This app is in BETA testing, please report any bugs here.
ANSI Device Numbers
Quick search ANSI standard device numbers and their definition.
Ground Fault Protection Test
Electronic test form for documenting NEC required ground fault protection tests in accordance with NETA standards.
Instrument Transformer Test
Electronic test form for saving instrument transformer test data.
Loss of Excitation
Calculate useful values for testing GE & SEL generator protection relays.
Meter Settings Test
Electronic test form for saving multi-function metering tests.
Percent Error Calculator
Calculate percent error with calibrated and actual results.
Protective Relay Terms & Definitions
Over 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 Calculator
Calculate the protection trip time (TOC/IDMT) according to IEC 60255 and IEEE C37.112-1996 protection curves.

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