NETA ETT Level 1 case studies
NETA ETT Level 1 · Put your knowledge to work in context.
The NETA ETT Level 1 credential (Electrical Testing Technician Level 1, administered by the InterNational Electrical Testing Association) is an entry-tier certification for technicians who test, inspect, and commission power systems. It is aimed at people building a career in field acceptance and maintenance testing: technicians new to the trade, electricians moving into testing, and students in electrical power programs. The exam samples the practical knowledge a beginning tester needs across safety and hazard awareness, test instrument selection and care, insulation resistance and polarization index testing, low- and high-voltage circuit breaker testing, protective relays and instrument transformers, transformer ratio and winding resistance work, grounding and ground-fault protection, cable/switch/motor circuit testing, and interpreting standards while producing defensible test records. Expect multiple-choice items that lean on field judgment rather than memorized trivia: which instrument, which connection, which limit, which safety step comes first. The NETA ETT Level 1 case studies are 5 cases and about 2,475 words.
1Backfed MCC Bucket and Insufficient Arc-Rated PPE
At a wastewater plant, a 480Y/277 V double-ended MCC feeds a 75 hp VFD bucket from bus A. The owner locked open main breaker A and applied a lock and tag, but the tie breaker between the two sections is closed, so bus A is backfed from source B.
501 words, about 3 min2VFD Measurement with Wrong Meter and Megger Connection
A maintenance crew is troubleshooting a 480 V, 125 hp VFD driving a 156 A motor. The drive runs at 4 kHz carrier frequency.
538 words, about 3 min3Low Polarization Index on a 4.16 kV Motor After Heaters Were Off
A 4.16 kV, 2000 hp form-wound motor is on a scheduled outage. The winding temperature is 40 °C and the ambient humidity is 78%.
495 words, about 2 min4Vacuum Breaker Contact Resistance Imbalance
During an annual outage, a 15 kV, 1200 A, 25 kA vacuum circuit breaker is overhauled. The breaker has stored-energy spring operators and was last tested three years ago.
491 words, about 2 min5CT Ratio Mismatch Discovered During Primary Injection
On a 13.8 kV feeder, the phase overcurrent relay is fed by a 600:5 multi-ratio CT. The settings engineer calculated pickup and time dial using a 600:5 ratio.
450 words, about 2 min