Not all three-phase power systems are created equal — and the wrong setup can spell trouble for your VFDs. In this episode of VFD Vibes, host Greg Weichman sits down with application engineer Joe Pottebaum to unpack the world of power system configurations and their impact on variable frequency drive applications.

From the fundamentals of single-phase versus three-phase power to the nuances of wye, delta, corner-grounded, and high-resistance grounded systems, Greg and Joe cover the configurations you’re most likely to encounter in the field — and the implications each has for your installation. You’ll hear how these systems evolved, why grounding strategy matters, and what can go wrong if you don’t match your VFD to the supply.

Along the way, Joe shares field-tested advice on dealing with imbalanced systems, open-delta supplies, and ungrounded installations — plus how Yaskawa drives are built to handle real-world conditions that challenge other brands. Whether you’re an installer, engineer, or troubleshooting tech, this episode gives you the knowledge to spot risks before you press “Start.”

01:54 Single Phase vs. Three Phase Power
02:50 Applications of Single Phase Power
06:22 Three Phase Power in Industrial Settings
10:05 The Evolution of Three Phase Power
16:27 Grounding and Safety in Power Systems
25:06 Resistance Grounding and Line-to-Line vs. Line-to-Ground Faults
29:24 Challenges of High Resistance Grounding
32:14 System Grounding Standards
36:11 Impact of Ungrounded Systems
46:03 Delta vs. Wye Connected Systems
48:15 Yaskawa’s Solutions for Imbalanced Systems

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