This practical guide shows you how to complete a signed, QR-verified UPS System Inspection certificate in OhmCert Module #09 and how to troubleshoot non-compliant readings on site.

1. Step-by-Step OhmCert UI Workflow

  1. Open Module #09: Navigate to UPS System Inspection 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 "400 kVA Data Center 2N UPS Module (Non-linear IT Load, 50 Hz)") to populate target limits automatically.
  3. Enter Your Field Measurements: Fill in the measured inputs (UPS Rating, Output Load, Measured Autonomy, Design Autonomy, Output Voltage Regulation Deviation, Output Voltage THD, Output Load Type, Static Bypass Transfer Time, System Frequency). Blank inputs stay neutral PENDING.
  4. Complete the 17-Point Checklist: Grade each item, attach photos if needed, and export the SHA-256 signed PDF certificate.

2. Worked Numerical Field Case Study

Scenario: 400 kVA Data Center 2N UPS Module (Non-linear IT Load, 50 Hz) (ANSI/TIA-942 2N) — Online double-conversion UPS feeding non-linear IT server load with 15 min design autonomy..

  • UPS Rating: 400 kVA
  • Output Load: 42 %
  • Design Autonomy: 15 min
  • Output Load Type: Non-linear (IEC reference load)
  • System Frequency: 50 Hz

3. Engineering Troubleshooting: Corrective Actions When a Reading Fails

  1. Rebalance single-corded or unequally loaded rack PDUs to keep each 2N UPS module below 45% normal load.
  2. Schedule battery string replacement when measured runtime falls below 90% of design autonomy (IEEE 1188).
  3. Check bypass synchronization slew-rate and phase window settings if static transfer exceeds 4-5 ms.

→ Try This Worked Example Live in Module #09 (UPS System)