New Zealand South Island (EIPC cl 8.25A) ride-through requirements

Low-voltage ride-through for New Zealand. Every breakpoint below is read from the code itself, and where a point was taken off a published figure rather than stated in the clause, the section under that chart says so — an envelope that stops where its published chart stops.

1Envelope
LVRTEvents
Transmission Connection level
LVRT

What is the low-voltage ride-through envelope for New Zealand South Island (EIPC cl 8.25A)?

The plant must ride through for any voltage that stays on or above this envelope. The envelope holds 0 pu from t = 0 to 140 ms; then ramps linearly from 0.14 pu at 140 ms to 0.35 pu at 500 ms; then 0.76 pu from 500 ms to 3 s; then 0.9 pu from 3 s, plotted to 6 s.

The clause states this boundary as a line; intermediate points are interpolated between its stated vertices. The envelope stops where the published chart stops; the code states no end time.

Applies to Grid-connected generating stations, South Island (Fig 8.2)

New Zealand South Island (EIPC cl 8.25A) — low-voltage ride-through envelopeNew Zealand South Island (EIPC cl 8.25A) low-voltage ride-through envelope. The plant must ride through for any voltage that stays on or above the line; below it, the envelope no longer applies. Logarithmic time axis from 0.01 s to 10 s; linear voltage axis in per-unit. The first band applies from the instant of the event (t = 0). The envelope holds 0 pu from t = 0 to 140 ms; then ramps linearly from 0.14 pu at 140 ms to 0.35 pu at 500 ms; then 0.76 pu from 500 ms to 3 s; then 0.9 pu from 3 s, plotted to 6 s. Stops where the published chart stops — the code states no end time.New Zealand South Island (EIPC cl 8.25A) — low-voltage ride-through envelopeStops where the published chart stops — the code states no end timenominal 1.00 pu0.010.11100.000.200.400.600.801.001.20Time from event start (s, log scale) · first band applies from t = 0Voltage (pu)0.9 puplotted to 6 sMUST RIDE THROUGHmust ride through on or above the lineends at the plotted window, not a stated limit
Low-voltage ride-through envelope for New Zealand South Island (EIPC cl 8.25A). Time runs on a logarithmic axis, so the ramp — a straight line in real time — only looks curved here. Scroll the chart sideways for the rest of the time axis →
Low-voltage ride-through breakpoints for New Zealand South Island (EIPC cl 8.25A)
From To Voltage Between the points
0 140 ms 0 pu Held flat
140 ms 500 ms 0.14 → 0.35 pu Ramps linearly
500 ms 3 s 0.76 pu Held flat
3 s plotted to 6 s 0.9 pu Held flat
The clause this came from

Electricity Industry Participation Code 2010, Part 8, cl 8.25A(1) and (6), Figure 8.2 — verified in the 1 May 2025 consolidation; clause unchanged at 1 July 2026. The code defines a linear recovery ramp; the vertices are read from the clause and the chart draws the segment between them.

Scope

Who does New Zealand South Island (EIPC cl 8.25A) bind, and since when?

Grid-connected generating stations, South Island (Fig 8.2). No date of effect is published here — grid codes are reissued, so check the current issue before relying on it.

These figures are a reading aid, not legal advice. Grid codes are reissued: verify against the current edition before you design to them.

Digitised operating parameters beyond ride-through — droop, reactive capability, operating ranges — are published for 36 of the 66 codes in this atlas, not yet for New Zealand South Island (EIPC cl 8.25A). That is a gap on this site, not a statement that New Zealand South Island (EIPC cl 8.25A) sets none — the atlas hub marks the codes that carry them.

Curve data last checked against the code on — 66 standards, 130 envelopes, published by bess.engineer under CC BY 4.0.

Questions

Questions this page answers about New Zealand South Island (EIPC cl 8.25A)

Does New Zealand South Island (EIPC cl 8.25A) require ride-through, or only that the plant does not trip?
Ride-through. Every envelope on this page is a performance duty the plant must meet, not a protection-setting no-trip boundary — they are different obligations. That is what these curves are; they are not everything New Zealand South Island (EIPC cl 8.25A) contains. The requirement sentence under each chart says which side of the curve is the compliant one.
Are the numbers on this page taken from New Zealand South Island (EIPC cl 8.25A) itself?
Every breakpoint is read from the code, and where a point was taken off a published figure rather than stated in the clause, the section under that chart says so — on this page that includes an envelope that stops where its published chart stops. The clause each curve came from is quoted under it.
Which events are charted for New Zealand South Island (EIPC cl 8.25A)?
New Zealand South Island (EIPC cl 8.25A) is charted here with 1 envelope — low-voltage ride-through (LVRT). No high-voltage or frequency envelope is charted here — check New Zealand South Island (EIPC cl 8.25A) itself before concluding it sets none.
Related

Ride-through, in context.

An envelope is a compliance boundary; understanding why it exists is a different question. The ride-through and grid-forming entries cover the engineering, and the Engineering Foundations course builds it from the physics up.

Also for New Zealand: New Zealand (EIPC cl 8.25A), New Zealand North Island (EIPC cl 8.19(1)), New Zealand North Island (EIPC cl 8.25A)

Elsewhere in Asia-Pacific: Philippines PV (PGC 2016 Fig 4.4), Philippines VRE (PGC 2016 Tables 4.1 & 4.3), Philippines Wind (PGC 2016 Fig 4.2), and 9 more