利用常规仪器(堆控制室中的启动装置)测得反应堆中稳定的中子计数率来刻度控制棒的反应性当量。我们把这个试验方法称为计数率法。此法简单方便,适合运行班使用。此法已在若干次重要实验中应用,保证了反应堆的启动和实验的安全.本文对原理公式作了推导,并对空间效应和应用中的若干问题进行了讨论。 The steady-state neutron count rate in the reactor was measured using conventional instrumentation (starter in stack control room) to scale the reactive equivalent of the rod. We call this test method count rate method. This method is simple and convenient, suitable for operating classes. This method has been applied in several important experiments to ensure the start-up of the reactor and the safety of the experiment.This paper deduces the principle formula and discusses some problems in the space effect and its application.