Is error 0x20B3 a fault or a warning?

0x20B3 is a fault code: the ESS unit enters protection and stops normal operation until it is cleared.

How do I clear or fix error 0x20B3?

Send faults externally, cluster disables insulation detection function with high voltage prohibited. Recovers on normal sampling.

0x20B3

Battery cluster SBCU internal bus voltage sampling fault (before applying high voltage)

Critical — the ESS unit shuts down and latches a protection fault. Don't keep restarting it — the cause needs checking first.

Energy storage systemCritical

Battery cluster SBCU internal bus voltage sampling fault (before applying high voltage)

Cause: Invalid internal bus voltage sampling.

Send faults externally, cluster disables insulation detection function with high voltage prohibited.
Recovers on normal sampling.

Source: FLS-ES232LC-S.pdf

What does error 0x20B3 mean on a Felicity ESS?: 0x20B3 means: Battery cluster SBCU internal bus voltage sampling fault (before applying high voltage). Invalid internal bus voltage sampling.
Is error 0x20B3 a fault or a warning?: 0x20B3 is a fault code: the ESS unit enters protection and stops normal operation until it is cleared.
How do I clear or fix error 0x20B3?: Send faults externally, cluster disables insulation detection function with high voltage prohibited. Recovers on normal sampling.

Compiled from official Felicity user manuals. Always consult your device manual and a qualified technician before performing repairs.