AC Voltage CalculatorConvert between peak, peak-to-peak, rms, and average AC voltage quantities.
Ansi Device NumbersQuick search ANSI standard device numbers and their definition.
Bolt Torque ValuesLook up the recommended torque value for various types and grades of U.S. standard fasteners.
Breaker MVA CalculatorFind MVA rating of a circuit breaker using nameplate ratings.
Digitrip GF PickupsFind expected Ground Fault pickup values for most Digitrip RMS trip units.
Electrical SymbolsBrowse common electrical diagram symbols or search dynamically by name.
Fall of PotentialElectronic form for saving fall of potential test data.
Insulation Resistance ValuesCorrect insulation resistance (IR) test results to 20°C or 40°C and lookup recommended values.
Loss of ExcitationCalculate useful values for testing GE & SEL generator protection relays.
Maintenance FrequencyGet recommended maintenance service intervals for power distribution equipment.
Motor CalculationsFind FLA and torque for electric motors or convert between Horsepower and Watts.
My ProgressReview past exam scores and get stats on your progression.
Ohm's Law CalculatorCalculate the relationship between voltage, current, and resistance or the relationship between power, voltage, and current.
Percent Error CalculatorCalculate percent error with calibrated and actual results.
Power Factor CalulationsCalculate power factor for single- and three-phase circuits and find correction capacitor.
Power Triangle CalculatorFind PF, VAR, W and VA with any two known quantities or review power triangle formulas.
TOC/IDMT CalculatorCalculate the protection trip time (TOC/IDMT) according to IEC 60255 and IEEE C37.112-1996 protection curves.
Tech QuizDistraction free testing environment.
Terms and DefinitionsA complete library of terms related to electrical testing, with dynamic search.
Test Unit ConverterConvert between common test values such as Mega to Kilo and Base to Micro.
Transformer CalculationsGet recommended test values, find TTR and load currents for single- and three-phase transformers.
Trip Unit TCC CalculatorGenerate test currents and generic trip times for LSIG trip units, includes tolerance for pickup and time values.
Voltage Drop CalculatorEstimate the voltage drop of an electric circuit based on the wire size, distance, and anticipated load current.
Wire Size CalculatorCalculate the appropriate low-voltage wire size based on NEC Article 310.15.
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