400V · 63A to 1000A · Custom-Built to Your Requirements · Professional Enclosure
For three-phase inverters and phase-sensitive equipment, the live grid phases must arrive in the correct sequence (R→Y→B). When Eskom or your local grid authority carries out maintenance, they sometimes reconnect phases in the wrong order — causing your inverter or protected appliance to shut down and refuse grid power.
This can be corrected manually by swapping wires at the DB, but if it happens repeatedly you're paying electrician callout fees every time. The Automatic 3-Phase Sequence Corrector detects the incoming sequence continuously and switches internally to always present the correct R-Y-B order to your load — with no manual intervention required.
Monitoring relay continuously reads incoming phase sequence
Compares incoming sequence against correct R-Y-B order
Contactors re-route phases automatically in <100ms
Correct R-Y-B sequence delivered to your equipment
Any equipment that is sensitive to phase sequence — or that uses phase rotation to determine motor direction — will benefit from this unit. Below are the most common applications:
Prevents inverter shutdown when Eskom reverses phase sequence during maintenance.
Prevents motors from running in reverse due to incorrect incoming phase order.
Protects borehole, irrigation and industrial pumps from reverse rotation damage.
Prevents compressor trips and reverse-rotation damage on large HVAC systems.
Keeps UPS on grid power — avoids battery drain during phase reversals.
Protects CNC machines, compressors and manufacturing equipment from sequence faults.
Protect all three-phase loads across an entire building from a single board installation.
Ideal for farms using three-phase pumps and irrigation systems on Eskom supply.
The main three-phase isolator must be switched off and locked out before any work begins. A qualified electrician must verify with a voltage tester.
The unit is wall-mounted near your main DB or inline with the supply to the equipment being protected. Ensure adequate ventilation.
The three incoming phases (R, Y, B) and neutral are connected to the input terminals of the corrector board.
The output terminals feed your inverter, motor or distribution board. The corrected R-Y-B sequence is always present at the output.
Supply is restored and the unit is tested by deliberately swapping input phases to verify automatic correction is working correctly.