Siemens SINUMERIK 840D sl Function Manual page 562

Commissioning
10.7 Replacing a motor or encoder
After at least one of these encoder components has been replaced, Alarm 27035 "Axis %1
new HW component, acknowledgment and function test required" is output (changed CRC in
index 1 of $MA_SAFE_ACT_CHECKSUM[ ] and possibly Alarm F01680 with ID 2, i.e.
hardware IDs have changed).
When replacing motors with integrated encoders, Alarm F01680 "SI Motion CU: Checksum
error safe monitoring functions" is output with fault value 2 (changed CRC of parameter
p9728[2]), i.e. changed hardware identifiers). Also in this case, an acknowledgment is required
and a function test must be performed.
The term "function test" designates a partial acceptance test that is described in detail in the
alarm description.
If Alarm 27035 or F01680 with ID 2 is output, a new softkey "Acknowledge SI HW" is displayed
in the alarm screen. This can only be actually selected with key switch setting 3 (the same as
for the user agreement).
Figure 10-16
The following message is displayed after pressing softkey "Ackn. HW":
562
Acknowledging SI HW
Function Manual, 12/2017, 6FC5397-4BP40-6BA1
Safety Integrated