Battery undervoltage

Battery undervoltage means the battery voltage seen by a battery inverter or hybrid inverter has fallen too low, and the device raises an error or warning. On Sunny Island it shows as F213, or as F922 and W938 when the battery management reports it over SiCom. Hybrid inverters may show a battery undervoltage message. Measure the battery voltage at the inverter connection point first, and check that it is within the battery's specified range. On Sunny Island, a reading below 39 V means the battery is deeply discharged. Recharge it straight away with emergency charge mode or an external charger, then give it a manual equalization charge. If the voltage is above 39 V but the Sunny Island will not restart, the inverter itself should be replaced. If it does restart, review the battery protection settings so the battery is not drained that far again. Use a load-shedding contactor to drop DC loads when the state of charge is low, which helps prevent repeat events. On SMA Home Storage, a cell undervoltage fault makes the red LED on the battery module flash quickly. Low PV generation in winter can leave the battery rarely cycled and lead to undervoltage, so newer firmware recharges the battery from the grid. If a cell undervoltage fault persists after restarting the battery and inverter, contact the battery manufacturer or service.

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• sentence 2: support check: partial - F922 and W938 via SiCom and a generic undervoltage message are supported, but the F213 row is labeled 'Warning low battery voltage' and the hybrid inverter statement is vague; mapping of F213 is supported loosely.
• sentence 6: support check: partial - Load-shedding contactor for DC loads at low SOC is stated, but the 'prevents repeat events' purpose is not explicitly stated.
• sentence 1: review: partial - Battery voltage too low raising an error or message is supported by the F213 and Solis rows, but no passage text says the Solis device is a 'hybrid inverter'. -->