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The article discusses pest control techniques needed to be followed by electrical professionals for preventing damage to electric controls from pests including rats, snakes and ants. Topics discussed include behavior of pests, the necessity of using enclosures meant to protect electrical equipment with details on their types and specifications and standards for enclosures specified by the National Electrical Manufacturers Association (NEMA).

The article offers information about sizing and applying limit switches. The function of limit switches is to convert mechanical motion into an electrical signal by using a lever to force to open or close a set of electrical contacts. Information about the usage of limit switches in other variety of applications is discussed, as well as its maintenance.

The article discusses overcurrent handling in motor circuits circulations. Topics discussed include Short circuit and ground fault protection, Overload protection, use of motor full load current (FLC) or the full load amperes (FLA), actual current drawn by the motor depends on the load on the motor and on the actual operating voltage at the motor terminals.

The article presents basic steps which were required to size the branch circuit conductor. Topics discussed include the impacts of temperature on resistance of a conductor, the ampacity of branch circuit conductors and the minimum size of branch circuit conductor for continuous nonlinear load. It also informs about the rating of the device or overcurrent protection device supplied by tap conductors.

The article provides a checklist for improving the specification of the vehicle lighting system. Topics discussed include the involvement of suppliers in the development of fleet specification, the type of nominal electrical voltage supply and of circuit protection system, attention to the chassis connector, considerations for body wiring specifications, routing the wire and connectors to reduce damage, the proper location of safety lighting system, and awareness of physical damage risk areas.

The article focuses on the importance of the VXI modular solution in recent times. VXI is used in many Aero automated test systems (ATS). The VXI standard has a track record as an architecture, which can be trusted for applications who are in need of a long life cycle. The VXI board size and power budget are different from smaller formats such as PXI with a power budget

The article offers brief information about modular instruments from Agilent Technologies Inc. including M9252A DigRF host adapter, M915540 40-GHz SPDT switch and M9157CH40 40-GHz single SP6T swtich.

The article offers information on the fundamentals of current-sensing relays. It says that understanding alternating current (AC) and direct current (DC) current relays can help electrical professionals solve power quality problems effectively. It discusses the protection of equipment from overcurrents and undercurrents, the prevention of power outages from ground faults, and current transformers (CTs).

In this article, the author discusses how much on-chip transient protection is required. It highlights three major types of transients including electrostatic discharge (ESD), electrical fast transient (EFT), and surge transient. It informs that the amount of transient protection required to maintain the reliable operation of a circuit depends on the application environment in which the circuit must operate and on the type of transients that can be expected within this environment.

The article discusses the solution to a complex overvoltage problem which occurred to Dominion Virginia Power equipment. Traditional approaches to eliminate the risks of overvoltages are relocationg one of the circuits, insulating the lower circuit, and converting the lower-voltage circuit to the same voltage as the upper one. It suggests that the solution to the overvoltage problem is to detect a sustained overvoltage event and provides protection to both utility and end-use equipments.

The article examines some of the common violations electrical inspectors find in switch applications. Circuit breakers, which provide overcurrent protection as well as a switching function. Molded-case switches that resemble circuit breakers. They plug into an entrance panel and pick up power from the bus bars(s) but do not offer overcurrent protection. It notes that the terminal screw must be properly torqued.

The article discusses technological developments in the telecommunications industry as of November 2016, particularly the use of twisted-pair copper cabling systems in data and power transmission. Also cited are the effects of spark gap erosion due to unmating under power over ethernet (PoE), the jack products from technology firm Siemon to resolve spark gap issues, and such other products as the REVConnect connectivity system from cable products maker Belden.

The article discusses the significance of protection against transient voltage spikes to prevent voltage surge from destroying important equipment or bringing whole facility down. It mentions that hard-wired transient protection devices are covered by Article (Art.) 280 or Art. 285. It notes that Art. 280 refers transient protection devices as surge arresters while Art. 285 depicts them as surge-protection devices (SPDs).

The article evaluates several cable equipment and supplies including the FO-VFL fiber-optic visual fault locator from Ripley, the SES40 Service Entrance Suppression surge protector from Erico, and the WireMaster Mapper from Jewell Instruments.

The article provides information on how to determine and calculate the requirements for the motor and motor circuit protection relative to the U.S. 2008 National Electrical Code (NEC). It describes ways to protect motor from overload, calculating its branch-circuit conductor and feeder conductor size. Moreover, it discusses the considerations or requirements in protecting the branch-circuit, short-circuit and ground-fault protection.

Discusses different ways on how to run an audio using unshielded cable. Category data of audio cables; Kinds of cable shields; Benefits and disadvantages of the type shield cables.

The article focuses on the best-performing designs for high power amplifiers, which can dissipate heat. Central to the design task will be thermal management techniques that remove the heat from the MOSFET junctions in the modules, so that they operate at safe temperatures, thereby assuring maximum reliability. One of the reasons to design with three open-frame power modules in parallel rather than with a single hybrid amplifier is the benefit realized in ridding the power amplifier of heat. It is easier to conduct heat away from three distinct devices than from one. INSET: Reaping the Benefits of Open-Frame Modules.

Focuses on the types and specifications of surge protective devices (SPD) commonly used at home in the U.S. Characteristics of a quality SPD; Comparison between a fast SPD and slow SPD; Distinctions of speed response, joule rating and the kind of technology used in manufacturing protective devices.

Discusses factors to be considered when testing surge-protection devices (SPD) in the United States. Stress conditions in SPD; Blind spots in standardized test procedures; Temporary overvoltage conditions; Black box testing. INSET: What's a Blind Spot?.

Discusses a variety of components to accomplish power-supply monitoring and control. Monitoring voltages with detectors and power-on resets; Importance of monitoring overvoltage conditions; Type of voltage protection circuit; Techniques for performing voltage margining.

Discusses the way of sizing short-circuit and ground-fault protection for a feeder that supplies more than one motor. Line drawing layout to simplify a motor calculation; Determination of the size of overcurrent protection device; Mathematical expression for calculation of the ampacity of motor feeder conductor.

Part I. Focuses on motors and branch-circuit conductors. Method for providing overcurrent protection for most circuits; Motor overload protection devices; Sizing of branch-circuit conductors; Branch-circuit protection for short-circuits and ground-faults; Process to determine what percentage use to use the motor branch-circuit short-circuit ground-fault protection device.

Offers suggestions for applying power conditioning equipment to improve power quality in the United States. Importance of defining power quality problems; Verification of power source compatibility; Verification of load compatibility; Evaluation of application criteria; Protection of equipment.

Presents guidelines on applying surge protection in electrical environments. Cause of electrical surges; Duration of electrical surges and transients; Protection of data communication equipment; Protection of twisted-pair applications; Protection of coaxial applications.

Presents several electrical protective devices in the United States. Includes COMPACT NS circuit breaker, Smart Luck ground-fault circuit interrupter and Reflected Wave Trap motor protector; List of product manufacturers and advertisers; Contact information.

Presents several power conditioning equipment manufactured in the United States. Includes the E Series uninterruptible power systems, Sandwich Block voltage surge supressors and medium-voltage capacitors/filters; List of equipment manufacturers and advertisers; Contact information.

The article focuses on the use of the separate overload protection from fault and short circuit protection for motor circuits. Topics discussed include use the motor nameplate current rating (FLA), use of soft starter or a variable-frequency drive (VFD) with soft-start function, and use of the motor nameplate current for calculations.

Looks at how manufacturers and producers improve their uninterruptible power supply and surge suppressor products in the networking industry. Forms of protection provided by the two product lines; Description of the two products; Innovations made for the products' improvement. INSET: Power protection: Whose business is it?.

Presents electric protective apparatus and appliances featured in the periodical `EC&M,' and rated number fourteen by the periodical's readers. Includes transient suppression filter systems from Current Technology; Capacitor/harmonic filters from ASC Industries; Transient protection system from Siemens Energy & Automation; Online UPS from Deltec.

The article discusses the requirements for electrical installations of electric cranes and hoists as described in the National Electric Code, a standard for safe installation of electrical wiring and equipment in the U.S. Topics discussed include using a common-return conductor for a crane or hoist operated by more than one motor, keeping the conductors away from possible current paths, and sizing the branch circuit overcurrent protection devices (OCPDs) before sizing the feeder OCPDs.

The article focuses on the role of high-side load driver for the protection of short-circuit. It states that "dumb" driver control a high-power load operating at a much higher voltage without fear of destructive short-circuit conditions. It further discusses how optocoupler effectively allows the circuit to monitor the voltage across the load.

The article offers information on various changes in the 2011 U.S. National Electric Code (NE) that are related to grounding products, the protection for cable and raceway installations and direct-burial applications. It discusses the requirements for the grounding installation of rod, pipe and plate electrodes, the prohibition of the use of the equipment grounding conductors as grounding electrode conductors, and the protection of conductors, raceways and cables against physical damage.

The article provides information on the requirements for switchboards and panelboards installation as stated in Article 408 in the National Electrical Code. It mentions that when using panelboards for service equipment, it is necessary to provide each one with a main bonding jumper for the connection of the service neutral conductor to the panelboard's metal frame. It also discusses the identified closures to be used when unused openings for circuit breakers and switches are detected.

The article focuses on the efficiency of the spark-gap (SG) method in achieving low-cost energy harvesting. It states that an SG device can act as mechanical converters and potential current dividers. Its design is aimed at addressing the challenges regarding the choice of the architecture and active element and the method to get the circuit started.

The article focuses on the specifications for equipment protection of sensors and low-voltage systems. It notes that protection from short circuits that could cause damage in equipment motherboard is one of the main challenges of sensor manufacturers. It mentions that in designing subsystem protections, input voltage range, minimum current limit, and thermal dissipation are among the load-switch parameters to consider.

The article focuses on the significance of chip fuses in electrical overloads protection. It examines the principles of chip fuse design and the potential of thin-film technology to resolve issues on the stability and preciseness of fusing characteristics. Moreover, it notes the role of the fusing characteristics in determining the melting times of electrical overcurrents.

The article reports on the use of gas discharge tubes (GDTs) for optimal protection of broadband digital communication. It cites that GDTs are reliable tools in protecting telecommunications systems and equipment from lightning and power-fault conditions. It explains on how general GDT operates and how it affects telecommunications. GDT disadvantage is that it has inconsistent electrical measurements and these inconsistencies are caused by the contaminants into the gas. The article also provides diagrams depicting the GDT ramp-impulse versus dc-breakdown (DCBD) voltages and GDT's DCBD voltage performance.

The article offers information on the factors to be considered in selecting the right circuit protection for switch-mode power supplies (SMPS). It provides several recommendations to ensure proper circuit protection due to SMPS lack of inherent resistance of linear-regulator designs. Primarily, the author regards fuses as an ideal candidate for overcurrent protection in SMPS, revealing its significance for consideration. In addition, the need to accurately define the key parameters of the application which include circuit voltage, maximum normal operating current, fault current, operating temperature, pulse current and mounting/form factor is discussed. Furthermore, the three basic selection criteria in choosing the fuse is revealed.

The article discusses the features of solid-state overcurrent-protection integrated circuits (IC) which provides protection for pins at risk of overloads and short circuits. Such switches are at risk for overvoltage and even destruction if the energy stored in the stray inductance is not accounted. However, the current limit usually allows a delay time before the circuit is interrupted. Without accounting for the stored energy in stray inductance, USB devices can be subject to overvoltage.

The article focuses on the requirements of the National Electrical Code (NEC) for arc fault circuit interrupters (AFCI) in the U.S. The 2008 NEC requires arc fault circuit interrupters to be installed in additional areas of the home, including and dining rooms, living rooms, and other habitable areas. According to a report, AFCI give more protection than conventional circuit breakers.

The article deals with the need to protect wind turbines from overvoltages and currents due to lighting strikes. It describes the key features and compositions of wind-turbine installations (WTIs) in the U.S. It states that Franklin-type lightning rods can protect WTIs against direct lightning strikes. It discusses the special requirements for protecting the power-supply system between the generator and transformer station at the 400/690-V level.

The article focuses on the provisions of Article 240 known as overcurrent protection which provides the requirements for selecting and installing overcurrent protection devices (OCPDs) in the electrical industry. It informed that overcurrent would exist when current exceeds the rating of conductors resulting from overload, short circuit or ground fault. The OCPDs would protect circuit by opening when current reaches a value that would cause an excessive temperature rise in the conductors .

The article evaluates the safety of using polymeric positive-temperature-coefficient (PPTC) nonlinear thermistors in protecting electronic circuits and motors against heat and current. Compared to other fuses and fusible links, PPTC devices protect against overtemperatures and overcurrents. The devices can be used as series elements in a circuit. They are also qualified for appliance designs, comply with the UL 1434 standard and work with lead-free solders and high-volume assembly processes.

The article provides initial setup for motor circuit protectors (MCP) for branch motor circuits to protect against short circuits with the help of electronic MCP, which uses a microprocessor for the correct setting. According to NEC Corp., short-circuit protection for MCP should be not more than eight time the motor's operating current. On the other hand, MCP has a single dial called a magnetic adjustment range, which is designed to "dial back" protection after initial current in-rush.

The article discusses the mechanisms of protecting flybacks in short circuit design. The tripping of the overcurrent comparator circuit and shutting the metal-oxide semiconductor field-effect transistor (MOSFET) is the key to short-circuit protection. Leading-edge blanking can be used to avoid false overcurrent trips due to gate-drive currents or hard switching at the drain. Designers must see to it that the MOSFET can accommodate the transformer current to ensure a robust design.

The article discusses some critical design and installation rules for pole-mounted lightning-induced overvoltage protection scheme. Important parameters to consider when sizing lightning surge arresters are given like the basic impulse insulation level of a power cable and protective margin. Also, lead length is necessary in designing and installing the connections between pole-mounted surge arresters and medium-voltage cable terminators. INSET: Lightning and Underground Power and Signal Lines.

The article discusses the various sources of transient overvoltages. Transients are generally divided into two main categories: those that are derived from natural causes, such as lightning; and those generated through the use of equipment. Lightning strikes mostly induces surge on local power distribution lines causing damage to susceptible electronic equipment. Lightning can be protected with lightning arresters rated to spark over at approximately 30kV. Equipment-caused transient voltages include continuous surges, momentary surges, and capacitor switching. Continuous surges which can range from 250V to 1,000V, can come from operation of electric motors or other inductive loads. Capacitor switching is one of the main causes of oscillatory transients. One way to overcome capacitor switching is to use synchronous closing breakers or switches with pre-insertion resistors.

The article discusses the application of Electrical Code Article 525 that addresses equipment protection, wiring methods and ground fault circuit interrupter (GFCI) in amusement venues. A key provision is permiting a GFCI-protected single locking-type receptacle for a water-pump motor between five feet and 10 feet from the water. It is important to verify the equipment grounding conductor for electrical safety.

The article focuses on the prevention of a battery powered consumer product from voltage transients during charging. Transients can and do occur when an adapter is hot plugged into its battery and system load. This is due to parasitic inductance in the adapter cabling, contact fingers or printed-circuit board traces in the current path. An active-adapter integrated circuit inserted between an accessory charger and a battery powered consumer product can prevent the product from voltage transients during charging.

Investigates ways to effectively apply optocouplers in power designs. Necessity for electric circuit designers to become familiar with the various equipment-level and component-level standards that govern their use; Use of Galvanic isolation to limit transient overvoltages and to electrically segregate circuits; Basic types of galvanic isolation.