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9v Batteries Powering Multiple Items

  1. Jan 26, 2008 #1
    I'll start with the typical "I'm new to this and don't know much about DC wiring and power." I'm trying to wire 10 flickering candles that each run on a single 9v battery into a fake cake and do so in a manner that will make pulling the batteries out quick and easy without having to remove each individually, and have it all part of a system that can be turned on and off via a switch. From what I was reading I figured I'd be able to create a container that I could insert 10 9v batteries into and have that wire into each candle through a parallel wiring scheme to increase the power output while keeping the voltage the same. This unit only needs to power the candles for about 15 minutes at a time, and a new 9v will power a single candle for about 80-90 minutes from our tests. Once I had completed this project everything seemed to work fine for the 3-4 we ran it using the same set of batteries but then I started running into problems after the initial set was replaced. The candles arent staying lit very long and seem to be draining power very quickly causing the candles to fade rapidly and be out completely out in a matter of minutes. The voltage seems to be dropping rapidly when I meter run a meter through it, and this is happening with entirely new sets of batteries. Anybody have any explanations or suggestions as to what may be happening here and how to fix it? I wouldn't be that surprised if this just didnt work from the start, but Im baffled by how it worked fine until we started changing the batteries.
  2. jcsd
  3. Jan 27, 2008 #2


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    So a single battery will power a single candle for 90 minutes, but ten batteries only power ten candles for 3-4?

    Perhaps you could draw out how you've wired the system up?
  4. Jan 27, 2008 #3


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    If you are wiring batteries in parallel, internal resistance of one (bad/used) will sink power from the others.
  5. Jan 28, 2008 #4


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    Other than the 'single switch' aspect, I suspect that you might be farther ahead to just buy the 'button battery' artificial candles. My wife sells them for a couple of dollars each at her 'cheap' store, and they're good for more than 12 hours. There's just a simple twist cap on the bottom to turn them on and off.
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