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LED Voltage? Answered

So recently I had an idea to make a steam gun by heating steam with a NiChrome wire driven by a 9v battery, anyway, to keep it safe and so i knew when it was on, i decided to add an LED to the circuit. I went to http://www.hebeiltd.com.cn/?p=zz.led.resistor.calculator to see which resistor i needed. From what i understand, the resistor limits the CURRENT across the circuit. So, what i want to know is whether the Led will work with the first attached circuit and not bun out from the voltage, and whether the nichrome wire and led will work in circuit 2.

EDIITTT: Well, after a few answers, i'm realising i cant run this off of a 9volt, so, what small powersupply could i use?

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jeff-o
jeff-o

Best Answer 10 years ago

A 9V battery isn't enough to power the wire. Either the battery itself will heat up more than the wire, or simply nothing will happen at all.

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rickharris
rickharris

10 years ago

OK Led calculator gives 330 ohms - Personally I would limit the current to 10mA and use a 1/4 watt 680 ohm resistor.


Wire the Nichrome across the battery terminals (via a switch) and it should all work


BUT! 1. The battery isn't going to last long


2. When you put the wire into water it will cool rapidly unless there is sufficient power to boil the water - Power = Watts and a small 9 volt battery isn't going to supply much power. I fear you are doomed to failure.

M


There must be a reason why a typical electric kettle is around 2 KWatts and operates off mains supply.


I DO NOT RECOMMEND YOU TRY THIS WITH MAINS.

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LiquidLightning
LiquidLightning

Answer 10 years ago

Yes but electric kettles have quite large heating coils.

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lemonie
lemonie

10 years ago


Water takes a lot of heating, you'll not get much steam out of that.
And your LED wants to be wired parallel.

L

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steveastrouk
steveastrouk

10 years ago

You will deliver next to no power to the nichrome wire, even shorting the battery, but adding the resistor will make it half of nothing.