Siemens SIMATIC ET 200SP HA Equipment Manual page 18

Terminal
5.3 Schematic circuit diagram
Firmware update
The supply voltage L+ must be available on the I/O module at the start of firmware updates and
during the update.
Redundantly working modules with product version less than 3
A firmware update during operation is not permitted for redundantly working "DI 16×NAMUR
HA" modules with product version less than 3.
Reason:
A wire break can result in incorrect process values during the update.
18
WARNING
Equipment Manual, 08/2019, A5E39293880-AD
DI 16xNAMUR HA