UPS for Arduino IoT

Hi to all,

I am working on RFID Attendance system with Arduino Mega 2560 + EM-18 + RTC - DS3231 + SD card module + ESP8266

I need a UPS(uninterrupted power supply) system for this setup so that it keeps on running in case when there is no power.

I am new to arduino , please guide me how i can build this UPS and power my Arduino, so that it keeps on running.

Any Suggestion & Advice??

Run it from a rechargeable battery.

No need to build a UPS, there are plenty of commercial units out there that plug direct into the mains.

Where is this 'time and attendance system' going to be used ?

thanks for suggestion, can you please share some of the commercial unit Links . I am going to use this for in schools in India. as there is a powercut in remote areas so that why i am looking for some rechargable battery assisted power supply.

In schools, so its a commercial unit ?

Then for anything to do with batteries I would stay well away from DIY, unless of course you are an experienced electronics engineer. And for the rest of it you do need to understand the safety implications of what you are building.

Heard of Google ?

It ought to find plenty of commercial mains UPSs.

... please share some of the commercial unit Links .

Google "low voltage ups". Pick one that matches your budget and availability.