The invention relates to a four-
electrode testing device and a measuring method for the
water content of tobacco. The
water content of the tobacco is reflected by measuring the resistance of the tobacco through four electrodes as probes according to the
specific function relationship between the resistance and the
water content. The four-
electrode testing device is formed in a way that a range selector is respectively connected with an
electrode A, an electrode B, an electrode C and an electrode D through a singlechip computer and a resistance measuring circuit, and a PC (
Personal Computer) is connected with a
liquid crystal display circuit through a data uploading circuit and the singlechip computer. Compared with an
infrared ray moisture meter, the four-electrode testing device disclosed by the invention has the characteristic that the measured result of the water content of the tobacco is prior to the precision and the efficiency of the
infrared ray moisture meter. The influence from electrode polarization caused by measurement of single
voltage through a pair of electrodes and the influence from offset
voltage caused by measurement through single-direction power supply of the electrodes are overcome, so that the precision is increased; and the deviation of zone selection during measurement of a pair of electrodes is overcome, and thus the credibility of the measurement result is improved. A detection circuit is simple, the requirements on the color, shape and specification of the materials and light of a measurement environment are lower, the measurement result can be obtained more quickly and the water content inside the materials can be measured.