Accelerator complexes rely on multiple sensors to be able to reach desired operational conditions, including safety. For example, Beam Loss Monitor sensors are used for both machine safety, and to help operators steer the beams. These critical devices are installed periodically along the beam lines, and as an example, over 3500 of these sensors are installed in CERN's Large Hadron Collider. To ensure their smooth and safe operation, the sensor performance should be validated before each run. In the last long shutdown at CERN, part of this validation was undertaken using a robotic system for the first time. The system consisted of a 9DOF arm mounted on the Train Inspection Monorail robot, that removed a radioactive source from shielding installed on the robot, before bringing it closer to the sensor, triggering the ionisation chamber, and checking the results were correctly generated. The operations have been remotely operated via tele-manipulation, and in the future, developments will focus on autotomizing part of the measurements under supervised control and checks of remote operators. This work presents the operation and the modular software framework that has been developed to manage this validation campaign and robotic mission.