal may be displayed in a complex frequency domain along with depictions of the adaptive linear filter frequency response and corresponding circularity coefficients. The display may be animated to allow a user to view the signal and/or filters in the frequency domain at different times.

A method for displaying sensor readings in a measurement instrument having an array of display elements initially divides the range of interest of the sensor reading into a plurality of consecutive sub-ranges and determines a scaling function for displaying sensor readings for each sub-range. For each sensor reading, the appropriate sub-range is determined into which the sensor reading falls (where N is the number of this sub-range). The scaling function for the Nth sub-range is applied to display the sensor reading using N consecutive display elements. Optionally, the system may include a visual or audible indicator for the use when the display rolls from one sub-range to another. The display may also include feature indicating the peak sensor reading encountered.

A method for displaying sensor readings in a measurement instrument having an array of display elements initially divides the range of interest of the sensor reading into a plurality of consecutive sub-ranges and determines a scaling function for displaying sensor readings for each sub-range. For each sensor reading, the appropriate sub-range is determined into which the sensor reading falls (where N is the number of this sub-range). The scaling function for the Nth sub-range is applied to display the sensor reading using N consecutive display elements. Optionally, the system may include a visual or audible indicator for the use when the display rolls from one sub-range to another. The display may also include feature indicating the peak sensor reading encountered.

A probe or accessory for use with an electrical test and measurement instrument can include an input to receive an input signal from a device under test (DUT), a clamp control unit or oscilloscope to apply a clamping/limiting level to the input signal to generate an output signal, and/or a control unit output port to provide the clamped/limited output signal to an oscilloscope.