The purpose of this standard is to define the requirements for demonstrating acceptable performance of safety system instrument channels through response time testing, calibration verification, and other means. The same requirements may be adopted for demonstrating the acceptable performance of non-safety systems and other instrument channels. This Standard contains the main topics in its body and includes annexes to provide further information. The annexes are for information only and contain a selection of the available methods.
The methods described in this are used to check instrument calibration for accuracy and time response. It covers direct methods used to set calibration within required tolerances and indirect methods to indicate a need for a direct calibration. The use of the indirect methods allows for longer periods between the routine direct calibrations.
This international standard describes test methods for ensuring that safety system instrument channels in nuclear power plants comply with specifications for accuracy, response time and other performance characteristics.
BS IEC 62385 applies to those instruments whose primary sensors measure temperature, pressure, differential pressure, liquid level, flow and neutron flux. The standard focuses on the test methods that can be used remotely while the plant is on-line without a need to enter the reactor containment or physically access the instruments.