Siemens SIMATIC NET SFP Operating Instructions Manual page 23

6. Remove the sealing plug of the plug-in transceiver.
7. Insert the connecting cable into the pluggable transceiver until you hear it engage.
The connecting cable is then firmly secured.
Transceiver SFP/SFP+/SCP/STP
Operating Instructions, 10/2023, A5E02630804-18
4.5 Using a pluggable transceiver (SCP/STP)
Assembling
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