SET-FK-2D Split-Phase Intelligent Composite Switch, 20-40 kVAR

Split Phase Composite Switch SET-FK-2D

Independent phase switching for 220V capacitor steps, combining zero-crossing thyristor control with low-loss latching-relay conduction.

Request a Model Recommendation

Designed for unbalanced low-voltage loads

SET-FK-2D allows capacitor compensation to be controlled by phase, making it suitable for distribution systems where single-phase loads create unequal reactive-power demand. Each phase channel follows the command from a compatible compensation controller instead of forcing all three phases to switch as one step.

The hybrid switching path controls the transient electronically and then transfers steady conduction to a latching relay. This reduces capacitor inrush, avoids switching arc and minimizes heat during continuous operation.

Correct each phase independently

Capacitor steps can respond to different reactive-power demand on phases A, B and C.

Reduce unnecessary switching

Only the phase that requires compensation is switched, avoiding over-compensation on lighter phases.

Improve low-voltage balance

More precise reactive-power control supports better phase loading and power-factor management.

Zero-voltage closing

The switch searches for the optimum waveform point before connecting a capacitor channel, limiting the switching transient.

Zero-current opening

Disconnection occurs around the current zero crossing, reducing arcing and stress on the switching path.

Low steady-state loss

The latching relay carries continuous current after the electronic switching interval, controlling cabinet heat.

Compact multi-channel device

Three phase channels, control input and status indicators are integrated in one 110mm-wide module.

🏢 Commercial distribution
Office floors, shopping areas and mixed single-phase tenant loads.

🏘️ Residential complexes
Phase-by-phase compensation in low-voltage distribution rooms.

💡 Lighting systems
Compensation where phase loading changes independently.

🏭 Mixed factory loads
Panels combining three-phase equipment with substantial single-phase demand.

When should I use SET-FK-2D instead of SET-FK-3D?

Choose SET-FK-2D when capacitor steps must be switched independently by phase in an AC 220V split-phase compensation system. For common three-phase AC 380V capacitor steps, use the SET-FK-3D series.

What controller output is required?

The source manual specifies a DC 5-12V / 12mA control signal. Confirm the controller output and terminal assignment before wiring the switch into the compensation panel.

Why combine a thyristor with a latching relay?

The electronic stage manages the switching transient at the optimum waveform point, while the relay carries steady current with low loss. This supports smooth capacitor switching and helps limit cabinet heat.