Currently I have this UPS power setup for my Router with the help of a DPDT relay so that the router works when mains power supply fails. The working principle of my project is real simple. Two separate power supplies are connected to a DPDT relay where one the power supply powers the relay coil and a battery. When the mains power fails the relay coil is no longer powered and switches to the battery supply. I used a relay mainly because it provides full isolation between the 2 power supplies.
My concern is that in my current setup the relay coils are always powered on when the mains in available which according to Omron, might lead to a contact failure or coil burnout in the long run.
So is there any a way to replace my relay setup with a more reliable component? maybe a Mosfet or SCR? Will the coil really get damaged?
So I went through the below suggestions and decided to change my setup into this new one which might be better than my first one. These are the changes that I've made.
- I got rid of the 9V wall wart and now it's just a single 12V 2A wall wart that powers everything.
- Now uses a CC CV Buck converter with Li-ion charging feature to charge batteries instead.
- Added a 2 Series Battery Management Module with Cell balancer feature so that I could now use 2x18650 cells for longer runtime and better voltage to boost
- Replaced the Boost converter with a Buck Boost converter.
- Scrapped the Relay.
So, will my new setup work as intended? or is there any problem? or maybe place to improve?