Real-Time Measurements

Presentation

TS trip system perform the following real-time tasks:

• Measure the following currents in real time and as an RMS value:

  • Current for each phase and the neutral (if present)

  • Ground-fault current

• Determine the maximum values for these electrical quantities

• Calculate the current unbalances

The values of the electrical quantities, whether measured or calculated in real time, update once a second at rated frequency.

Measurement Availability

Measurement data is available on the EcoStruxure Power Device app through NFC wireless communication.

Measuring the Neutral Current

4-pole circuit breakers or 3-pole circuit breakers with the ENCT wired and configured measure the neutral current:

• For a 3-pole circuit breaker, the neutral current is measured by adding a current transformer on the neutral conductor.

• For a 4-pole circuit breaker, the neutral current is measured systematically.

The neutral current is measured in the same way as the phase currents.

Measuring the Ground-Fault Current

The ground-fault current is calculated or measured in the same way as the phase currents, according to the circuit breaker configuration, as shown in the following table.

Measuring the Current Unbalances

TS trip system calculate the current unbalance for each phase (three values).

The current unbalance is a percentage of the average current:

Maximum Values

The TS trip system determines the maximum (MAX) value reached by the following electrical quantities for the period from the last reset to the present time:

• Phase and neutral currents

• Ground fault current