Abstract: A method and apparatus including indicators and a Ground Fault Current Interrupter (GFCI) are provided to test the marina's power and the boats electrical system load to make sure that both are proper and safe to be inter-connected. A low voltage high impedance ground current path including an oppositely connected pair of typically four silicon diodes in series in each of the pairs, sufficient to raise the voltage to a safe level encompassing the typical combined AC ground fault and DC galvanic currents in a Marina is incorporated. This protects against low level AC ground faults present in the marina, as well as DC current due to the harbor safety ground interconnect between boats in the harbor.

Abstract: A protective system for reducing the possibility of injury to individuals or damage to electrical equipment due to a fault in a coaxial drop cable connected between a tap unit receiving both RF signals and AC power from a main distribution line and a premise unit coupling the RF signals to RF receiving equipment and the AC power to other AC powered equipment at user premises. The tap unit includes a circuit having a first line connected at spaced points to an inner conductor with the RF signals flowing through the inner conductor and the AC power flowing through the first line. A regulated monitoring current flows from an AC to DC converter in the first line to a difference amplifier having a pair of inputs with a resistor connected between the two, whereby the difference amplifier serves to monitor the monitoring current by measuring the voltage drop across the resistor.

Abstract: It is an object to provide a semiconductor device comprising a short circuit protecting system capable of enhancing the detection precision of a collector current, thereby carrying out a reliable short circuit protection. An IGBT (1) having a collector (C) connected to a terminal (T1) and an emitter (E) connected to a terminal (T2) is provided, and has a sense emitter (SE) connected to a terminal (T2) through a variable resistor (VR1) to be a current and voltage converting section. A sense potential is output from an end on the sense emitter (SE) side of the variable resistor (VR1) and is given to a terminal (T11) of a current ratio detecting section (15). A gate of the IGBT (1) is connected to a terminal (T3) and an output of the current ratio detecting section (15) is connected to a terminal (T4).

Abstract: Current and voltage values (uk, ik) are measured for protection of an electrical power line (1). An adaptive estimator is used to analyze all the values within a measurement window, and to convert them to impedance values (Z). The line (1) is switched off if the impedance values (Z) assume unacceptable values. In order to shorten the reaction time, a warning signal (W) is produced if powerful radio-frequency signals are detected on the line (1). When the warning signal (W) occurs, the respective measurement window is located such that its start matches the time of the warning signal (W), and/or the respective measurement window is shortened.

Abstract: A circuit breaker includes separable contacts, an operating mechanism, a power supply, and a trip mechanism powered from a first power supply output. A power supply monitor circuit includes a terminal adapted for electrical connection to a ground, a first resistor electrically connected in series with a power supply regulator, a first transistor having an output and two inputs electrically connected in parallel with the first resistor, a first capacitor electrically connected between the first power supply output and the first transistor output, a second resistor electrically connected in series with the first capacitor between power supply outputs, a second transistor having a first input electrically interconnected with the first transistor output, a second input and an output, a diode electrically connected between the terminal and the second transistor second input, and an interface between the second transistor output and a trip mechanism input for disabling the tripping.

Abstract: A system for supplementing existing safety devices in light circuits by real-time monitoring of current and voltage levels in light circuits to diagnose and pinpoint problems in the circuit, and to activate a safety disconnect in the event hazardous conditions are detected. The system includes a monitor device electrically coupled to a light circuit service panel. The monitor device includes a switching means complementary to an existing disconnect means operable to independently disconnect a light circuit from a power source, and input means for collecting real-time data from a plurality of circuits. The input means includes a means for detecting unequal current levels in the light circuits, a means for continuous surveillance of ground wire continuity for each light circuit, and means for continuous sensing of the current and voltage levels in each light circuit.

Abstract: A protection apparatus for protecting electrical and electronic equipment from damage due to disturbances introduced by external electrical conductors. The apparatus employs one or more of the following methods to switch an interfacing relay from the operating state to the protected state: Surge protection; detection of the sound of an approaching thunderstorm. The apparatus may include a means to manually select either the protected state in which the connected equipment is disconnected from the external conductors, the override state in which the connected equipment is connected to the external conductors and the sensing systems are overridden and the normal operating state in which the sensing systems are employed to automatically disconnect the equipment in the event of a disturbance.

Abstract: Disclosed is a vehicle which includes an electrical system monitoring system which results in detecting arcing in the electrical distribution system of the vehicle and the ability to provide notification and protection for such arcing. The system functions to monitor the electrical distribution system of the vehicle to sense the frequencies of signals in the system using appropriate filtering. One type of filtering which may be used is based upon a heterodyning circuit which provides variable frequency filtering for filtering a signal representative of the current in at least one electrical circuit of the vehicle. The heterodyning circuit output is configured to produce a signal which may be logarithmically related to the filtered signal. If the output signal exceeds a predetermined limit (representative of noise) for a predetermined period (representative of a typical arc duration), the system generates an arc signal.

Abstract: A protective circuit for a series circuit of a power semiconductor and an inductive load, to which a freewheeling circuit of a freewheeling diode and a reverse polarity protection semiconductor switch connected in series is connected in parallel. The power semiconductor output stage may be switched on and off depending on a predetermined setpoint value with a pulse-width modulated control signal and the reverse polarity protection semiconductor switch may be made non-conducting via a charging pump when the polarity of the supply voltage is reversed.

Abstract: A phase control switch apparatus incorporating a phase-based break/make controller (80A, 80B, 80C) for protecting a reactive load such as a transformer (10) from transient surge phenomena taking place upon power-supply breaking/making operation.

Abstract: A method of reconizing a fault current in a control unit and to a control unit having a circuit for recognizing the fault current. According to the invention, a current flowing into the control unit which could cause the control unit to be damaged or to operate incorrectly is detected and a fault signal is produced depending on the current detected, the fault signal causing the load or the current supply for the control unit to be switched off, for example.

Abstract: By finding a voltage difference &Dgr;V between the maximum value and the minimum value of voltage of each cell constituting a battery set and then combining the voltage difference &Dgr;V with current I passing through the battery set into a value pair and store a plurality of the value pairs, the relationship between the voltage difference &Dgr;V and the current I is a relation represented by a straight line with the slope &Dgr;R thereof corresponding to an internal-resistance difference. Therefore, fault in the battery set can be determined from the magnitude of the slope &Dgr;R computed by a least-squares method. Fault determination for a battery set is made more accurate because variations in electromotive force caused by charge-and-discharge patterns and by changes in temperature are canceled when the voltage difference &Dgr;V is determined.

Abstract: Power arithmetic apparatus detects a first variation amount of a voltage in proportion to a voltage of a measuring object and a second variation amount of a voltage in proportion to a current of the measuring object, and calculates power of the measuring object based on the first variation amount detected and the second variation amount detected.

Abstract: An electric power monitoring device that senses power system voltages by capacitive coupling to one or more power system conductors. The capacitive coupling may be embodied by wrapping a conductive material around the insulating covering of a power system conductor. A capacitor is connected between the conductive material and a reference voltage to form a simple voltage divider. The voltage across the capacitor is proportional to the power system voltage and is used as an information signal which is analyzed by a microprocessor, after being converted to digital form by an analog-to-digital converter. Standard current transformers may be used to provide current information signals, which are also analyzed by the microprocessor. Operating power may be derived from one or more of the current information signals generated by current transformers. The power monitor requires no direct connections to power system conductors and requires no separate source of operating power.

Abstract: A fault is located in a transmission line with a sending end, a receiving end, and a plurality of tapped nodes, and multiple tapped loads connected to the transmission line at tap nodes. The sending end and the receiving end each include a measuring device. The fault location is determined by obtaining measured circuit parameters including measured pre-fault and faulted current and voltage values at the sending end and at the receiving end of the transmission line. An equivalent tap node location is calculated using measured pre-fault and faulted current and voltage values at the sending end and at the receiving end of the transmission line. The equivalent tap node divides the transmission line into a sending side and a receiving side. The phase angle difference due to unsynchronized measurement using the measured pre-fault current and the measured pre-fault voltage values may be calculated. The equivalent load impedance of the tapped loads is calculated.

Abstract: A fault is located in a transmission line with a sending end, a receiving end, and a tapped load connected to the transmission line at a tap node. The tap node divides the transmission line into a sending side and a receiving side. The sending end and the receiving end each include a measuring device. The fault location is determined by obtaining measured circuit parameters including measured pre-fault and faulted current and voltage values at the sending end and at the receiving end of the transmission line. The phase angle difference due to unsynchronized measurement using the measured pre-fault current and the measured pre-fault voltage values may be calculated. The load impedance of the tapped load is calculated. A first fault location is calculated assuming that the fault is located on the sending side of the tap node. A second fault location is calculated assuming that the fault is located on the receiving side of the tap node.

Abstract: A method reducing transient overshoot of an output signal of an uninterruptable power supply, the uniterruptable power supply including: (a) an inverter having at least one power switch; (b) a digital controller that generates a pulse width modulated (PWM) signal for controlling the power switch, the PWM signal having a fixed period TPWM and (c) an analog to digital signal corresponding to the sampled output signal, the method comprising the steps of (1) operating the A/D converter to sample the output signal at a first time to generate a first sampled output value; (2) operating the A/D converter to sample the output signal at a second time to generate a second sampled output value, the period between the second time and the first time being equal to TPWM; (3) generating a control input value that is equal to 1.5 times the second sampled output value minus 0.

Abstract: A coaxial drop cable safety device is used for cable television, data and telephony applications. The device is used on buried drop cable where 60 Hz powering voltages applied to the drop cable exceed low voltage safety limits and where the drop cable is buried at depths which is less than the minimum required to meet electrical safety codes. Tap end and premise end units are connected to the drop cable. The tap end unit applies a DC voltage to the center conductor of the drop cable. A monitoring circuit in the tap end unit monitors the DC current in the center conductor. The tap unit will immediately remove the powering voltage in the event of either an open or faulted condition on the center conductor along the entire length of the drop cable. Additionally, while providing fault protection for the low frequency powering circuit due to tampering or damage to the cable, the fault monitoring circuit allows the high frequency television, data and telephony signals to pass with little or no impediment.

Abstract: A method of detecting systemic fault conditions in an intelligent electronic device is presented. The intelligent electronic device includes a microcontroller and associated memories. An algorithm (program) stored in a memory of the intelligent electronic device detects systemic fault conditions, i.e., root causes, as indicated by repeated, similar fault events.

Abstract: A method of operating a protective gear is described, in particular a remote protective gear for an electric power grid. In this method, a voltage signal is derived from the line voltage, and a current signal is derived from the line current. To guarantee reliable detection of a fault in the measurement circuit of protective gear, a voltage drop is gated with a current surge. A monitoring device provided for this purpose gates a first detection signal derived from the voltage signal for the voltage drop with a second detection signal derived from the current signal for the current surge. The monitoring function is suitable for both single-phase and multi-phase networks and permits a reliable differentiation between a network fault and a failure of the measuring circuit.

Abstract: An extremely low frequency (ELF) receiver that operates at the 6 Hz to 9 Hz range to synchronously receive signals from the electric (E) field or the magnetic (H) field of the earth's resonant (TS) frequency and other signals of interest.

Abstract: The digital protection system for a high voltage electricity network to instruct circuit breakers to open in the event of faults being detected by current and/or voltage sensors on the network lines connected to the circuit breakers includes a radio link for transmitting data with a mobile telephone of the “Bluetooth” type.

Abstract: A method or system consistent with this invention for detecting if a thyristor failed open in an alternating current input phase of a load comprises measuring an instantaneous power delivered to the load during a cycle of the input; determining a peak power delivered to the load during the cycle of the input; calculating an average power delivered to the load during the cycle of the input; and determining if the thyristor failed open by comparing the magnitudes of the peak power and the average power.

Abstract: Synchronous programs give increased sampling rates of AC signals and provide AC phasors yielding fast response to undesired conditions.

Abstract: This invention discloses an electronic hot-swap protection circuit for enabling hot swap connections and disconnections, the circuit includes a detector for detecting electrical current or voltage along a conductor which supplies power to a circuit to be protected during hot swap connections and disconnections, and a fast-disconnect, slow-reconnect switch connected in series with the detector and being operative in response to an output thereof, whereby the switch is relatively quickly opened when the absence of current is detected while the switch was closed and the switch is relatively slowly closed when voltage is detected following opening of the switch.

Abstract: A power supply controller having a multi-function terminal. In one embodiment, a power supply controller for switched mode power supply includes a drain terminal, a source terminal, a control terminal and a multi-function terminal. The multi-function terminal may be configured in a plurality of ways providing any one or some of a plurality of functions including on/off control, external current limit adjustments, under-voltage detection, over-voltage detection and maximum duty cycle adjustment. The operation of the multi-function terminal varies depending on whether a positive or negative current flows through the multi-function terminal. A short-circuit to ground from the multi-function terminal enables the power supply controller. A short-circuit to a supply voltage from the multi-function terminal disables the power supply controller. The current limit of an internal power switch of the power supply controller may be adjusted by externally setting a negative current from the multi-function terminal.

Abstract: A computer-implemented protection system is used in a multi-phase electrical distribution network. The system includes a sensor operable to measure an impedance of a device connected to a phase of the distribution network. The device improves coupling of electrical potential from a source to a load. The system also includes a processor connected to the sensor and programmed to receive an impedance measurement from the sensor. The processor automatically calculates a variation in impedance of the device, the variation being based on a ratio of the impedance measurement and a previous impedance measurement. The processor automatically performs a protection analysis of the device based on the impedance variation.

Abstract: A dishwasher having a cabinet and wash chambers in the form of drawers which slide in and out of the cabinet. Rigid and flexible closures are disclosed for sealing off the wash chambers when retracted into the cabinet. A detergent dispenser for the dishwasher is provided in one wall of a wash chamber in the wash water discharge path into the wash chamber so that detergent powder is flushed out of the dispenser and mixed with the wash water prior to the latter being discharged into the wash chamber. A wash programme for a dual wash chamber dishwasher is also disclosed which minimizes total water consumption by transferring water from one chamber to the other.

Abstract: A protection circuit of a diagnostic output line (K-line) of a control unit for protection of the control unit in the event of a ground disconnection or of a “below ground” condition is provided. The diagnostic output line includes a first interface DMOS transistor with a source connected to ground and a drain coupled to the diagnostic output line through a second DMOS transistor with a source connected to the output line and a drain connected to the source of the first DMOS transistor. The protection circuit also includes a comparator for the voltage of the diagnostic output line with the potential of the ground node, and a two-input logic gate, whose output controls a current generator forcing a current, limited by a resistor, on the diagnostic output line.

Abstract: An ESD protection circuit comprising a substrate having a first conductivity type, a well region having a second conductivity type, a first doping region having the first conductivity type, and a second doping region having the second conductivity type. The substrate is coupled to the reference potential, the well region is formed on the substrate and electrically coupled to the node, the first doping region is electrically floated on the surface of the well region, and the second doping region is disposed on the substrate and electrically coupled to the reference potential. Moreover, the electrostatic discharge current of the node provides a voltage with sufficient magnitude to breakdown the conjunction interface between the well region and the substrate, also triggering a BJT comprising the well region, substrate and the second doping region for dissipating the electrostatic discharge current.

Abstract: A system and method which detects and responds to abnormalities in a distribution system by reconfiguring nodes of the system to minimize the effects of the abnormality without the requirement of communicating with a central controller. The nodes in the system coordinate a response to a system abnormality through a process of self-organization in which each node acts based on its own programming, sensors, and stored data. Each node keeps other nodes apprised of its actions so that they may in turn decide what actions are appropriate for them to take.

Abstract: An apparatus and method is disclosed for retaining parameter information generated or received in an electronic circuit breaker (10). The electronic circuit breaker (10) includes a controller and is connected in a branch circuit coupled to a power source via a power line and powered by the power source. Upon occurence of a power fault, a control signal responsive to the power fault is generated and coupled to a control input of the circuit breaker. The control signal causes retention of parameter information generated or received in the electronic circuit breaker (10). Means for retaining the data representing parameter information include charging a storage capacitor to a predetermined value corresponding to the parameter information being retained, writing the parameter information being retained to an EEPROM and writing the data containing the parameter information being retained into a Static RAM.

Abstract: A power supply system for a sump pump including a transformerless inverter circuit with a plurality of MOSFET transistors for powering the pump using either available utility-supplied power or stored power from a battery.

Abstract: A protection circuit for a boost power converter provides input under-voltage protection and output over-voltage and over-current protection. The protection circuit includes a control power MOSFET connected in series between the ground of the boost power converter and the ground of the load. The arrangement of the circuit makes it easy to drive the gate of an N-channel power MOSFET and is ideal for current-limiting control, which utilizes the Rds-on of the MOSFET as a current sensing element. Neither a specific gate-driver nor a current sensing resistor is required, and thus high efficiency can be achieved. Furthermore, the slow slew-rate at the gate of the MOSFET provides a soft-start to the load. The protection circuit includes a temperature compensation circuitry to offset the variation of the Rds-on. A time delay circuit prevents the switching elements and protection elements from overload damage.

Abstract: A method for generating a signal identifying a three-pole short-circuit occurring in a three-phase power transmission line in which the phase currents and phase voltages are sampled forming phase current and phase voltage sampling values and the signal is formed from the phase current and phase voltage sampling values. In order to reliably detect three-phase short-circuits with such a method, even during oscillations, a positive phase-sequence system effective power parameter that is proportional to the instantaneous value of the positive phase-sequence system effective power of the power transmission line is formed, from which a grid frequency component parameter and a swing component parameter are then determined. The signal is generated from the grid frequency component parameter and the swing component parameter.

Abstract: A phase control switching system for controlling opening and closing timings of a power switching device to suppress the occurrence of an exciting rush current or a make-and-break surge voltage which is severe to system equipment such as a transformer, a reactor and a capacitor bank, or for controlling an arcing time of a circuit breaker to put the circuit breaker into operation for the arcing time leading to no-re-ignition or for the optimal breaking time. In the phase control switching system, a current measuring section or a current gradient measuring section is provided to measure a current value or a current gradient value of a current to be broken or introduced, and a reference phase detecting section estimates a current zero point of a current waveform on the basis of the measurements. Subsequently, a control section, upon receipt of an opening/closing command, an opening phase control operation using an arbitrary time point after the current waveform estimation as a reference.

Abstract: A voltage source provides an input signal to a drive circuit for a power semiconductor. A protective circuit is connected between the drain and the source of the power semiconductor and is activated when excess current is present. The protective circuit provides an output signal that is received by a control circuit to limit the voltage at the gate of the power semiconductor. The control circuit is connected between the gate and the source. A controllable resistance including an enhancement MOSFET and an external capacitor in which the enhancement MOSFET has a gate, a source and an internal capacitance between the gate and the source is connected in parallel to the external capacitance. The controllable resistance carries the input signal from the voltage source to the power semiconductor. The controllable resistance is switched to high impedance when the protective circuit is activated and switched to low impedance when the protective circuit is deactivated.

Abstract: An electrical connector includes an insulative housing retaining signal and power contacts therein. A resettable power regulation device is attached to the housing and electrically connected to the power contact whereby an excessive-power condition caused by an excessive-current or excessive-voltage power signal transmitted through the power contact triggers a shut-down operation of the regulation device thereby terminating transmission of the power signal to protect an electrical device connected to the connector. The resettable power regulation device resumes transmission when the power condition decreases to an operational level.

Abstract: A load driver circuit (10) includes an output driver (11) suitable for driving an inductive load (13). An output clamp circuit (15) clamps the output (12) to a high voltage during turn-off of the output driver (11). An open load detect circuit (26) clamps the output (12) to a lower voltage when the load (13) has an open circuit fault. A power fault voltage detect circuit (28) clamps the output (12) to another low voltage during a power fault condition.

Abstract: A load driver circuit (10) includes an output driver (11) suitable for driving an inductive load (13). An output clamp circuit (15) clamps the output (12) to a high voltage during turn-off of the output driver (11). An open load detect circuit (26) clamps the output (12) to a lower voltage when the load (13) has an open circuit fault. A power fault voltage detect circuit (28) clamps the output (12) to another low voltage during a power fault condition.

Abstract: A power supply circuit for supplying power to an output terminal includes an overcurrent decision circuit which determines whether an output current falls into an overcurrent range. A power supply controller stops the power supply supplying the power to the output terminal when the output current falls into the overcurrent range. A computer controls the power supply controller such that the power supply is started supplying the power to the output terminal when a cause of overcurrent is canceled.

Abstract: A system and method which detects and responds to abnormalities in a distribution system by reconfiguring nodes of the system to minimize the effects of the abnormality without the requirement of communicating with a central controller. The nodes in the system coordinate a response to a system abnormality through a process of self-organization in which each node acts based on its own programming, sensors, and stored data. Each node keeps other nodes apprised of its actions so that they may in turn decide what actions are appropriate for them to take.

Abstract: A current limiter is provided that includes a power switch for receiving input power from a power source and passing at least a portion of the input power to an output, a current sense mechanism coupled to the power switch for sensing current flowing through the current limiter and for providing a current flow signal related to the current flow through the current limiter, and a control mechanism coupled to the power switch that causes the power switch to reduce the current flow when the current flow signal indicates that the current flow exceeds a first current flow level. In one embodiment the current limiter may include a voltage sense mechanism that senses the voltage drop across the input to output of the device and use a reference voltage and a control loop to maintain the voltage drop relatively constant at all load currents.

Abstract: A short circuit protection circuit for IGBTs and similar power switch devices. Device collector voltage, e.g., desaturation voltage, is monitored to detect rapidly the occurrence of a short circuit fault. The voltage between the power device emitter and the Kelvin emitter terminals of the device preferably is also monitored and integrated to obtain an estimate of the current flowing through the power switch device. Circuit protection is implemented if either the measured collector to emitter voltage exceeds a selected level or the estimated current through the device exceeds a selected level. Upon the detection of the fault, a capacitor in parallel with a zener diode is connected between the power switch gate and ground. Thus, following a fault, the gate voltage is driven quickly to a low level as the voltage on the gate is discharged through the capacitor.

Abstract: A method is specified for operating a multiphase line which is included in a transmission network and can be disconnected if faults occur, for the transmission of electrical power. The method comprises the following method steps: a) detecting upstream and downstream of the line, data which characterize the operating status of the transmission network, b) processing the detected data in order to identify a fault, c) switching off at least one faulty phase of the line on the basis of the identified fault, and d) activating a balancing compensator which feeds compensation currents into the transmission network such that the currents flowing in the transmission networks form a balanced system. This method has the major advantage that, now, even lines subject to faults can be used for the transmission of electrical power.

Abstract: To improve operation reliability of a charge and discharge control circuit and a chargeable power supply unit using it, and to improve the life of secondary cell. In the charge and discharge control circuit of the chargeable power supply unit, the circuit surely keeps control operation during voltage of the cell falls down because of discharge current and, over-current state and over-discharge state occur at the same time.

Abstract: The safety device of industrial robot of the invention is intended to assure safety of the operator for teaching operation of an industrial robot.In the safety device of the industrial robot of the invention, a switch having two contacts working simultaneously is used as the dead-man's switch provided in the teaching pendant, and by monitoring the open or closed state of the two contacts working simultaneously, fusion of contact is judged by miss-matching of the opening and closing action, and the operation of the robot is stopped immediately. Besides, as an over-travel switch for actuating when the robot main body gets out of the normal moving range, a switch having two contacts working simultaneously is used, and by monitoring the open or closed state of the two contacts working simultaneously, fusion of contact is judged by miss-matching-of the opening and closing state, and the operation of the robot is stopped immediately.

Abstract: A rechargeable battery for a portable electric apparatus has at least one battery cell and a fuse device connected in series with the battery cell. Furthermore, the battery has a voltage-controlled active device, which is connected in parallel to the battery cell and which is arranged to assume a substantially non-conductive state and a conductive state, respectively, in response to the voltage at a control input, and a reference voltage device, which is connected to the control input of the active device. The active device is arranged to switch from the non-conductive state to the conductive state, when the voltage across the battery cell deviates, by a predetermined value, from a reference voltage supplied by the reference voltage device, thereby establishing a short circuit across the battery cell and release of the fuse device. The voltage-controlled active device, the reference voltage device and the fuse device form an integrated electronic component.

Abstract: Impedance protection method for detecting short-circuits on a monitored section of an electrical power supply line in which impedance values formed by current and voltage during a short-circuit in order to extract a tripping signal are checked to see whether they lie within a specific tripping characteristic. A relatively small first tripping characteristic in relation to the monitored section is used, and impedance values first determined are compared to this first tripping characteristic to see whether they lie inside or outside this tripping characteristic; the tripping signal is generated if the impedance values lie within the characteristic and, if not, the system switches to a maximum tripping characteristic corresponding to the monitored section. Impedance values following the impedance values first determined are checked to see whether they lie within the maximum tripping characteristic and, if they do, the tripping signal is generated.

Abstract: Problems associated with delta motors and motor controllers being subjected to increased motor torques and overcurrent conditions as well as with time consuming troubleshooting are eliminated in a motor controller that automatically inhibits operation of the delta motor when it detects common wiring errors that occur during the installation process.