The nuclear instrumentation system provides maximum reliability and
safety, yet minimizes erroneous readings or signals from the monitoring
channels. This is done by using two or more measuring channels in each
operating range, and then interlocking the circuits so that at least two
of them give the same signal of abnormal operating conditions before
initiating a reactor “scram.”
Increased reliability is obtained by using “solid state” instruments or
magnetic amplifier units rather than electron tubes and relays.