Wire classification: two-wire system: both ends of the thermal resistance of the connecting leads the way to a wire resistance of the signal is called the two-wire: This wire is simple, but because of the connecting wires must exist Communicator lead resistance r MCT404, r size and length of the wire material factors relating to, so this method is applicable only lead to less accurate measurement occasions; three-wire: Connect one end of the lead in the thermal resistance of the base and the other end connected to the two leads the way called three-wire, in this way usually associated with supporting the use of the bridge, it can better eliminate the effects of lead resistance, industrial process control most commonly used; four-wire system: the root ends of the thermal resistance of the connecting two wire four-wire system is called, where the two leads provide a constant current I is thermal resistance, the R into a voltage signal U, and then through the other two lead the U lead to the second instrument. This approach can be seen completely eliminate lead wire resistance influence MCT404, it is mainly used for high-precision temperature detection. RTD three-wire connection. Three-wire connection to eliminate measurement errors caused by lead resistance. This is because the measurement of thermal resistance of the circuit is generally unbalanced bridge. Thermal resistance as a bridge arm resistance of the bridge, connecting wires (from the thermal resistance to the control room) has become part of the original MCT404 bridge arm resistance, and this resistance is unknown and part with the ambient temperature changes, resulting in a measurement error. Three-wire, the wire connected to a power supply terminal bridge Honeywell MCT404 Communicator, the remaining two are located respectively to the thermal resistance of the arm and the adjacent bridge arm, thus eliminating wire line Resistance to bring measurement error. Many different types of transmitters, in general, is a signal emitted by the transmitter to the secondary instrument secondary instrument display the measured data. The physical measuring signal is converted to a standard or common electrical signal output or device capable of communication protocol mode output. Generally divided into: temperature / humidity transmitter, pressure transmitter, differential pressure transmitters, level transmitters, current transmitter, power transmitter, flow transmitter, weight transmitters. MCT404 Communicator _MCT404_ Hua Hui science and technology provided by the Jinan-Technology Co., Ltd. Jinan Huahui Technology Co., Ltd. (www.cnhuahui.com/) strong, credible, in Jinan, Shandong pressure instrumentation industry has accumulated a large number of loyal customers. The company better work attitude and constantly improving innovative ideas will lead China-Technology into the brilliant and you work for a better future!