1. Dynam0

    Making a portable battery powered mini pc

    As the title says, i want to build a custom mini pc. The reason i'm not buying just a laptop or a mini pc are many...First of all i want something that will be able to be upgraded in the future without problems, that's why i'm putting a Micro-Atx inside instead of a laptop mobo. 2nd i want...
  2. guy_c

    Continues sla battery charger

    Hello, We have often mains shortage in my village and i want to use (create? preferably buy?) 12V ups i.e. continues 12V supply, mainly for an arduino+enet shield, a router modem and in rare occasion a ~1A siren. I bought a 9AH sla battery snd a 'smart' charger but am disappointed that the...
  3. J

    Can I mix Amp Hours (Ah) batteries in a UPS?

    I have a Trip Lite UPS that has two 12-volt 9 Ah batteries in series that I need to replace. I have an 8Ah and a 9Ah batteries on the shelf. What would happen if I were to connect these in series?
  4. G

    12v DC 7A UPS from Li-ion Batteries

    Hi All, Complete beginner here so please bear with me! Trying to work out a solution for changing the main battery on my portable video switching system. The project is powered off a single 12V DC 8A V-Mount battery which powers the system perfectly. That said, I can't find a UPS with the...
  5. E

    Feeding load with two 220V AC power supplies to reach uninterrupted power supply.

    As shown in the diagram, I am trying to connect two power sources to load. The battery source is for emergency in the case of power outage of the wall source. I want the switching to be instantaneous with no interruption of power. What is the best solution to this problem? Is there a board...
  6. lefterisgar

    DIY Arduino-powered 12V UPS suggestions | HELP NEEDED!

    Firstly my wishes to whoever reading this piece of text, have a nice year and I hope that everyone is doing fine in this current pandemic and I think this is going to be a piece of the past very soon... I'm also sorry for two things regarding this thread: I'm not a fluent English speaker. I...
  7. K

    Can a car battery possibly kill an otherwise OK UPS?

    In the hope that there are some experienced people here, I am trying to find the reason why and how I killed a UPS. To make a long story short I attached a car battery to an old MGE Nova AVR 600 (360W/600VA) for testing to see if it can handle a single computer. When I disconnected the line...
  8. L

    Passthrough charging question

    I'm trying to design a passthrough charging system for my rpi4b which requires 5v 3a max. I assume it means the regulator needs to handle 6a output if it handles the lipo charger too. I drew out a schematic with power transistors for control, but I'm not sure I set it up correctly. Will this...
  9. S

    Need help with DC-UPS

    I need an DC-UPS that can handle at least 300W, but I couldn`t find anything. So I come up with this: Battery: 4s2p Li-ion (3.7V) PSU: 14.8V P-Channel MosFET: IRF4905 (maybe? idk) N-Channel MosFET: idk Will it work? What should I change? Do you have any UPS suggestion? Thanks!
  10. Rahulk70

    Identifying the input power leads of a salvaged UPS transformer for projects

    Hello everyone, I'm writing this post mainly to help others who have had asked many questions in the past how to figure out the input supply leads (115V or 220V AC wires) on a salvaged UPS transformer. These transformers from a UPS are quite bulky and quite powerful and can be very useful in...
  11. B

    SLA Battery Charging/Maintenance

    Is using a UPS i.e. APC Smart-UPS (4 battery) a recognized way to charge and maintain SLA batteries (AGM) throughout the year? Given that the batteries should be discharged about every 3 months?