Powering Konnected from existing alarm panel/battery

I've got an existing alarm panel with a 12V SLA battery. The panel has a 17V AC input and connects a charging circuit to the battery, and also has 12V aux power output.

I've connected the Konnected board and the existing powered sensors up to the 12V aux power from the alarm panel, and this seems to work fine when the panel is running on mains or battery - giving me a battery back up.

However the battery and alarm panel take up all the room inside the cabinet. I'd really like to rip out the alarm panel board and replace it with a smaller board that can charge the 12V SLA battery and supply the 12V to the Konnected board and the powered sensors. Ideally it would also have outputs to indicate if it is running on mains or battery, and if the battery is low - something the alarm panel does natively but doesn't expose as outputs.

Has anyone come across or know of a board like this?

Here is one option:

AC/DC Open Frame Power Supply (PSU), Charger, 1 Output, 40 VA, 24 V, 800 mA

Input Voltage VAC:: 12V / 16.5V / 24V

I use this with my set up. It provides 12VDC to 3 Konnected boards and powers 1 tablet via a 12V to 5Vdc converter. It also charges a 12V backup battery and will power the system if AC power is lost. No indication for batter life or condition though.

Awesome, thanks for sharing that.


Would you be able to share how this is exactly setup? Looking to use existing PSU that routed to my alarm panel but a bit confused on how you are powering 3 boards a tablet and a battery backup. Thx in advanced!

 Please see datasheet for the Elk P624 power supply:

ELK P624 datasheet

My setup is shown in the attached image.


The connection from the ELK power supply to the 12V to USB converter is via the 4 wires in the wall used for the old alarm system keypad. The 12V to USB converter is in the wall behind the tablet about 30 feet away from the alarm panel.

The 4 way splitter is used to connect 3 Konnected panels to the ELK power supply. The 12V-5V USB converter is connected directly to the ELK 12V output.

I attached a picture of my set up before  I received my production boards. I have since cleaned up the wiring and replaced the DIY boards with production boards. Really need to get an updated picture.


The relay in the picture is used to open/close the garage door. Since there is a 4-conductor cable run from my panel to where my garage door controls are I put on pair to use for that function. I have a wireless sensor on the door for open/close status.

I am currently researching a replacement for the ELK power supply with a higher current output. I am powering three Konnected boards, the 12V-5V USB converter,  and a 700MA siren from the ELK. So far no issues but I would like to have a beefier supply. Have not pound one yet with the battery backup feature that the ELK has.

Thanks Ed, that's really useful. Please let us know if you find something better.

I'm wondering if it would be possible to use the power across those two indicator LEDs as inputs to get Home Assistant or SmartThings indication whether the AC or DC is out? Or whether it is better to try and sense that separately?

What about http://www.mini-box.com/picoUPS-100-12V-DC-micro-UPS-system-battery-backup-system?sc=8&category=1264