Abstract: Remote terminal unit (RTU) valve chambers are mostly located in remote areas, especially China's western region, where relatively large day-night temperature differences often result in an excessively low temperature of RTU valve chambers in winter, mainly because there is not enough heat in the valve chamber and the heat generated by the equipment operation alone is insufficient to maintain the minimum operating temperature of the PLC control cabinet. Therefore, an external heat supply is needed. After two 30 W heating plates are installed on the bottom of the PLC control cabinet, the RTU valve chamber temperature can improve significantly and the PLC control cabinet temperature can increase from 0 ℃ to 6 ℃. If the number of heating plates is increased to 10, the temperature of the control room will be kept at a constant temperature, say 10 ℃, thus completely eliminating common risks of the PLC being at low temperatures such as low working efficiency and even stopping.