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.
Battery InspectionElectronic form for testing battery systems in accordance with NETA standards.
Battery Terms & DefnitionsQuick reference of over 250 battery terms and acronyms with dynamic search.
Bolt Torque ValuesLook up the recommended torque value for various types and grades of U.S. standard fasteners.
Contact Resistance DBCompare contact-resistance to real world values submitted by TestGuy members.
Digitrip GF PickupsFind expected Ground Fault pickup values for most Cutler-Hammer/Westinghouse Digitrip RMS trip units.
Disconnect Switch TestElectronic form for testing most types of disconnect and loadbreak switches in accordance with NETA standards.
Electrical SymbolsBrowse common electrical diagram symbols or search dynamically by name.
Fall of Potential TestElectronic test form for saving fall of potential test data.
General InspectionElectronic test form for saving notes during general inspections.
Ground Resistance/Continuity TestElectronic test form for saving point-to-point ground resistance test data.
Instrument Transformer TestElectronic test form for saving instrument transformer test data.
Insulation Resistance TestElectronic test form for saving insulation resistance test data.
Loss of ExcitationCalculate useful values for testing GE & SEL generator protection relays.
Low-Voltage Circuit Breaker TestElectronic form for testing low-voltage power circuit breakers in accordance with NETA standards.
MV Cable Test VoltageGet recommended voltage for DC and VLF cable testing.
MV Cable VLF/TD TestElectronic form for VLF/TD testing medium-voltage cable in accordance with NETA standards.
MVA CalculatorFind MVA rating of a circuit breaker using nameplate ratings.
Maintenance FrequencyGet recommended service intervals for power distribution equipment and build maintenance plans.
Meter Settings TestElectronic test form for saving multi-function metering tests.
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.
Polarization Index TestElectronic test form for saving polarization index (PI) test data.
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.
Switchgear TestElectronic form for testing switchgear equipment in accordance with NETA standards.
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.
Temperature Correction FactorsCorrect insulation resistance (IR) test results to 20°C or 40°C and lookup recommended values.
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.
Thermography (IR) ToolsGet action levels, convert temperature, and more tools for infrared scanning.
Transformer ConfigurationsGet recommended test values, TTR tolerance and load currents for most ANSI transformers.
Trip Unit TCC CalculatorGenerate test currents and generic trip times for LSIG trip units, includes tolerance for pickup and time values.
Two-Winding Transformer TestElectronic form for testing dry-type and liquid-filled transformers with TTR, WR, and PI.
Vacuum Circuit Breaker TestElectronic form for testing medium-voltage vacuum circuit breakers in accordance with NETA standards.
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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