Siemens SENTRON 3WA1 Manual page 145

Fail-safe firmware update
The update process of the 3WA air circuit breaker is executed in a fail-safe manner. A
failed or aborted firmware update cannot render any device unusable.
The firmware update can be executed again at any time.
Note
Firmware versions of individual modules
If you wish to update the BSS200 Breaker Status Sensor and the digital input/output
module IOM230 to a firmware version higher than 2.0.0, the modules must have at least
firmware version 2.0.0. An update to a version higher than 2.0.0 is not possible directly
from firmware version 1.x.x.
Example:
Current firmware version: 1.0.0 > Update to firmware version 2.0.0 > Update to firmware
version 2.1.0
Update of the ETU600 electronic trip unit
The ETU600 has two processors. A processor (protection processor) is responsible for
protecting the circuit breaker. This has been tested during production (routine test
according to IEC 60947-2) and can no longer be changed by a firmware update.
The second processor (application processor) is responsible for the functions that are
not relevant to protection. The application processor of the ETU600 electronic trip unit
can be updated to the latest version via a firmware update. The firmware update is
executed in a fail-safe manner.
The protection processor continues to be active during the firmware update of the
ETU600. As a result, the 3WA air circuit breaker never loses its protective function during
the firmware update.
3WA1 air circuit breaker
Equipment Manual, 02/2023, 92310000002-06
2.8 Communication and system connection
Description
143