Jump to content

My Standby Power System


Recommended Posts

Quit often I have been teasing people about their expensive batteries and standby system and referred to the way I have done my house.  Been a little occupied as my wife wanted a library. So I converted our atrium into a library and my other projects rested a bit.

As I am doing the wiring and power installation I thought it would be nice to show others what I am doing as it is very cost effective.  At the end I will supply all wiring diagrams a full list of components and costs.  So to start she wanted specific LED lights and they work on 11V.  Trust me 12V and you blow them. Thus I did a little variation on the same product.

This is the LED and 5 of them. I will put a photo in without the light on.




Edited by Erastus
Link to comment
Share on other sites

The photo below have all the components except for the relay and light switch that I will add later.

I am using a small 24V power supply set to 27.2V  This is a "trickle" charge voltage/current for these specific batteries
The wiring is very simple as can be seen.

The little regulator is 6V - 36V input and the output set to 10.5V and can supply 5 amps to ensure I do not blow the led's.

The total current drawn by the regulator and 5 led's is .6A.  The batteries are 7amp hr therefore I should get a backup light time of at least 10 hours.
The batteries are permanently wired currently and when Eskom goes off the LED's simply stays on. Therefore these led's are permanently on in the current way of wiring.  The power consumption is 16W or 390W per day or 12Kw per month or R24 per month.

When fully wired it will only be on when the lights are switched on or automatically when Eskom is off.  The wiring will be that when ever Eskom is off these 5 lights will be on.


Power supply  R220
Regulator         R 38
Batteries         R  210  each

The life expectancy of the batteries are 5 years.

I put all together as a test and will show how I do the rest of the wiring and installation when I mount the units in their permanent place.

If it is boring please let me know and I will stop.

I am simply doing to show the cost effective way of not sitting in the dark at an affordable cost.







Edited by Erastus
Link to comment
Share on other sites

The things we do for our wives.  :)

When you are finished and have an enclosure for everything, don't forget switches and fuses.

Besides my lovely new Sunsynk 8K inverter, years ago I have also wired my house up for 12V DC LED lights to beat load-shedding.

I used a 16 button RF remote to switch on the different lights. The units feed was fused, and each LED light was fused.

The MOST important thing to remember about DC is don't mess with it, or your house will burn down.

Have decent wiring, and FUSES.

Enjoy your project and light up your house while your neighbors are in the dark during load-shedding. 😆





Link to comment
Share on other sites

8 hours ago, TimCam said:

The MOST important thing to remember about DC is don't mess with it, or your house will burn down.

Have decent wiring, and FUSES.



When done it will have a sensor you move into the room it switches on you move out it switches off.
This was simply done to check regulator and current..

There is still coming a switch over relay to switch to batt when Eskom is off and the sensor for movement and a small DB.


Link to comment
Share on other sites

Now that the lights all wired etc I am installing my system:

Radio transceiver:

Microwave Human detection. This device detects human activity and will send the detection to the cpumdet.jpeg.d0d921a007b4a20f7b60f03722ecdac2.jpeg

The CPU board:





The cpu is synced to a master that is a very basic controller and web interface.

All my backup units has this device and monitors the Batt Voltage.  When it get to low the CPU switched the lights off or over to normal power.

The CPU's are synchronized and will only start charging during the day  or any time it is programmable.

Thus during the day the batteries get charged  and at night when there is movement the lights go on. 

At night the CPU will switch the back up lights on when there is no mains.  It will also detect the signal from the microwave unit and then switch the lights on and off depending on the on time which is programmable the light will stay x minutes on after the person left the room.

It will use VBatt until the V is low and then switches back to Eskom.  The batt are selected to last +/- 10 hours.

All Batt voltages are send the the master unit and from there all Bat units are monitored.

I use a bigger 24V power supply and batteries for the TV. it also has a 24V - 220V for the LED tv ...

The comms device cost is  R90  the Micro wave detection is R45

Thus a smart systems cost is +/- R 1200

When built I will add more photo's with the relays and wiring diagram. 





Edited by Erastus
Link to comment
Share on other sites

  • 3 weeks later...

The most basic version can even be without the control relays.

This version charges the batteries give me +/- 6 hours standby for 5 Lewd down lighters.

The 220V switch over switches over as soon as there is no 220V.

Nothing fancy but works like a dream.

The control relays has 2 purposes.

  1. The on/off switches is made to look like a book in a bookshelf so I do not want any thick cables.
  2. The control cct with central control and wireless communications will follow soon.

This version is an illustration of a Eskom light back up system for less than R900.



Link to comment
Share on other sites

  • 5 weeks later...
On 2021/09/21 at 8:02 PM, TimCam said:

Once you're complete with your install, Eskom won't load-shed for months to come. 😆😂 

And how right you are.  But its there for emergency lights as well.  I have a few of them that at night via CPU I can switch to off grid and chrage during the day via solar.

A cheap version to replace expensive batteries and inverters.  That's more my aim. 8 of these batteries runs my whole house lights when thare are any power issues and during the night I can run of batteries and charge it during the day via solar.

All CPU controlled.

Link to comment
Share on other sites

  • 1 month later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Create New...