Grid surge

Inverter manuals state their surge withstand for surge category B as standard waveform peak values: 6 kV/0.50 kA for the ring wave and 6 kV/3 kA for the combination wave. When a grid surge is suspected, read the surge protection device's records first. Its surge logs can be viewed and show the recorded events. Some surge protection devices count low-level surges. A sensitivity threshold that can be adjusted locally or over Modbus decides which surges are counted. Some string inverters have a built-in test of the AC surge protection device. It is disabled by default under the IEEE 1547, Rule 21 and ISO-NE grid codes, so confirm it is enabled before relying on it. On some inverters a type 2 surge arrester protects the AC side, alongside the grid monitoring function.

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• sentence 1: support check: partial - The table gives category B values of 6 kV/0.50 kA (ring) and 6 kV/3 kA (combination), but the passages don't say that inverter manuals state them as the surge withstand.
• sentence 2: support check: partial - The passages only show a table-of-contents entry for viewing surge logs; they don't say to read the SPD records first or what the logs show.
• sentence 3: support check: partial - A sensitivity threshold for the valid low surge count is adjustable on the local display and over Modbus, but the passages never say it decides which surges are counted beyond the threshold description.
• sentence 4: support check: partial - The AC SPD test parameter defaults to Disable under all three grid codes, but the passages don't say the test is built into string inverters or tell the reader to confirm it is enabled.
• sentence 1: review: partial - The category B ring-wave (6 kV/0.50 kA) and combination-wave (6 kV/3 kA) peak values are stated under Surge Suppression, but the passages never call them the inverter's surge withstand.
• sentence 4: review: partial - Both CPS parameter rows show an AC SPD test that defaults to Disable under IEEE 1547, Rule 21 and ISO-NE, but the advice to confirm it is enabled before relying on it is not in the passages. -->