There was one fault that caused more than 2 hours downtime during period 47.
There was a problem with the oil tank level sensor which did not work properly. As the oil level is fundamental to the system, the sensor is hardwired to stop the telescope control system. This causes the whole systems to fail, and repeated tries to restart the system caused a variety of error message. The sensor value itself is not linked to the control system, so it was not so easy to define where the precise error occurred. The system has been changed such that any future failure will be detected as an alarm from the sensor. As the oil level was correct, the sensor was first by-passed, and later the sensor was cleaned and the wiring checked. After some time the sensor failed again it has now been replaced with a new one.