Circuit Draining Batteries

Thread Starter

truwebs

Joined Apr 2, 2016
78
Hello All,

Been a while since I have been here. Have received some wonderful help here before, hoping I can get a little more help.

I have created what I thought would be a very simple circuit using a string of battery powered micro led lights and a magnet switch.

I placed a magnet switch inline to the circuit in hopes that the lights would turn on when a door is opened and then turn off when a door is closed. The circuit does appear to work as I had hoped. Lights do turn on and off as desired by opening and closing the door, but....

After 12-24 hours I will open the door and the lights will not turn on. It appears the batteries have been drained. I have gone through 3 sets of batteries in about three days. What is happening? Hope you can give some insight.

See images of items used and connection. This was supposed to be a cool feature of a restoration project I did. You can see the full project here.
lights.jpg
switch.jpg
Connections.jpg Setup.jpg

Thanks for your help,
TRU
 

Ylli

Joined Nov 13, 2015
1,086
I'm a little confused by the way you have the switch wired. Do you by chance have the battery tied to the common and the NO, and then the LEDs tied to the same points? The LEDs would go on and off that way, but the battery would be shorted when the LEDs are off.

You need to have the switch in series with the LEDs. Battery + to the switch common, switch NO to the LED string anode (positive lead), LED cathode (negative lead) back to the battery negative.
 

BR-549

Joined Sep 22, 2013
4,928
It appears to me that you have your batteries wired in parallel. Measure the current and install appropriate diode in each lead to the NO contact.

Double check and make sure lights are really going off.
 

Thread Starter

truwebs

Joined Apr 2, 2016
78
I'm a little confused by the way you have the switch wired. Do you by chance have the battery tied to the common and the NO, and then the LEDs tied to the same points? The LEDs would go on and off that way, but the battery would be shorted when the LEDs are off.

You need to have the switch in series with the LEDs. Battery + to the switch common, switch NO to the LED string anode (positive lead), LED cathode (negative lead) back to the battery negative.
See my drawing below. I believe there may be a resistor integrated into the battery pack after the battery pack switch.
drawing.jpg
 

Thread Starter

truwebs

Joined Apr 2, 2016
78
Thanks! Correction has been made. Light appears to be working as is should. If the batteries are dead 24 hours from now you'll be hearing back from me. ;-)
 

Thread Starter

truwebs

Joined Apr 2, 2016
78
Since I was logged into the site just thought I would give an update. Circuit is working great! Batteries still have life!
 
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