NETA ETT Level 3 study guide
NETA ETT Level 3 · Work through your exam, one topic at a time.
The NETA ETT Level 3 credential - the Electrical Testing Technician Level III - is a tiered certification for field technicians who commission, maintain, and troubleshoot power systems. Level 3 signals that a technician can work independently on complex apparatus, interpret test results against standards, and make field decisions without close supervision. The NETA ETT Level 3 study guide has 10 sections and about 2,575 words.
01Electrical Safety and Safe Work Practices
This domain tests how you establish and verify an electrically safe work condition, select PPE and test instruments, and apply NFPA 70E and OSHA rules in the field. De-energize, lock/tag, release stored energy, and verify absence of voltage before work.
284 words, about 1 min02Codes, Standards, and Reference Documents
This domain tests which document governs a test, how the NEC sets minimum installation rules, and how NETA ATS/ATO and IEEE standards define test methods and intervals. NFPA 70 (NEC) is installation code; NETA ATS covers acceptance testing; NETA ATO covers maintenance testing; IEEE standards give test methods and interpretation.
242 words, about 1 min03Test Equipment and Measurement Fundamentals
This domain tests accuracy, resolution, burden, calibration, and safe connection of meters and test sets. Accuracy is stated as % of reading or % of full scale; a 1% full-scale meter on a 500 V range has +/-5 V error even at low readings.
245 words, about 1 min04Insulation Resistance and Polarization Index Testing
This domain tests IEEE 43 methods: selecting DC test voltage, connecting guard, correcting for temperature, and interpreting IR, DAR, and PI. Select test voltage by winding rating: commonly 500 V DC for under 1000 V, 500-1000 V for 1000-2500 V, and higher voltages for medium-voltage apparatus; never exceed the winding rating.
268 words, about 1 min05Winding Resistance and Low-Resistance Measurement
This domain tests DC resistance measurement of transformer, motor, and switchgear current paths using stable current, four-wire connections, and temperature correction. Inject a stable DC current and measure the voltage drop; R = V/I.
248 words, about 1 min06Transformer and Reactor Testing
This domain tests turns ratio, polarity, excitation, winding resistance, insulation, impedance, oil, and sweep frequency response, plus reactor resistance and inductance checks. Turns-ratio deviation is typically limited to +/-0.5% of nameplate or adjacent phases; check all taps and compare phase-to-phase.
232 words, about 1 min07Circuit Breaker and Switchgear Testing
This domain tests contact resistance, insulation, overpotential, timing, travel, trip/close coils, minimum pickup, and interlocks on breakers and switchgear. Contact resistance is a micro-ohm measurement; compare phases and previous data.
254 words, about 1 min08Protective Relays and Instrument Transformers
This domain tests secondary injection of relays, CT and VT ratio/polarity/burden, pickup and dropout, timing, and trip-circuit verification. CT polarity: P1 enters, S1 leaves; verify with a DC kick or polarity test.
252 words, about 1 min09Cables, Grounding Systems, and Ground-Fault Protection
This domain tests cable insulation and fault-location tests, grounding electrode and grid measurements, soil resistivity, and GFCI/GFP operation. Cable insulation tests include IR, DC or VLF withstand, tan delta, and partial discharge; use the test voltage and duration specified for the cable type and age.
284 words, about 1 min10Rotating Machinery and Motor Testing
This domain tests insulation resistance/PI, winding resistance balance, surge comparison, hipot, vibration, and motor circuit evaluation. Test IR/PI per IEEE 43: record at 1 and 10 minutes, correct for temperature, and discharge after testing.
266 words, about 1 min