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AC Voltage CalculatorConvert between peak, peak-to-peak, rms, and average AC voltage quantities.
AI Chat BotBETA Module. TestGuy GPT Open AI model trained on electrical testing and engineering topics.
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 & DefinitionsQuick 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.
Circuit Breaker Terms & DefinitionsDynamic quick reference of over 150 circuit breaker terms and acronyms.
Contact Resistance DBCompare contact-resistance to real world values submitted by TestGuy members.
DGA Diagnosis, Duval's TriangleBETA Module. Diagnose transformer fault types using dissolved gas values and Duval's triangle.
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 Fault Protection TestElectronic test form for documenting NEC required ground fault protection tests in accordance with NETA standards.
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.
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.
Protective Relay Terms & DefinitionsOver 200 protective relay terms and definitions, compiled from the Institute of Electrical and Electronics Engineers and the National Association of Relay Manufacturers.
Relay TOC/IDMT CalculatorCalculate the protection trip time (TOC/IDMT) according to IEC 60255 and IEEE C37.112-1996 protection curves.
Study GuideFind useful study resources, organized in accordance with ANSI/NETA ETT certification standards.
Switchgear TestElectronic form for testing switchgear equipment in accordance with NETA standards.
Tech QuizSharpen your skills with our collection of quizzes on electrical safety, maintenance & testing of electrical equipment and industry standards.
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.
Transformer Terms & DefinitionsQuick reference of over 125 transformer terms and acronyms with dynamic search.
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.
Webinar AgendaStay up to date with the latest industry trends and best practices with these free upcoming webinars! Expand your knowledge and earn potential CTDs from the comfort of your workstation.
Wire Size CalculatorCalculate the appropriate low-voltage wire size based on NEC Article 310.15.
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