5. Measurement operation

5.1 Flow chart concepts

The flux map is the result of the measurements made by the mobile internal instrumentation system when scanning the 60 assemblies selected for this purpose, i.e. a three-dimensional power distribution over the core.

Executing or recording a flux map therefore consists in performing the eleven passes (ten normal passes plus one intercalibration pass) required to explore the 60 assemblies with the six fission probes. If necessary, the backup procedure can be used.

There are two types of flow maps:

• complete flow maps, which explore all 60 assemblies;

• partial flow maps, during which a reduced number of assemblies are explored....