Abstract:This paper discusses the matrix switch module,operational amplifier,A/D converter and processing module connected in series to realize the automatic identification and exchange method of positive and negative poles of multiple thermocouple sensor signals from each measuring device.This method abandons the original backward method that traditional various types of instrument wiring must distinguish positive and negative polarity.Wiring will no longer artificially distinguish positive and negative polarity.Back-end instruments will automatically detect positive and negative polarity.After discovering that the polarity of a measuring device is reversed,the polarity is automatically physically exchanged and then connected to the amplifier for rear processing.Actual measurement verifies that this method greatly reduces the workload of on-site wiring and checking polarity,and greatly simplifies the on-site installation work.