JDA-2240 comprehensive emergency protection system fully meets the requirements of the document No.  240 of the Transportation and Supply Equipment Letter of the State Railway Group Co. It is an emergency protection system developed mainly for traction substation encountering lightning strike, high-voltage switch insulation breakdown, earthquake, fire, DC power supply failure and other kinds of fault conditions that may affect the normal operation of the substation automation system and make the primary equipment lose protection and affect the safe operation of the traction power supply system. The system alarm and trip functions are grouped together, and each group is independently logically programmed and independently thrown back according to the collected signals. The system mainly consists of JDA-305B comprehensive emergency protection device, independent emergency power supply, external trigger signal, protection control isolation circuit, etc. It can meet various power supply modes such as AT, BT, direct supply, etc. It can be decentralized installation or centralized group screen, and can adapt to the requirements of new high-speed 27.5kV or meet the transformation of existing old lines; the insulation index of the device can meet the application conditions of high-altitude areas, and the fully sealed, anti-vibration structure and wide temperature working range of the device make it possible to operate reliably on the switchgear.
The system has been popularized and applied in many railway lines such as Yongguang, Dazhang and Beijing Shenyang.