GSM Based Data Logger is available in a compact design and consumes low amount of power during operation. The Data Logger is a microcontroller based unit with built-in GSM modem which enables continuous centralized monitoring of TR parameters and at the same time notification for any alarm occurrence at central station as well on the configured cell numbers. The Data Logger enables easy and wireless centralized monitoring of all TR parameters like TR Voltage, TR Current, and Reference Potential and optionally AC interference voltage. GSM Based Data Logger ensures optimum functionality for longer period of time.