Abstract: The present invention relates generally to systems, devices and methods for the efficient use of utilities, more particularly to the distribution and provision of electricity supply at appropriate voltages, monitoring and usage by end devices, and to facilitating consumers in changing their energy usage behaviour, and to adopt and easily install appropriate sustainable, energy efficient or renewable technologies. Said end devices typically including traditional electric, electronic and lighting appliances requiring AC or DC power provision or low voltage DC power via AC/DC converters.

Abstract: A boot control circuit of a computer system is provided. The boot control circuit is coupled to a system power module. The boot control circuit includes a connection port module and a motherboard. The connection port module includes a detection pin. The motherboard includes a switch for controlling the system power module. The motherboard controls the system power module to provide power for booting the computer system according to a connection between the detection pin and the switch.

Abstract: A grinder includes a motor including an output shaft, a housing accommodating the motor, a switch, a brake member movable back and forth between a rear braking position and a front brake release position, a switch lever movable between an initial position and a depressed position, a sliding member slidable between a first position to move the brake member to the brake release position and a second position to move the brake member to the braking position to turn on the switch at the first position and turn off the switch at the second position, and a link member rotatable between a first rotational position to move the sliding member to the first position and a second rotational position to move the sliding member to the second position.

Abstract: A base plate for a medical appliance includes a top layer; a first adhesive layer with a water soluble or water swellable hydrocolloid; an electrode assembly having a plurality of electrodes; and a monitor interface for connecting the base plate to a monitor device. The monitor interface has a coupling part with an elastically deformable part that allows the coupling part to move relative to the first adhesive layer of the base plate for coupling the monitor device and the base plate.

Abstract: There is provided an apparatus (20) for monitoring a condition of an electrical power transmission medium (22), the apparatus (20) comprising: a signal source (24) for transmitting a signal (30) to travel along the electrical power transmission medium (22); and a monitoring device (26) configured to detect one or more reflected signals (34) in the electrical power transmission medium (22), wherein the monitoring device (24) is configured to use the or each detected reflected signal (34) to determine a change in capacitance of the electrical power transmission medium (22).

Abstract: A data storage device includes a power supply circuit configured to supply power to the data storage device. The power supply circuit includes a voltage clamp configured to operate in a conduction state in response to an over-voltage condition of the power supply circuit. The power supply circuit also includes a fuse in series with the voltage clamp. The fuse is configured to open in response to a current flow through the fuse and the voltage clamp exceeding a threshold value. The power supply circuit also includes a switching device that is configured to latch in a forward conduction mode in response to the voltage clamp operating in the conduction state. The switching device couples power from a positive voltage bus to the voltage clamp when the switching device is in the forward conduction mode.

Abstract: A photovoltaic system, a method for locating devices in a photovoltaic string, a MLPE apparatus, and a method for ranking MLPE apparatuses. Each MLPE apparatus sends, actively according to a predetermine rule, an initial message to the other MLPE apparatuses. The initial message includes a serial number corresponding to said MLPE apparatus and an accumulated operation duration of said MLPE apparatus. The MLPE apparatuses determine the rank of the accumulated operation duration of each MLPE apparatus according to the initial messages sent from all MLPE apparatuses. After each MLPE apparatus communicates with a communication host, the MLPE apparatuses reports the rank of the accumulated operation duration of each MLPE apparatus to the communication host. Thereby, the communication host may determine a physical location of each device in the photovoltaic string according to the ranks of the accumulated operation durations and a sequence of installing positions of the devices in the photovoltaic string.

Abstract: A side looking occupancy sensor is incorporated in a conventional wall switch mounted into a switch box adjacent to a door. The side-looking proximity sensor preferably is mountable to either side of the doorjamb to make the side-looking proximity sensor face the door opening. During operation, the side-looking sensor monitors the door movement or senses the passage of a person for indication that a person is entering or leaving the space. Entry and exit determination is made based on activation of the side-looking sensor.

Abstract: Disclosed are power distribution systems and methods in which a power distribution unit (PDU) is provided with an overcurrent protection device and per-outlet current sensing at each of the multiple electrical outlets of the PDU. The described embodiments enable the identification of the electronic device connected to a specific outlet or electronic device that may have caused the overcurrent protection device to trip. The methods of outlet identification in a PDU having multiple electrical outlets includes detecting whether either a peak current or a half-cycle root mean square (RMS) current at each outlet has exceeded a selected threshold prior to the occurrence of the trip event associated with the overcurrent protection device.

Abstract: A building system for training a prediction model with augmented training data. The building system comprising one or more memory devices configured to store instructions thereon that, when executed by one or more processors, cause the one or more processors to obtain a first training data set comprising data values associated with a data point of the building system and with a plurality of time-steps and energy values associated with consumption of the building system at each of the plurality of time-steps; generate an augmented training data set comprising a second training data set, the second training data set comprising the energy values and the data values of the first training data set but with a data value replaced with a predetermined value at a time-step of the plurality of time-steps; and generate a prediction model by training the prediction model.

Abstract: A non-transitory computer readable storage medium in an energy control system includes instructions stored thereon that, upon execution by a processor, cause the processor to receive a request for station power from a requesting power plant of a plurality of power plants, determine a burden score associated with supplying the station power to the requesting power plant from two or more supplier power plants of the plurality of power plants, allocate available power from the supplier power plant having the lowest burden score to the requesting power plant, and provide a notification to an operator of the supplier power plant having the lowest burden score. The notification indicating the amount of power expected to be supplied to the requesting power plant.

Abstract: There is provided a light control circuit including a light detector, a frequency detector, an error amplifier, an NMOS driver and a light source. The frequency detector identifies a signal frequency according to detected voltage signals outputted by the light detector and generates a control signal accordingly. The NMOS driver changes a drive current of the light source according to an output of the error amplifier. The error amplifier changes a bandwidth thereof according to the control signal from the frequency detector to regulate a response time of the drive current of the light source.

Abstract: An electronic cable system operates as an extension cable to facilitate external viewing of internal infrastructure LED status. A wired cable is provided having a first end and a second end, the first end including a first I/O coupler, LED detectors and a power jack; and the second end including a second I/O coupler and a plurality of LEDs. The plurality of LEDs of the second end illuminate in response to activation of the LED detector of the first end. The first I/O coupler may plug into an internal module of electronic infrastructure, such as a server, to detect operational status of the internal module via the LED detectors. The second I/O coupler may couple to infrastructure housing, permitting the plurality of LEDs to be viewed externally of the housing. The plurality of external LEDs on the infrastructure housing mimic internal (non-viewable) status indicator LEDs of the internal module.

Abstract: A method for identifying a signal transmission device includes: reading attribute information from a memory device by a first device of a signal processing system, wherein the attribute information records information regarding at least one attribute of the signal transmission device that is coupled between the first device and a second device of the signal processing system; determining the at least one attribute of the signal transmission device by the first device according to the attribute information; and setting a maximum value or a minimum value of a signal output by the first device or the second device according to the at least one attribute.

Abstract: The present disclosure provides a method, performed in an accessory device, for communicating a leakage state of an ostomy appliance, wherein the accessory device comprises an interface configured to communicate with one or more devices of an ostomy system, the one or more devices comprising a monitor device, and/or the ostomy appliance configured to be placed on a skin surface of a user. The method comprises obtaining monitor data from the one or more devices, the monitor data being indicative of presence of fluid at a proximal side of a first adhesive layer of the ostomy appliance towards the skin surface; determining a leakage state at the proximal side of the first adhesive layer of the ostomy appliance based on the monitor data, and communicating the leakage state of the ostomy appliance via the interface.

Abstract: In accordance with aspects of the present disclosure, a system of monitoring one or more consumer goods is provided. The system includes at least one monitoring device configured to capture and transmit data about the one or more consumer goods and at least one computing device configured to receive data from the at least one monitoring device, perform analysis on the captured data, and generate one or more notifications or triggers based on the analysis.

Abstract: Example electric appliance identification methods and apparatuses are provided. One example method includes obtaining, by a power line communication (PLC) device, a first noise signal in a circuit. The PLC device can then obtain first data based on the first noise signal, where the first data is used to describe a time-frequency feature of the first noise signal. The PLC device can then obtain, based on an electric appliance identification model and the first data, an electric appliance identification result corresponding to the first noise signal, where the electric appliance identification model is obtained based on a signal including a second noise signal of at least one known electric appliance.

Abstract: A method for analyzing survivability of an infrastructure link includes determining an optimal path arrangement of the infrastructure link between two geographic locations; and determining a risk index associated with the determined optimal path arrangement based on one or more quantified cost factors and one or more quantified risk factors associated with the determined optimal path arrangement. The risk index represents a survivability of the infrastructure link.

Abstract: An integrated magnetometer comprises at least one field sensor unit including a first transducer element for generating, in response to a detected magnetic field, a first electrical output signal. At least one gradient sensor unit of the magnetometer includes at least a pair of second transducer elements which are arranged to detect the magnetic field at two different locations and generate, in response to the detected magnetic field, a second electrical output signal. The first and second transducer elements are formed on a common substrate and are encompassed by a common protective layer and/or housing.

Abstract: A leak may be detected in a heat exchanger of a hemodialysis device. A drain valve is opened by the controller, and then closed by the controller after a pre-selected time period. An initial pressure is determined in the spent dialysate circuit and stored in the memory. A system pressure is determined at periodic time intervals and compared to a pre-determined maximum pressure. The controller then determines whether the heat exchanger has a leak, in that in response to the system pressure exceeding a predetermined maximum pressure, a command is generated to execute an event including suspending a disinfectant operation with a disinfecting agent, and in response to the initial pressure subtracted from the system pressure being greater than a predetermined minimum pressure differential, a command is generated to execute an event including suspending the cleanse operation with the disinfecting agent.

Abstract: A method and apparatus for analyzing power devices in a circuit are disclosed. In one embodiment, a power analysis apparatus analyzes information on power supplied to the circuit and classifies the power patterns into groups of their own similar power patterns by making reference to the information on the power patterns, so as to acquire at least one piece of motif information which is information on at least one fingerprint. The apparatus further counts the frequency of occurrence of each motif and determines a pair of specific motifs having the difference between the counted frequencies of occurrence, which is within a predetermined value range, and average power variation values symmetrical to each other, whereby an accurate determination can be made as to the individual power devices in the circuit.

Abstract: Systems, methods, and devices are provided to control an electrical component of an electric power distribution system with an intelligent electronic device using electrical measurements from a wireless electrical measurement device located away from the electrical component. One such system includes a capacitor bank on a lateral of an electric power distribution system, a first set of one or more wireless electrical measurement devices that obtain one or more electrical measurements of a first feeder of the electric power distribution system, and a capacitor bank controller. The capacitor bank controller may use the one or more electrical measurements of the first feeder to control the capacitor bank on the lateral.

Abstract: Embodiments implement non-intrusive load monitoring using ensemble machine learning techniques. A first trained machine learning model configured to disaggregate target device energy usage from source location energy usage and a second trained machine learning model configured to detect device energy usage from source location energy usage can be stored, where the first trained machine learning model is trained to predict an amount of energy usage for the target device and the second trained machine learning model is trained to predict when a target device has used energy. Source location energy usage over a period of time can be received, where the source location energy usage includes energy consumed by the target device. An amount of disaggregated target device energy usage over the period of time can be predicted, using the first and second trained machine learning models, based on the received source location energy usage.

Abstract: Techniques are provided for generating score(s) and/or correction(s) for a digital twin representing a utility network. One or more bridges transform data, from a plurality of system and associated with a utility network, to a different format, e.g., relational database format. A process generates a digital twin of the utility network utilizing the data in the different format. A data quality service (DQS) performs evaluations and/or analyses of the digital twin to generate a baseline score and an updated score representing a state of the digital twin if corrections are applied. If the updated score meets or is above a threshold value, the DQS automatically applies and save the corrections to the digital twin. If the updated score does not meet the threshold value, the DQS presents a failure notification and one or more graphical representations of the utility network such that incremental corrections can be made.

Abstract: A fuel dispenser includes a power distribution system having an alternating current (AC) power supply and an AC to direct current (DC) power converter configured to convert a portion of the AC power to DC power for one or more DC peripheral components associated with the fuel dispenser. The power distribution system also includes processing circuitry configured to power down at least one of the DC peripheral components in response to an actuator, cause an indicator to be activated indicating that the DC peripheral components are de-energized and the AC power supply is active, power up the at least one direct current peripheral component in response to the actuator when the direct current peripherals are de-energized, and cause the indicator to be activated to indicate that both the DC peripheral components and the AC power supply are active.

Abstract: Disclosed is an electrical dimmer that upon activation sends a forward-phase modulated test power pulse to a connected load, receives from the load a response pulse, compares the width of the two pulses, and, depending upon the results of the comparison, operates in either forward- or reverse-phase modulation. The dimmer may respond to an intensity target by setting a pulse-width modulation duty cycle, the setting based on an intensity-translation curve. The translation curve may be based on a mapping between luminance and human visual perception of brightness. Some dimmers support a minimum intensity setting, and some dimmers configure themselves to the frequency of the incoming alternating-current power source.

Abstract: A side looking occupancy sensor is incorporated in a conventional wall switch mounted into a switch box adjacent to a door. The side-looking proximity sensor preferably is mountable to either side of the doorjamb to make the side-looking proximity sensor face the door opening. During operation, the side-looking sensor monitors the door movement or senses the passage of a person for indication that a person is entering or leaving the space. Entry and exit determination is made based on activation of the side-looking sensor.

Abstract: The invention relates to a system and method for separating pieces having a second density (9c) from granular material. The system includes a separation tank (2) comprising a first side wall (12) provided with a tank outlet (6), a bottom (7), a pipe (4) defining a channel (3a) for allowing a slurry to enter the tank (2). A pipe outlet (4b) is spaced apart from the tank outlet and arranged vertically below the outlet (6). The separation tank (2) comprises a trap (5) for collecting said pieces. A separation chamber (8a) is arranged in liquid communication with the pipe outlet to allow slurry to enter the separation chamber. The pipe outlet is in a lower third of the separation tank facing the bottom of the tank so that slurry flows vertically through the pipe outlet towards the bottom causing a turbulent flow of the slurry in the tank.

Abstract: A controller in an electricity storage system that includes a first DC/DC converter connected to a storage battery, and a bidirectional inverter connected to the first DC/DC converter. The controller includes a control circuit which changes a content to be displayed by a display, according to whether the electricity storage system is in a predetermined state in which a first PV is connected to the bidirectional inverter via a DC bus.

Abstract: A light switch apparatus includes a network communication unit and an output unit. The network communication unit is configured to receive electricity price rate server information from a server, and generate a first high range electricity price output data and a second low range electricity price rate data according to the electricity price rate server information. The output unit is configured to display at least a first output color in response to receiving the first high range electricity price output data from the network communication unit, and a second output color in response to receiving the second low range electricity price rate data from the network communication unit.

Abstract: A system for monitoring an electrical device and a method thereof is provided, wherein at least one primary unit is connected with an input side and/or an output side of the electrical device and configured to obtain electrical parameters of the electrical device. A secondary unit is connected with each primary unit and configured to receive the electrical parameters obtained by the primary unit, store the electrical parameters to form a repository of previously obtained electrical parameters, compare the electrical parameters with previously obtained electrical parameters to determine any deviation in the electrical parameters and correlate the deviation in electrical parameters with a list of impending faults to identify any impending fault. The secondary unit based upon the correlation of the electrical parameters generates a summary and/or alert indicative of state of the electrical device by way of alerts, notifications etc.

Abstract: Systems and methods for securing transaction messages are described. In an example, a rule set may be accessed. The rule set may specify a selection of a key from a plurality of keys or an obfuscation process from a plurality of obfuscation processes. The selection may be based on a condition associated with securing transaction messages. The keys or the obfuscation processes may be stored at a card reader. An instruction about the selection may be provided to the card reader based on the rule set and a determination that the condition is satisfied. In turn, a secure transaction message may be received from the card reader. The secure transaction message may have been secured based on the key or the obfuscation process. The secure transaction message may be provided to a transaction system that includes a management system associated with the key or the obfuscation process.

Abstract: A processing method and LED module based on a power line transmission amplitude-modulated signal, which comprises a voltage processing module, a voltage regulator module, a control module, a constant current module, a signal comparison module, an oscillator and an LED, wherein an amplitude-modulated signal having a high and low level is input from a positive electrode terminal and then processed by the voltage processing module for input to the voltage regulator module, a power supply voltage is provided respectively for the LED and the control module under the effect of the voltage regulator module, and a reference voltage is provided for the signal comparison module; the amplitude-modulated signal is input to the signal comparison module, such that a control signal is obtained under the effect of the signal comparison module for input to the control module. In the invention, the LED emits light stably, and can be automatically produced.

Abstract: A distributed automation control system includes a network for connecting members of the system to a central server for communication between the members and the central server. The members can include a device controlled by a microcontroller in communication with the network, a mobile object digitized to communicate with the central server via the network, and a facility component in communication with the central server. A member can be assigned to one or more groups of members for group learning and for generating a group heartbeat. Each member defines a safety volume which is monitored by the central server. When the safety volume of one member overlaps the safety volume of another member, the central server initiates a responsive action which can include ceasing the operation of at least one of the members.

Abstract: A distributed automation control system includes a network for connecting members of the system to a central server for communication between the members and the central server. The members can include a device controlled by a microcontroller in communication with the network, a mobile object digitized to communicate with the central server via the network, and a facility component in communication with the central server. A member can be assigned to one or more groups of members for group learning and for generating a group heartbeat. Each member defines a safety volume which is monitored by the central server. When the safety volume of one member overlaps the safety volume of another member, the central server initiates a responsive action which can include ceasing the operation of at least one of the members.

Abstract: A proximity sensor, and a portable device equipped therewith, with at least two sense electrodes, one influencing the other. By reading twice the capacity of one electrode, while either setting the potential of the counter-electrode to guard or letting it float, the sensor of the invention discriminates between a body part, or another electrically equivalent object, and low-permittivity objects.

Abstract: A request to monitor a data packet to be transmitted from a first location to a second location over a first network is received. A projected time for the transmission of the data packet from the first location to the second location is determined. Responsive to determining the projected time, whether the data packet arrived at the second location after the projected time plus a variance is determined.

Abstract: A system and method used to detect voltage by an electric field detector on equipment is provided. The equipment includes a component which is configured to come into direct contact with, or come into proximity of, a conductor of electricity, and a control system which is in operative communication with the component. An electric field detector is provided on the equipment. The detector includes field detection circuitry configured to detect a voltage in an electric field in the environment which meets or exceeds a voltage threshold. When an overvoltage is detected by the electric field detector, the control system of the equipment is configured to act by performing one of 1) activating a warning module on the equipment and 2) causing the component of the equipment to act.

Abstract: Systems and methods for operating an Electronic Smart Tag (“EST”). The methods involve: operating the EST in a first operational state in which first item related information is output from an electronic output device of the EST that is powered by an energy storage device storing energy harvested from an external energy source; detecting when a charge level of the energy storage device reaches or falls below a first threshold level; and transitioning an operational state of the EST from the first operational state to a second operation state in which a message is output from EST requesting that a mobile device be placed in proximity to the EST for purposes of obtaining at least a first portion of the first item related information, in response to the detection that the charge level of the energy storage device has reached or fallen below the first threshold level.

Abstract: Devices in an environment may be transitioned to a low power state based on calendar data or other types of user input. User input indicating a first device, a time period, and a set of conditions is received. When the time period occurs, device data from one or more devices in the environment is used to determine whether the set of conditions is met. If the conditions are met, an instruction from a device outside of the environment is provided to the first device to cause the first device to enter a low power state, during which the device is no longer accessible to other devices outside of the environment. After a lapse of the time period, a change in conditions, or in response to manual input provided to the first device, the first device returns to an operational state.

Abstract: A method for checking an operability of two-wire measuring transducers in automation technology which output a measurement signal as an impressed loop direct current via a two-wire line and active assemblies of which are supplied with electrical energy via the two-wire line includes: measuring the loop direct current and an input voltage of the measuring transducer; increasing the loop direct current in a range from a minimum value to a maximum value independently of the measured value, while measuring the input voltage of the measuring transducer; storing the measured values of the input voltage at selected measuring points of the loop direct current as an individual signature of the measuring transducer; and, during ongoing operation, measuring the input voltage at connection terminals of the two-wire line via an internal resistance of the measuring transducer at a prevailing loop direct current and recursively comparing that with the signature.

Abstract: A power transmission device includes a power transmission unit configured to transmit electric power to a plurality of power reception devices, a communication unit configured to exchange charging information with the plurality of power reception devices, a determination unit configured to determine based on the charging information, for each of the plurality of power reception devices, whether the power reception device is capable of limiting power reception, a detection unit configured to detect based on the charging information, for each of the plurality of power reception devices, completion of charging of the power reception device, and a control unit configured to perform control so that power transmission is stopped in a case where the detection unit detects that at least one power reception device incapable of limiting power reception has completed charging.

Abstract: The invention concerns a switching system (6) for activating and deactivating of an electrical appliance (100) comprising a remote switch control device (9) that comprises a first terminal (90) electrically connected to a first power line (8), a second terminal (91) electrically connected to a second power line (7), and a third terminal (92) connectable to an electrical 5 terminal of the electrical appliance. The remote switch control device (9) is configured to modify the electrical connection between the first and the third terminal (90, 92) in response to a detection of an attenuation of an electrical parameter between the first and second terminals (90,91) caused by a electromechanical switch (1) configured to be manually actionable by 10 a user. The invention further concerns the remote switch control device (9) and a method for installing a switching system using the remote switch control device (9) and the electromechanical switch.

Abstract: The present invention is directed to systems and methods for performing energy disaggregation of a whole-house energy usage waveform, based at least in part on the whole-house energy usage profile, training data, and predetermined generic models, including: a module for pairing impulses identified in the whole-house energy usage waveform to indicate an appliance cycle, pairing impulses with at least one up transition with at least one down transition; a module for bundling impulses that are representative of an appliance cycle; a classification module, which upon determination of a type of appliance associated with bundles, is configured to classify the bundles of transitions in accordance with bundles exhibited by similar appliances with similar characteristics; and utilizing such pairing module and module for bundling to perform energy disaggregation.

Abstract: A communication hub that manages communication signals and sensor signals is provided. Communication signal gateways receive and transmit the communication signals with a plurality of different communication signal formats. Sensor signal gateways in turn receive the sensor signals with a plurality of different sensor signal formats. The controller dynamically interfaces the different communication signal formats of the received communication signals with a communication hub signal format to establish communication links with the communication systems associated with the received communication signals. The controller further dynamically interfaces the different sensor signal formats of the received sensor signals into the communication hub signal format used by the communication hub to gather sensor information. The controller further establishes at least one routing path to a destination hub using at least one of the established communication links.

Abstract: A method and apparatus for managing power for devices that may be part of a group is provided herein. During operation a power-management device will transmit a power-management message to a device or group of devices. The message indicates a time period (keep-alive time) and critical services that are to be kept operating for the keep-alive time. In response, the device(s) that receive the message may transmit an information message indicating whether or not a device has enough power to run the services for the keep-alive time.

Abstract: The invention provides a wire clamping-type connection structure of a power supply and a light source board, which is in the field of lamp manufacturing. A wire clamping-type connection structure between a power supply and a light source board, comprises: a power supply and a light source board connected to the power supply via wires, and each one of the wire clamping grooves welded at one of power input points on the light source board, each of the plurality of threading holes arranged near the power input points on the edge of the light source board and each of the clamping pieces arranged on the plurality of threading holes.

Abstract: A power tool is provided including an elongated housing. The housing includes a motor case disposed at a front end thereof and a handle portion extending along a longitudinal axis of the housing from the motor case to a rear end of the housing. The handle portion includes two elongated walls extending from the motor case along the longitudinal axis of the housing to form a planar opening within the handle portion. A partition wall is arranged along an axis substantially perpendicular to the longitudinal axis of the housing, separating the handle portion from the motor case. An electric motor having a drive shaft is mounted within the motor case, and a module casing supporting a planar circuit board is received within the planar opening and supported by the elongated walls within the handle portion of the housing axially along the longitudinal axis of the housing.

Abstract: A system, an alternative system, and a computer readable storage medium, for a power outage notification system that proactively manages communication of power outage alerts messages to customers of a power distribution system. Wireless communications between smart meters at the edge of an electrical power distribution network and a proactive outage alerts processing engine at an outage alerts notification information processing system facilitate management of communications of power outage alerts messages to customer communication devices. Power outage alerts messages can be communicated to customers using email messaging, text messaging, and voice mail messaging.

Abstract: A handheld grinder includes an elongated housing, an electric motor, an output shaft, a wall, a planar circuit board, and a motor drive circuit. The elongated housing defines a cavity therein and includes a motor case disposed at a front end and a handle portion to a rear end. The electric motor has a drive shaft that is mounted within the motor case. The output shaft is drivably coupled to the drive shaft of the electric motor. The wall separates the cavity between the motor case and the handle portion of the housing. The planar circuit board is disposed in the handle portion of the housing. The motor drive circuit is accommodated entirely within the handle portion of the housing on the planar circuit board.