Phase Converters & Power Factor
Phase Converter Efficiency
Installing a Phase Converter
Rotary Phase Converters
Static Phase Converters
VFDs as Phase Converters
     • Harmonic Distortion
Three-Phase Motors
Phase Converters & Voltage Balance
Phase Converter Applications
     • Submersible Pumps
     • Woodworking Equipment
     • Dual Lift Stations
     • Phase Converters & Welders
     • Phase Converters & CNC Machines
     • Phase Converters & Air Compressors
     • Phase Converters & Elevators
     • Phase Converters & Wire EDM
     Phase Converters & HVAC
Phase Converters & Transformers
     • Step-up Transformers
     • Buck-Boost Transformers
     • Isolation Transformers
Phase Converter Experts
Digital Phase Converters
Regenerative Power
Three-Phase Power
     • Delta vs. Wye Configured Power
Motor Starting Currents

Phase Converters and Wire EDM


Wire EDM equipment is used to machine metal and other materials by electrostatic discharge.  The equipment does not utilize motors except for coolant pumps, but rather the main use of electrical power in the equipment is a rectifier that converts the utility supplied AC power to DC.

Similar to three-phase motors, it is best to operate three-phase rectifiers with balanced three-phase power.

Operating with unbalanced voltages can lead to damage of some of the rectifier components, especially at full load, and severe imbalance will increase the ripple current on the capacitors of the DC bus. Too much ripple current can lead to damage of these capacitors.

A static converter must never be used to operate a wire EDM.  It will lead to damage of the machine.

A phase converting VFD must never be used to power a wire EDM because it contains electronics, thus capacitive loads.  The PWM voltage of a VFD will damage these

electronics. Rotary converters can be used with wire EDM, but the shortcomings of these converters affect rectifier systems in much the same way motor systems are affected. The variable amperage demand from the EDM will result in voltage imbalance from the rotary converter, leading to possible damage to the equipment or variable cutting performance.

Digital phase converters can safely and efficiently operate EDM equipment because they produce balanced voltage under variable load conditions and produce sine wave voltage safe for operating solid state electronics.