One of the many reasons why points can go to a {fault} condition, relates to the R1 firmware revision of the Siemens N 148/22 KNXnet/IP Interface device. It may also occur with other KNXnet/IP Interface devices.
The problem is caused by the KNXnet/IP Interface device failing to respond with an Acknowledge message although message confirmation has been requested by the KNXnet/IP driver.
You may also observe that the Fault Cause property of the Point Proxy Extension indicates Read fault: confirmation — Confirm Timed Out.
One way to overcome this problem is to upgrade the R1 firmware revision level of the Siemens N 148/22 KNXnet/IP Interface device (or any other KNXnet/IP Interface device) . However, it is beyond the scope of this document to detail the steps to accomplish this but it is believed that manufacturers of KNXnet/IP Interface devices do provide tools and guidance to upgrade their firmware.
Another way to overcome the problem, is available within the KNXnet/IP driver. To do this, the KNXnet/IP driver must be configured not to request an acknowledgement to its messages. This can be configured by using a hidden property in the Tunnel Connection of the KNXnet/IP driver. (see Knx Device/Comms Connections/Tunnel Conn).
Unhide the requestAcknowledgements slot of the Knx Network / Knx Device / Comms Connections / Tunnel Conn.
Change the Request Acknowledgements property to false.