Instructions
Go to the Netflix website using your web browser and log on to your user account.
Click the "Your Account and Help" link at the top right-hand corner of the window.
Click the "Manage Netflix ready devices and computers" link under the "Watching Instantly on Your TV or Computer" heading. A list of registered streaming devices will appear.
Find the PS3 console on the list of devices and click "Deactivate" in the right column. A confirmation dialog box will appear.
Click "Yes" to confirm deactivation. Your PS3 now has been removed from the Netflix user account.