Regional Basic Professional Training Course in Korea

Regional Basic Professional Training Course (BPTC) on Nuclear Safety
part (hafnium). When the reactor is operating, these rods are arranged as follows:
Two safety rods in the up position.
Three shim rods and a regulating rod.
The control rods placed in the core are controlled by mechanisms located in a room under
the pool. They are controlled by shafts that pass through the bottom of the pool.
The reactor has two operating modes:
An operating regime with a maximum power level of 1.4 MW in which the core is
cooled by natural convection of the water in the pool.
A nominal or intermediate power operating regime for which the core is cooled by
forced convection using the primary coolant system pumps (three pumps in service
and one in reserve).
These two operating regimes are covered in the control system by the low and high power
regimes:
Low power regime (from the sub‐critical state to 1.4 MW)
Three identical start‐up systems (known as low‐level systems) with mobile detectors
(fission chambers) are used to determine the power of the reactor from the position of the
counter and its count rate. When the thresholds associated with the neutron parameters of
the core (thresholds established at 1.1 MW and 1.4 MW) are exceeded, the regulating
rods automatically stop rising and the safety rods drop.
High power regime (up to rated power +10%)
Two operating modes are associated with the high power regime:
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