PHASE UNBALANCE ABB — Phase Imbalance Upstream
At a glance
- Severity
- WARNING
- Domain
- MV_SUBSTATION_SYSTEM
- Reference standard
- CEI 64-8
What it means
Current imbalance across phases upstream of final distribution: neutral and transformer overheating, loss of usable capacity.
Probable causes
- Single-phase loads concentrated on few phases in downstream boards
- Ungoverned load growth (servers, accessories)
- A failed branch shifting load onto the other phases
Where to start
Measure phase currents at the main board and sub-boards, locate where the imbalance originates and its trend in history.
Full guided diagnosis in the app
The diagnostic tree for this fault has 3 guided steps with measurements, checks and resolutions. You'll find it in DataCIQ, one of the five IndexOS apps: free, works offline.
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The same fault on other brands
More ABB codes
- 51 TRIP — LV Main Breaker Trip
- FEEDER TRIP — Loss of One MV Feeder
- MV BREAKER TRIP — Total MV Supply Loss
- SPD END OF LIFE — SPD Cartridges Depleted
- WTI TRIP — Transformer Overtemperature / Insulation Fault
- 2310 — Overcurrent Fault
- 2330 — Ground Fault
- 3210 — DC Bus Overvoltage Fault