Study Of Measuring Technology For Drum Water-level In Boiler And PLC Appliance In Water-Level-Protection

Drum water-level is the important parameter of the boiler. It influences the operating reliability and economics of the boiler. This paper puts forward a more accurate engineering calculating way for difference-pressure type water-level instruments and the innovative optimizing advice using multi-scale rule for assembling the local connected-pipes type water-level instruments and the electrode type water-level instruments, measuring the existing problems to the boiler drum water level of thermal power plant after the document [No. 2001791]dilivered by national power corporation," 《Some Prescript About Configure, Installation And Employ Drum Water-Level Instruments System In Power Stations By national power corporation 》 " ,via studying the measurement characteristic to various instruments.This problems described as: The transformation is concentrated to the difference pigeonholing type steam dome fluviograph, Fluviograph and electric contact fluviograph remain stationary basically on the spot, all kinds of steam dome of water levels measure the deviation of the device in operating not only reduced , and increase in various degrees, particularly outstanding under the circumstances that load change the old operating mode; Steam dome both sides store water level in measure the deviation in various degree. On the basis of solving problem of measuring, this paper introduces a whole set of schemes of a PLC appliance realizing calculation for difference-pressure type water-level instruments and water-level protection system. this scheme has implemented and made the good result in Hunan Jinzhushan power plant.