Siemens SIMATIC IPC547D Operating Instructions Manual page 75

Procedure
1. Unlatch the fan rack on the heat sink and remove it.
2. Remove the highlighted fan connector.
3. Remove the highlighted screws.
4. Remove the heat sink.
5. Unlock the socket and lift the socket cover.
SIMATIC IPC547D
Operating Instructions, 06/2011, A5E03473780-01
The fourth screw is hidden by the heat sink in the figure.
Device maintenance and repair
7.1 Removing and installing hardware components
75