These four markets share fast growth and new standards but differ completely in detail, so one document set does not cover all four.
1. India IS 18968:2025
India replaces THD with TRD (total rated-current distortion) limited to 5% Irated, the easiest difference to miss. Ride-through is classified into Categories I, II and III, with III the most demanding; during mandatory operation, Categories II and III may not reduce apparent current below 80% of the pre-disturbance value. At least one of IEEE 2030.5, DNP3 and SunSpec Modbus is required. The national annex changes the default connection delay (60 s) and the synchronisation voltage step (5%).
2. Korea KS C 8565:2024
Korea specifies two values per voltage/frequency band: operating time and separation time, for example 70%-90% V: run 1.5 s, separate 2.0 s; V above 120%: separate 0.16 s. Anti-islanding must disconnect within 0.5 s and reconnection must be blocked for more than 5 minutes. Configuring timers directly from Tables 3 and 4 is faster than tuning by experience.
3. Brazil ANEEL PRODIST Module 3
Brazil is the friendliest for micro inverters: up to 75 kW, redundant protection is not required if the inverter already includes the protections in Table 1; 75-500 kW adds directional overcurrent. RoCoF cuts both ways: as a protection setting it must exceed 2.0 Hz/s with more than 100 ms delay, while the unit must tolerate 1.0 Hz/s. That high/low combination is a Brazil-specific trap.
4. South Africa NRS 097-2-1:2024
South Africa requires a safety disconnect unit (SDU): two series electromechanical switches per current-carrying conductor including neutral for inverters without simple isolation. Synchronisation requires 60 s of stable voltage and frequency, islanding must stop supply within 2 s, and DC injection above threshold must open the SDU within 500 ms. These are structural requirements, so confirm at selection stage.
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