Regional Basic Professional Training Course in Korea

Regional Basic Professional Training Course (BPTC) on Nuclear Safety
For the reactor control, the power signal used is that of the control system, fitted with a
non‐compensated ionisation chamber. The low‐level, high‐level systems and the control
system are re‐calibrated periodically by means of heat balance, carried out on the water in
the primary coolant system, and by measuring the activity due to nitrogen‐16 in the
primary coolant system water.
The instrumentation and control system was renovated in 1993. A programmed protection
system is used for the acquisition and processing of neutronic and thermal hydraulic
measurements as well as the generation of shutdown commands using logic safety
systems (2 out of 3 votes). The emergency shutdown commands cut off the power supply
to the electromagnets holding the safety rods, causing them to drop under the effect of
gravity.
4.2.3.3. Core structure
The core structure is located at the centre of the bottom of the pool. It consists of a
vertical pipe with a rectangular cross‐section that includes, from bottom to top:
A water inlet casing.
The core housing.
A water outlet casing.
A duct.
A diagram of the core structure is presented in Figure 4.1.
The core cooling water comes in through the inlet casing, moves upwards through the
core and goes out through the output casing. On the one hand, the direction of the core
cooling water requires that all the elements contained in the core be secured to prevent
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