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error Upgraded

Error Code Solid Red

LED indicator showing solid red — fault condition detected: Over current, low DC voltage, or operating temperature below 0°C.

? What Causes This

One of three fault conditions: (1) Current exceeds 45A, (2) Battery voltage below 9V for 12V systems or 18V for 24V systems, or (3) Operating temperature below 0°C.

How to Fix It

  1. Check which specific fault is indicated by reviewing the LCD display.
  2. If over current: disconnect solar array and check for shorts.
  3. If low voltage: charge battery or check connections.
  4. If low temperature: move unit to warmer location above 0°C.
  5. See specific fault codes (OC, CPF04, CPF09) for detailed remedies.

Source: page 34 of the official manual

From the manual

Manual page 34 — Upgraded error Solid Red

This error code appears in:

Upgraded 30A Solar Charge Controller