... 12. Wellheads, boat, vehicle;13. Energy saving, street lights control system;14. Valve controls;15. Transformer stations; 16. Unmanned machine ... stamped alarm messages; Backup rechargeable battery inside, can work for 24hours when power off; Can be operated from anywhere, ... Level Sensor, Oil Overflow Level Sensor, Water Leak Sensor, Temperature Sensor, Door Sensor, PIR Motion Sensor, Smoke Sensor, Gas ...