What does error 0x2153 mean on a Felicity ESS?

0x2153 means: Communication loss between SBCU and EMS (for liquid-cooled single cabinet). No signal received or life signal unchanged.

Is error 0x2153 a fault or a warning?

0x2153 is a fault code: the ESS unit enters protection and stops normal operation until it is cleared.

0x2153

Communication loss between SBCU and EMS (for liquid-cooled single cabinet)

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

Energy storage systemCritical

Communication loss between SBCU and EMS (for liquid-cooled single cabinet)

Cause: No signal received or life signal unchanged.

Send faults to EMS, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay.

Source: FLS-ES232LC-S.pdf

What does error 0x2153 mean on a Felicity ESS?: 0x2153 means: Communication loss between SBCU and EMS (for liquid-cooled single cabinet). No signal received or life signal unchanged.
Is error 0x2153 a fault or a warning?: 0x2153 is a fault code: the ESS unit enters protection and stops normal operation until it is cleared.
How do I clear or fix error 0x2153?: Send faults to EMS, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay.

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