This practical guide shows you how to complete a signed, QR-verified PDU / RPP Power Distribution & Phase Balance Audit certificate in OhmCert Module #21 and how to troubleshoot non-compliant readings on site.

1. Step-by-Step OhmCert UI Workflow

  1. Open Module #21: Navigate to PDU / RPP Power Distribution & Phase Balance Audit from the Dashboard.
  2. Load a 1-Click Standard Annex Preset: Open the blue Standard Annex banner at the top and click a preset (such as "250 kVA Data Center PDU (Balanced 3-Phase, K-13 Transformer)") to populate target limits automatically.
  3. Enter Your Field Measurements: Fill in the measured inputs (L1 Current, L2 Current, L3 Current, Neutral Current, Neutral Conductor Rating, Highest Continuous Branch Load, Branch Breaker Rating, Transformer K-Factor Rating). Blank inputs stay neutral PENDING.
  4. Complete the 14-Point Checklist: Grade each item, attach photos if needed, and export the SHA-256 signed PDF certificate.

2. Worked Numerical Field Case Study

Scenario: 250 kVA Data Center PDU (Balanced 3-Phase, K-13 Transformer) (ANSI/TIA-942) — Well-balanced 3-phase RPP feeding dual-corded server racks..

  • L1 Current: 185 A
  • L2 Current: 192 A
  • L3 Current: 181 A
  • Neutral Current: 48 A
  • Neutral Conductor Rating: 250 A
  • Highest Continuous Branch Load: 22 A
  • Branch Breaker Rating: 32 A
  • Transformer K-Factor Rating: 13

3. Engineering Troubleshooting: Corrective Actions When a Reading Fails

  1. Move single-phase rack whips between L1, L2, and L3 poles at the RPP schedule until phase current imbalance drops below 10%.
  2. Split overloaded racks onto new dedicated branch circuits so every continuous breaker stays <= 80% (and <= 40% per A/B path).
  3. Configure DCIM / BCMS warning alarms at 35% (dual-cord) / 70% (single-cord) and critical alarms at 40% / 80%.

→ Try This Worked Example Live in Module #21 (PDU / RPP Phase Balance)