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Ansi Device Numbers

Quick search ANSI standard device numbers and their definition.

Trip Unit TCC Calculator

Generate test currents and generic trip times for LSIG trip units, includes tolerance for pickup and time values.

Electrical Symbols

Browse common electrical symbols or search dynamically by name.

Insulation Resistance Values

Correct insulation resistance (IR) test results to 20°C or 40°C and lookup recommended values.

Metric Unit Converter

Convert between common test values such as Mega to Kilo and Base to Micro

Motor Calculations

Find FLA for electric motors or convert between Horsepower and Watts

Breaker MVA Calculator

Find MVA rating of a circuit breaker using nameplate ratings.

Ohm's Law Calculator

Calculate the relationship between voltage, current, and resistance or the relationship between power, voltage, and current.

Percent Error Calculator

Calculate percent error with calibrated and actual results.

Power Factor Calulations

Calculate power factor for single- and three-phase circuits and find correction capacitor.

Power Triangle Calculator

Find PF, VAR, W and VA with any two known quantities or review power triangle formulas.

Relay Trip Curves IEC/IEEE

Calculate the protection trip time (TOC/IDMT) according to IEC 60255 and IEEE C37.112-1996 protection curves.

Relay Loss of Excitation

Calculate useful values for testing GE & SEL generator protection relays.

Terms and Definitions

A complete library of terms related to electrical testing, with dynamic search.

Bolt Torque Values

Look up the recommended torque value for various types and grades of U.S. standard fasteners.

Transformer Calculations

Get recommended test values, find TTR and load currents for single- and three-phase transformers.

Voltage Drop Calculator

Estimate the voltage drop of an electric circuit based on the wire size, distance, and anticipated load current.

Wire Size Calculator

Calculate the appropriate low-voltage wire size based on NEC Article 310.15

Tech Quiz

Distraction free testing environment.

My Progress

Review past exam scores and get stats on your progression.

Fall of Potential

Electronic form for saving fall of potential test data.

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