2378results about "Continuity testing" patented technology

A method and apparatus for testing electromagnetic connectivity in a drill string are disclosed. The method includes transmitting a test signal down a transmission path in a drill string; receiving a reflection of the test signal; and determining from the reflection whether there is an interruption in the electromagnetic connectivity in the transmission path. In general, the apparatus includes a signal generator for generating a test signal into the drill string; a receiver for receiving the reflection of the test signal; and means for determining from the reflection whether there is an interruption in the electromagnetic connectivity in the transmission path. Preferably, a common coil is included through which the test signal generated by the signal generator may be transmitted into a drill string and through which a reflection of the test signal may be received.

System for monitoring an electrical system of a facility includes one or more local sensing devices, each of which is adapted to be connected to the electrical system of the facility in proximity to a respective load that receives power from the electrical system so as to make local measurements of a voltage across the load continuity measurements of electrical-power presence at one or more points in the electrical system of said facility. A processing unit is adapted to receive and compare the local measurements to reference measurements of the voltage supplied to the facility, in order to detect a fault in the electrical system.

Disclosed herein are a variety of different electrical system topologies intended to mitigate the impact of large intermittent loads on a 12 volt vehicle power distribution system. In some embodiments the intermittent load is disconnected from the remainder of the system and the voltage supplied to this load is allowed to fluctuate. In other embodiments, the voltage to critical loads is regulated independently of the voltage supplied to the remainder of the system. The different topologies described can be grouped into three categories, each corresponding to a different solution technique. One approach is to regulate the voltage to the critical loads. A second approach is to isolate the intermittent load that causes the drop in system voltage. The third approach is to use a different type of alternator that has a faster response than the conventional Lundell wound field machine.

In the voltage detecting device according to the present invention, voltage detecting lines respectively extend from a plurality of voltage input terminals, a plurality of capacitative elements are respectively interposed on coupling lines each coupling two adjacent voltage detecting lines to each other, and the voltage detecting lines are connected to a voltage detecting unit. At least all the voltage detecting lines respectively disposed on the positive electrode side of the cells are each connected to ground via one or more disconnection detection resistors. The voltage detecting unit detects a disconnection on a wire between each of a plurality of voltage detecting points of the assembled battery and a plurality of voltage input terminals based on voltage inputted from each voltage detecting line.

A battery management system includes one or more lithium ion cells in electrical connection, each said cell comprising: first and second working electrodes and one or more reference electrodes, each reference electrode electronically isolated from the working electrodes and having a separate tab or current collector exiting the cell and providing an additional terminal for electrical measurement; and a battery management system comprising a battery state-of-charge monitor, said monitor being operable for receiving information relating to the potential difference of the working electrodes and the potential of one or more of the working electrodes versus the reference electrode.

Diagnostic tools for testing integrated circuit (IC) devices, and a method of making the same. The first diagnostic tool includes a first compliant printed circuit with a plurality of contact pads configured to form an electrical interconnect at a first interface between proximal ends of contact members in the socket and contact pads on a printed circuit board (PCB). A plurality of printed conductive traces electrically couple to a plurality of the contact pads on the first compliant printed circuit. A plurality of electrical devices are printed on the first compliant printed circuit at a location external to the first interface. The electrical devices are electrically coupled to the conductive traces and programmed to provide one or more of continuity testing at the first interface or functionality of the IC devices. A second diagnostic tool includes a second compliant printed circuit electrically coupled to a surrogate IC device.

The current invention is an automatic AC power interruption system built into a portable power strip or a portable casing or integrated into an appliances control circuitry. The invention monitors the environment for hazard alarms, for example, a T3 signal smoke detector alarm, and responds by tripping open the power supply circuit to the power strip's receptacles and thus interrupts AC power to the protected appliances the user has chosen to plug into them. One alternate form of the invention uses a portable casing that can be plugged into a power receptacle and, when a hazard alarm is detected, trip off the nearest GFCI. Other alternate forms of the invention are integrated within an individual appliance's control circuitry and may interrupt power using a built-in switch or by tripping off the nearest GFCI device. The invention's purpose is to help prevent death, injury, and property damage by preventing fires or facilitating fire suppression; more particularly, by interrupting electrical power to problematic appliances, such as toasters, space heaters, battery chargers, stoves, and motors, when a hazardous condition alarm is emitted. It further interrupts power to the problematic appliances when a detector emits an alarm indicating toxic fumes, natural gas, radon, carbon monoxide, or whatever other detector-alarm the consumer installs in the area to be protected.

The battery voltage monitoring apparatus has a structure in which, for each adjacent two of battery cells, the positive electrode of the battery cell on the higher voltage side and the negative electrode of the battery cell on the lower voltage side are commonly connected to a corresponding one of common terminals provided in an RC filter circuit. The common terminal is branched into a first branch connected to one end of a first resistor and a second branch connected to one end of a second resistor, the first resistor being connected to a corresponding one of positive side detection terminals at the other end thereof, the second resistor being connected to a corresponding one of negative side detection terminals at the other end thereof. A capacitor is connected across a corresponding one of pairs of the positive side and negative side detection terminals.

The invention provides a fault detection system in a photovoltaic system (1), which uses a first measurement characteristic curve and optionally a second measurement characteristic curve to record the system status, and can thus distinguish malfunctions from the normal system operating state.

The invention discloses a matrix converter switch open circuit fault diagnosis method based on prediction control. The method comprises the following steps of under the condition that a matrix converter works normally, establishing relation models between an output voltage and an input voltage, and between an input current and a load current; determining numbers of all the switch combination states of the matrix converter; establishing a state space model and acquiring predicted values of the load current, the input current and the input voltage in a next sampling period; determining an evaluation function; using a finite set model prediction control strategy to select a switch state capable of making an evaluation function value be minimum in all the switch combination states in each sampling period and using the switch state as the switch state of the next sampling period; establishing the state space model and acquiring a change rule of a fault phase load current after a switch open circuit fault is generated; carrying out on-line monitoring on the load current, according to a finite set model, predicting and controlling the selected switch state so as to carry out fault diagnosis, and identifying a fault switch position. By using the method, an open circuit fault can be timely diagnosed.

A battery pack, a method for detecting the battery pack, a charging assembly, and an electric tool are provided for detecting voltage and disconnection of the battery cells. The battery pack may have an output voltage of at least 56V and may include a plurality of series connection units. A voltage detecting module may be utilized for detecting voltage in the battery pack. A battery control module configured to control voltage detecting module may also be employed. The method may involve determining whether the series connection units are disconnected based on rates of voltage change or internal-resistance of the series connection units.

An electric drive system in an automotive vehicle includes a controller for determining a condition of the electric drive system. The electric drive system includes only two current sensors and a common-mode current transformer. In response to the current sensors and the common-mode current transformer, the controller determines the condition of the electric drive system. The condition of the electric drive system may depend on a condition of an electrical connection between a drive system inverter and a motor in the electric drive system as well as a calculated amount of error in the electric drive system. In addition, the controller may control various operations of the electric drive system, which may or may not depend on the condition of the electric drive system.