Phase sequence detector

  
This circuit prevents damage to the load due to incorrect phasing. The three power SSR's are only permitted to turn-on for a phase sequence of phase A leading phase B. If phase A lags phase the input currents will cancel, causing the SCR and the inhibit SSR to remain off until the sequence is reversed.
Phase sequence detector  - schematic

The inhibit SSR is included to maintain isolation at the input.



News


    .