Siemens SINUMERIK 840Dsl Configuration Manual page 25

Installation
The "Sample Applications" additionally install a service with the name "OPC UA Local
Discovery Server". If you want to locally test the OPC UA connection, i.e. an installation directly
on the PCU 50, you must deactivate this service.
Note
If the service "OPC UA Local Discovery Server" is active, the SINUMERIK OPC UA server
cannot be started correctly, because it blocks the needed TCP port 4840.
This service has no influence if the "Sample Applications" are installed on a PC in the network.
Deactivation is then not necessary.
Figure 3-4
SINUMERIK Integrate for Engineering Access MyMachine / OPC UA
Configuration Manual, 04/2018, 6FC5397-1DP41-0BA0
Deactivating the "OPC UA Local Discovery Server" service on PCU 50
Setting up of OPC UA server
3.5 Testing the connection
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