Breaker Size Calculator
Apply an entered continuous-load factor to a load schedule and compare the adjusted current with a selected breaker rating without choosing a device automatically.
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Insulation resistance, short-circuit current, pull-box sizing, grounding, bonding, touch voltage, and protection checks.
Published Calculators
Arc Flash Study Scenario Comparison Calculator
Compare compatible arc-flash study records by method, units, source, and numerical difference.
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Available Fault Current Calculator
Calculate available fault current from transformer kVA, secondary voltage, phase, impedance, and an entered source multiplier.
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Arc Flash Input Data Completeness Calculator
Measure completeness of an entered arc-flash study input list without calculating incident energy.
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Arc Flash Boundary Calculator
Compare a documented arc-flash distance with an entered distance and report signed and absolute differences.
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Approach Boundary Worksheet Calculator
Compare two documented approach-distance records after unit conversion and report the signed difference.
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Three-Phase Voltage Unbalance Calculator
Calculate three-phase voltage unbalance from measured line-to-line readings and an entered reference.
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Transformer Winding Resistance Temperature Calculator
Normalize transformer winding resistance to a reference temperature for comparison of documented test readings.
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Transformer Turns-Ratio Test Calculator
Compare measured transformer turns ratio with an expected nameplate ratio by tap or test point.
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Motor Winding Resistance Imbalance Calculator
Compare three measured motor phase-winding resistances as a preliminary test record before qualified interpretation.
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Earth Electrode Test Calculator
Summarize earth-electrode test readings, resistance spread, calculated resistance, and comparison margin for qualified field review.
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CT Ratio Test Calculator
Calculate expected and measured current-transformer ratios from nameplate and test readings, then compare the deviation with an entered review reference.
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Polarization Index Calculator
Estimates the 10-minute-to-1-minute insulation-resistance ratio and compares it with an entered reference PI. The result is a comparison calculator, not an acceptance decision.
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Grounding Resistance Calculator
Estimates single-rod and combined grounding resistance from soil resistivity, rod geometry, rod count, and spacing. The result is a model calculation, not a field test.
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Continuity Test Calculator
Correct a continuity-test resistance reading for entered lead resistance and compare it with a reference threshold; test current is recorded for context only.
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Short-Circuit Current Calculator
Estimate available fault current from source voltage and total impedance on a common equivalent-circuit basis, with an optional screening multiplier for preliminary review.
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Pull Box Sizing Calculator
Estimate preliminary pull-box dimension references from the largest raceway and same-wall raceway sum before verifying NEC 314.28 and the installed layout.
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Insulation Resistance Calculator
Calculate a temperature-corrected insulation-resistance worksheet value and compare it with an entered screening reference.
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