Abstract Based on analysis of the advantages and shortcomes of different charge level indicators a ZL-I type intelligent charge level indicator has been designed in account of the power plant conditions. This indicator can be used to measure not only the level in coal and pulverized coal bunkers and in fly ash silos
but also the hight of coal piles in coal yards. Such indicator can also find its application in metallugical
chemical and cement works and mines to measure the charge level or the hight of piles made up of particulate material.