What does error PCS-ARM-20 mean on a Felicity ESS?

PCS-ARM-20 means: ARM software fault - system underfrequency. Grid frequency too low.

Is error PCS-ARM-20 a fault or a warning?

PCS-ARM-20 is a fault code: the ESS unit enters protection and stops normal operation until it is cleared.

How do I clear or fix error PCS-ARM-20?

Reset to restart. Check whether grid frequency is beyond range of frequency protection action.

PCS-ARM-20

Felicity ESS error PCS-ARM-20

ARM software fault - system underfrequency

Fault — the ESS unit enters fault protection and stops normal operation until the fault is cleared — how it is shown (LED pattern or display code) depends on the model.

FLS-ES232LC-S

Energy storage systemFault

What it means

ARM software fault - system underfrequency

Cause: Grid frequency too low.

How to fix it

Reset to restart.
Check whether grid frequency is beyond range of frequency protection action.
Check for AC disconnection or islanding.

Source: FLS-ES232LC-S.pdf

Frequently asked questions

What does error PCS-ARM-20 mean on a Felicity ESS?: PCS-ARM-20 means: ARM software fault - system underfrequency. Grid frequency too low.
Is error PCS-ARM-20 a fault or a warning?: PCS-ARM-20 is a fault code: the ESS unit enters protection and stops normal operation until it is cleared.
How do I clear or fix error PCS-ARM-20?: Reset to restart. Check whether grid frequency is beyond range of frequency protection action.

Related error codes

Other codes on the FLS-ES232LC-S

All FLS-ES232LC-S codes

Prefer the full written guide? Read the complete Felicity inverter error-code guide

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