Motor Feeder Calculator
Estimate multi-motor feeder current from entered motor currents and a largest-motor factor for qualified review.
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Motor FLA, running current, starting current, horsepower, torque, overload, and starter sizing calculators.
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Motor Circuit Conductor Size Calculator
Estimate an entered motor conductor ampacity reference and compare it with selected ampacity for qualified review.
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Motor Branch Circuit Protection Calculator
Estimate an entered motor protection reference and compare it with a selected rating for qualified review.
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VFD Volts-per-Hertz Calculator
Calculate a VFD base volts-per-hertz reference from motor nameplate voltage and frequency using the specified drive manual.
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VFD DC Bus Voltage Calculator
Compare expected and measured VFD DC bus voltage and express recorded ripple as a percentage.
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VFD Dynamic Braking Resistor Calculator
Calculate braking energy, peak resistor power, average duty power, and minimum resistance from entered inertia and speed change.
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Motor Synchronous Speed Calculator
Calculate rotating-field speed as a reference for induction-motor slip. The result does not predict loaded rotor speed or select equipment.
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Motor Slip Frequency Calculator
Express motor slip as frequency for a motor or drive review. The result does not diagnose a motor or tune a drive.
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Motor Load Percentage Calculator
Review motor loading from measured input power or a documented electrical-power estimate. The calculation does not infer load from current alone.
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Motor Current Unbalance Calculator
Review a recorded three-phase motor current set during maintenance or commissioning. The result does not diagnose the motor or choose a repair.
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VFD Sizing Calculator
Compares required VFD output current with an entered drive rating using motor FLA, application multiplier, derating factor, and system voltage.
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NEMA Code Letter Calculator
Estimates kVA per horsepower and the matching NEMA-style code-letter range from horsepower, voltage, phase, and locked-rotor current.
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Motor Torque Calculator (hp or kW to lb-ft and N-m)
Convert motor horsepower or kilowatts and rpm into shaft torque in lb-ft and N-m.
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Motor Voltage Drop Calculator
Estimates running and starting voltage drop and remaining motor voltage from current, one-way length, conductor resistance, system voltage, and phase model.
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Motor Overload Calculator
Compares a motor overload setting from nameplate FLA and an entered percentage with a recorded device setting, with motor load shown in kVA.
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Motor Slip Calculator
Estimates induction-motor slip as a speed difference in rpm and as a percentage of synchronous speed from measured rotor speed.
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Motor Disconnect Size Calculator
Compares a motor disconnect current basis with an entered disconnect rating using motor FLA, multiplier, voltage, and phase.
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Motor Efficiency Calculator
Estimates ideal motor efficiency and power loss from electrical input power and mechanical output power.
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Locked Rotor Current Calculator
Estimates motor locked-rotor current from full-load current and a selected multiplier, with an optional comparison against a starting-current reference.
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Motor Starter Current Reference Calculator
Estimate starting current, overload reference current, and starter continuous-current discussion values from motor FLA and entered project assumptions.
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Motor Starting Current Calculator
Estimate motor starting current from full-load current and a selected starting multiplier, with a voltage-sag reference for preliminary review.
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Motor Power From Current Calculator
Estimate motor input power, output power, and horsepower from line current, voltage, phase model, power factor, and efficiency.
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Motor Current Calculator
Estimate motor running current from horsepower and operating assumptions for preliminary load, voltage-drop, and feeder review.
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Full-Load Current Estimate Calculator
Estimate motor full-load current from horsepower, voltage, phase count, efficiency, and power factor before verified nameplate or table review.
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