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Why are my batteries getting hot with the switch turned off? Answered

I built a simple circuit with 2 AAs, a SPST slide switch, 1 red LED and a 47 ohm resistor. With the switch in the off position the batteries get hot to the touch. All the connections and solder points were wrapped with heat shrink tubing so nothing is touching that shouldn't be.  When the switch it turned on, the LED lights the way it's supposed to.  I assume it's a bad switch but wanted to get some other opinions.

Tags:LEDs

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user
orksecurity (author)2011-07-24

Examine your circuit. It sounds like you're turning off the light by shorting the batteries, which is definitely not what you intended.

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user
sycor (author)orksecurity2011-07-24

I think is exactly what's happening. After looking into it, I think I wired the switch wrong. Thanks for the replies guys!

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user
rickharris (author)2011-07-24

I would have thought 47 ohms to be a bit low for a standard LED.

BUT, I am guessing here, the switch has 3 connections on it have you connected the middle connection to one end and made sure there is NO bridging to the 3rd connection?

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