Embodiments of the invention are directed to using a DC multimeter configured for checking device amperage. A DC voltmeter is electrically-connected in series with the DC multimeter. A linear circuit is electrically connected in series between the DC multimeter and the DC voltmeter. A device under test is electrically-connected between positive and negative terminals of the DC voltmeter.

A reel device is a casing device for rollingly storing wire. The casing has a turnplate and is coupled with a measuring model. The measuring model has a function of testing the external circuit or power source plug and providing warning or presenting information regarding the external circuit or power source plug.

A device for performing electrical measurements according to the present disclosure includes a first input post that is electrically conducting, a second input post that is electrically conducting, and a sleeve that is electrically insulating and at least partially surrounds the first input post and the second input post. The sleeve includes a first rib extending in a longitudinal direction of the sleeve and a second rib extending in the longitudinal direction of the sleeve. The first rib and the second rib are constructed to separate the first input post and the second input post.

A voltage measurement and/or overvoltage protection circuit for a measurement instrument comprising a measurement channel with at least one termination resistor and a measurement port is provided. Said voltage measurement and/or overvoltage protection circuit comprises at least one resistor. In this context, the voltage measurement and/or overvoltage protection circuit is contactable to the measurement port via said at least one resistor. In addition to this, a resistance of the at least one resistor is higher than a maximum resistance of the at least one termination resistor.

The present invention relates to an active probe (1) for measuring a voltage across a high value impedance, said probe (1) comprising: an impedance matching circuit (10) configured, on the one hand, to have an input impedance at least 100 times higher than the impedance to be measured and, on the other hand, to deliver a low impedance signal at the output; a probe tip (6) configured to take a measurement and connected to said impedance matching circuit (10); a ground reference (G) connected to said impedance matching circuit (10); said impedance matching circuit (10) comprising, connected in cascade, at least one input circuit (14) and a non-inverting amplifier circuit (16) adapted to high impedance values.

A digital multimeter stores multiple sequential measurements of physical or electrical parameters. Each of the sequential measurements has a name including an automatically generated descriptor. The descriptor for each sequential measurement may indicate a relative position of the measurement within the sequence. For instance, the descriptor may indicate whether the measurement was obtained before or after other measurements in the sequence.

A Rogowski coil in a sensor unit has voltage induced by a conductor surrounded by the Rogowski coil. The voltage is integrated to represent current which is converted to digital data representing current in the conductor and sent wirelessly to a multimeter. The sensor unit may receive control signals from the multimeter and a remote control apparatus. A plurality of sensor units may be networked and controlled by the remote control apparatus.

An apparatus for a system power device utilized in an interconnected power system. The interconnected power system may include multiple system power devices connected to various inter connections of groups of direct currents (DC) from power sources which also may be connected in various series, parallel, series parallel and parallel series combinations for example. The apparatus may include a processor connected to a memory and a communication interface operatively attached to the processor. The communication interface may be adapted to connect to a mobile computing system of a user in close proximity to the system power devices. A graphical user interface (GUI) of the mobile computing system may allow various operational and re-configuration options for the interconnected power system which may include installation, maintenance and monitoring schedules in the interconnected power system when the user of the GUI is in close proximity to the system power devices.

An electrical sensor is described. The electrical sensor including an electrical signal input configured to receive an electrical signal, an alarm, one or more inputs configured to set a configuration value corresponding to one or more indicators on the electrical sensor, and monitor. The monitor is coupled with the electrical signal input, the alarm, and the one or more inputs. Further, the monitor is configured to determine a characteristic of the electrical signal received on the electrical signal input. And, the monitor is configured to activate the alarm based on the configuration value set by the one or more inputs and the characteristic of the electrical signal.

A multi-meter including a current input, a common input, a display, a first current measurement circuit, a second current measurement circuit, and a controller. The controller includes a first input and a second input. The controller operable to receive a first voltage from the first current measurement circuit at the first input, receive a second voltage from the second current measurement circuit at the second input, determine a value for a current being measured based on the first voltage if the first voltage is below a predetermined threshold, determine a value for a current being measured based on the second voltage if the first voltage is above the predetermined threshold, generate an output signal related to the determined value for the current, and provide the output signal to the display.