LIVE · VOLTAGE
National voltage (per-unit)
Measured transformer-terminal voltage across the monitored network, normalised to per-unit against each asset's nominal level and averaged — a defensible national voltage index. See tiers & regions for the breakdown, or transformer taps for how hard the fleet is working to hold it.
Mean voltage
— pu
Lowest
— pu
Highest
— pu
Points monitored
—
National voltage (per-unit) over time
Shaded band = ±6% (the 11 kV / 33 kV statutory limit); the dashed line is nominal (1.00 pu). Higher-voltage tiers have a wider ±10% statutory band.
How this is built (and what it isn't)
- Measured, then per-unit. Each reading is the actual terminal voltage at a transformer; we divide by the nearest GB nominal level (11/22/33/66/132/275/400 kV) to get per-unit, so tiers combine on one dimensionless scale.
- National = mean of per-unit across every monitored point in the latest window ("sum and divide"). It is a monitored-network proxy, not a full-GB figure.
- Coverage: —
- Tap: reported as activity (operation counts), never position — no live tap position exists in the source data.