Output control circuit for nuclear instrumentation device

The present invention provides an output control circuit which calibrates output signals from detectors of a nuclear instrumentation device of a PWR type power plant to a level of thermal power of a nuclear reactor. Namely, the output control circuit controls detection signals from a reactor. The output control circuit comprises a setting means for setting the amplification degree for controlling the output and a multiplying type D/A converter for multiplying the amplification degree set at the setting means and detection signals to be inputted and outputting them as a control output value. Then, when controlling an input signal level, it can be controlled by a simple constitution not using means such as CPU or S/W but using the multiplying type D/A converter. In addition, if the amplification degree is determined corresponding to the ratio between aimed output values and input signals, the amplification degree can be determined easily. (I.S.)