TeqNexus | Electrical Testing Calculator

PT / VT Ratio & Injection

Primary Voltage (V)

Secondary Voltage (V)

Applied Primary Injection (V)

Measured Secondary (V)

Nominal ratio = Vprimary / Vsecondary. Expected secondary = Injection / ratio. Ratio error = (Measured − Expected) / Expected × 100.

CT Ratio, Secondary & Injection

CT Primary Rating (A)

CT Secondary Rating (A)

Primary Test Current (A)

Measured Secondary (A)

Relay CT Secondary Input (A)

Relay Test Current (× In)

Expected CT secondary = Primary test current × CT secondary / CT primary. Relay injection current = CT secondary input × selected multiple.

Relay Pickup / FLC / Setting

Load / Motor Rating (kW)

Voltage (V)

Power Factor

Efficiency (%)

CT Primary (A)

CT Secondary (A)

Pickup Setting (% of CT Primary)

3-phase FLC ≈ kW×1000 / (√3×V×PF×η). Primary pickup = FLC × setting %. Relay secondary pickup = primary pickup × CT secondary / CT primary.

Transformer Full Load Current

Transformer Rating (kVA)

HV Voltage (V)

LV Voltage (V)

Phases

Transformer Differential Reference

Transformer MVA

HV Voltage (kV)

LV Voltage (kV)

HV CT Ratio (Primary/5A)

LV CT Ratio (Primary/5A)

Differential Pickup (%)

For 3-phase transformer current: I = MVA×1000/(√3×kV). This tool gives reference currents; actual differential compensation depends on relay vector group, CT connections and relay configuration.

Hi-Pot Test Voltage Reference

Equipment Rated Voltage (kV)

Multiplier / Test Factor

This is only a calculation reference. Actual AC/DC withstand voltage and duration must be taken from the applicable standard, manufacturer test specification and site procedure.

Load / Power Calculator

Voltage (V)

Current (A)

Power Factor

Phases

Relay Time Calculator & Test Guide

Select protection and enter settings. The calculator shows pickup, 2×, 5× and 10× injection, angle guidance, theoretical operating time and test purpose.

Protection Function

OMICRON Protection Test Plan

Select the protection and enter the relay/transformer data. The tool generates a clear test-plan table showing injection current, angle, purpose and expected result. Final angles/compensation must be checked against the exact relay model, vector-group implementation and approved test procedure.