Temperature is one of the most important thermal parameters at the telecommunication room. Temperature control of precision would have a significant impact to the equipment. Temperature control mode is diverse, and PLC is high reliability, which is easy to learn and use, use of PLC is one of the comparative advantages of the control.
This article describes what based on Siemens PLC S7-200 's temperature control system design. The hardware used a CPU model for 226 of S7-200, K-type thermocouple, TD200C HMI and temperature acquisition module EM231. Thermocouple as the temperature acquisition components, acquisition of signal EM231 processing can put data into the PLC for processing, and finally into the man-machine interface displays the current temperature values, so that users real-time understanding of current environmental temperature.