A sensor equipped portable alarm device that also has an input port for connecting to an external sensor so that either the internal sensor or the external sensor can be selected using a sensor select switch. Furthermore, the alarm device has a timer for setting a delay time so that errors arising from immediate action on start-up can be avoided. In addition, the device has a magnetic base for mounting on a magnetic surface and dismounting when the device is no longer needed. Moreover, a rechargeable internal battery is used as an internal power source for the whole device, but power drawn from an external power source can also be used as well. Therefore, the device is portable and can be used anywhere.