A contact resistance test device includes a set of full fins providing channels between a source region and a drain region and a set of partial fins connected to the source region. A gate structure is formed over the set of full fins and set of partial fins. A source contact is connected to the source region. A probe contact is isolated from the source contact and is connected to the source region wherein a voltage measured on the probe contact measures contact resistance when a drain-to-source current is flowing in the set of full fins.

A motor driving device includes: a converter unit having a capacitor; a plurality of inverter units having a plurality of semiconductor switching elements and configured to convert a capacitor voltage across the capacitor into an AC voltage to drive a plurality of motors; a second switch configured to connect the negative-side terminal of the capacitor to ground; a first detector configured to detect a ground-referenced voltage; and a second detector configured to detect the capacitor voltage. The motor driving device controls the semiconductor switching elements to establish a measurement state for enabling measuring of the insulation resistance of a measurement target motor, estimates a convergence value of the ground-referenced voltage based on multiple measurements of the ground-referenced voltage detected by the first detector, and then calculates the insulation resistance based on the estimated convergence value and the capacitor voltage.

Embodiments presented in this disclosure generally relate to a ground device. More specifically, embodiments disclosed herein are directed to a grounding device for indicating whether there is proper grounding for electrical equipment. One embodiment presented in this disclosure provides an apparatus. The apparatus generally includes a lug configured to be coupled to a physical ground node, the lug having one or more bolts for coupling the lug to a surface of a plate such that the physical ground node is electrically coupled to an electrical ground node. The apparatus also includes a sensing circuit configured to detect whether the physical ground node is electrically coupled to the electrical ground node, and provide an indication of whether the physical ground node is electrically coupled to the electrical ground node based on the detection.

An ungrounded measurement possibility determination device that determines whether to ground a measuring instrument when measuring a voltage to ground of electromagnetic noise includes a determination table 35 in which a relationship between a measured frequency and an allowable value of the voltage to ground has been recorded, a first electrode 31 arranged on a floor of a room where the voltage to ground is to be measured, a second electrode 32 arranged on the floor, an oscillation unit 33 that inputs a frequency signal having the same frequency as the measured frequency to the first electrode 31, a voltage measurement unit 34 that measures a voltage value of a frequency signal induced by the second electrode 32, and a determination unit 36 that compares the voltage value induced by the second electrode 32 with the allowable value and determines that it is unnecessary to ground the measuring instrument for measuring the voltage to ground at a corresponding frequency in a case where the voltage value is larger than the allowable value.

A vehicle includes an Alternating Current (AC) source, a receptacle, and a switch. The AC source has a line and neutral potential. The receptacle is carried by a body of the vehicle and includes line, neutral, and ground conductors, and a ground fault interrupter (GFI) circuit. The switch is coupled between the AC source and the GFI circuit configured to selectively short the neutral and ground conductors.

The invention relates to a control valve for adjusting a process fluid flow of a process plant, comprising a valve housing (8) with a valve seat (14) and a valve member (16) connected to a valve rod (18), which cooperates with the valve seat (14) for opening and closing the control valve (2), wherein the valve rod (18) is electrically connected to the valve housing (8) through a contact device (42,43, 45). The invention is characterized in that a measuring device (26) for the ohmic transition resistance measurement of the contact device (42, 43, 45) is provided, and that the measuring device (26) is arranged in a measuring line (24) that connects the valve housing (8) to the valve rod (18).

The invention relates to a control valve for adjusting a process fluid flow of a process plant, comprising a valve housing (8) with a valve seat (14) and a valve member (16) connected to a valve rod (18), which cooperates with the valve seat (14) for opening and closing the control valve (2), wherein the valve rod (18) is electrically connected to the valve housing (8) through a contact device (42,43, 45). The invention is characterized in that a measuring device (26) for the ohmic transition resistance measurement of the contact device (42, 43, 45) is provided, and that the measuring device (26) is arranged in a measuring line (24) that connects the valve housing (8) to the valve rod (18).

A method for measuring insulation resistance in an inverter that has a DC link circuit and a bridge circuit, connected to the DC link circuit, for driving an AC current via a bridge center tap is disclosed. The method includes connecting the bridge center tap to a grounding point, successively connecting, by way of the bridge circuit, the bridge center tap that is connected to the grounding point to two points of the ungrounded DC link circuit that differ in terms of voltage, and measuring the current flowing from the two points that differ in terms of voltage to the grounding point. The two points of the ungrounded DC link circuit that differ in terms of voltage are selected from a group of points that includes at least one intermediate voltage point of the DC link circuit in addition to two end points of the DC link circuit, such that the voltages present between the two points that differ in terms of voltage and the grounding point do not exceed a predefined voltage limit value.

Embodiments disclosed herein are directed towards systems and methods for electric current leakage detection in a land seismic system. Embodiments may include generating at least one test signal using a digital to analog converter DAC circuitry, wherein the DAC circuitry includes an output operatively connected to earth ground. Embodiments may further include alternately grounding a positive path to an analog to digital converter ADC circuitry during a first time window and a negative path to the analog to digital converter during a second time window while measuring an ADC signal. Embodiments may also include determining an average amplitude of the first time window and the second time window and determining a leakage resistance based upon, at least in part, the average amplitude of the first time window and the second time window.

Embodiments disclosed herein are directed towards systems and methods for electric current leakage detection in a land seismic system. Embodiments may include generating at least one test signal using a digital to analog converter DAC circuitry, wherein the DAC circuitry includes an output operatively connected to earth ground. Embodiments may further include alternately grounding a positive path to an analog to digital converter ADC circuitry during a first time window and a negative path to the analog to digital converter during a second time window while measuring an ADC signal. Embodiments may also include determining an average amplitude of the first time window and the second time window and determining a leakage resistance based upon, at least in part, the average amplitude of the first time window and the second time window.