DSN-DM indoor electromagnetic lock is used in indoor high-voltage electrical equipment with rated voltage of 3.6, 7.2, 12, 40.5KV and frequency of 50Hz. Matching with the sensor, it has the function of reflecting the live condition of the high-voltage circuit and implementing forced locking. Assembled in the front and rear doors of various switch cabinets and other parts that need to be locked, it can reliably prevent electrical misoperations, prevent mis-entry into the live interval, and improve the anti-misoperation performance of supporting products.