AMT/AD-400 intelligent ammonia nitrogen sensor is a smart sensor using RS485 communication interface and standard Modbus protocol. Based on the coherent fluorescence detection technology, it has the advantages of good selectivity, strong anti-interference, high sensitivity, no pretreatment and fast measurement. Can measure chlorophyll, Rhodamine, etc. The PVC membrane based ammonium ion selective electrode is used to test the ammonium ion content in water, with temperature compensation to ensure that the test is fast, simple, accurate and economical.