A NERC ride-through standard reaches its first deadline on October 1, 2026. PRC-029-1 applies to inverter-based resources: solar, wind and battery storage. Bulk-system plants above 75 MVA must comply by that date; plants above 20 MVA connected above 60 kV follow by January 1, 2027.
Loads are not covered by PRC-029-1. They have their own rules, and those moved faster. ERCOT’s NOGRR282 took effect August 1, 2026 for computational loads of 75 megawatts and more. FERC has ordered national standards for the same class of load by the end of the year.
The pattern is one rule per side of the meter, with the same physics under both. Stay connected through the disturbance, and show evidence that you can. Most operators have never measured their own sensitivity. That measurement is the place to start.
We explain the generation standard and the load rule on the Data Centers and Compute page, and the tolerance envelopes at SEMI F47 and the ITIC curve.
A regulated supply draws more current as the voltage falls
Each server in a data hall draws through a switching power supply with power factor correction. A regulated supply holds its output power. At its input, current equals power divided by voltage, so lower voltage means more current. That extra current deepens the drop across the wires and transformers feeding the supplies. The Data Centers and Compute page works through the arithmetic.
ERCOT wrote NOGRR282 around the same arithmetic. Between 80% and 50% voltage, a large computational load is allowed to reduce its consumption in proportion to voltage. The rule also reaches into the facility’s own protection. Facility schemes count sags, typically three in one minute, and transfer to backup until reset. NOGRR282 now prohibits sag-counting trip schemes for sags the load must ride through.
The equipment curves answer a different question
SEMI F47 and the ITI curve set what equipment must survive. The Standards Compliance page lists their points. The July 2024 faults recorded on the Data Centers page fell inside the region NOGRR282 now requires a large computational load to ride through. The same faults fell outside the ITI and SEMI F47 envelopes, where equipment carries no obligation to function.
The evidence starts with a record at the site. NOGRR282 requires a root cause report within 90 days of a ride-through failure on ERCOT’s request. The Resilience page sets out the measurement: a week of Class A logging, with the sag count read against the equipment’s own curve.
Where this stands today
The Data Centers and Compute page now carries both rules. It records that PRC-029-1 sets ride-through for inverter-based generation from October 1, 2026, and does not apply to loads. For loads, it sets out the voltage bands that NOGRR282 requires a large computational load to ride through.
The Standards Compliance page states that our controller does not provide ride-through. In a sag inside its band, the controller corrects the load current. Both pages close on the same first step, one week of measurement at the site.
Related reading
- Voltage Stability: the voltage at a panel as a symptom of the current
- Request a site analysis: the facts an engineer reads before saying what to measure first
