LED Voltage?

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?

Picture of LED Voltage?
sort by: active | newest | oldest
jeff-o6 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.
rickharris6 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.


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


LiquidLightning (author)  rickharris6 years ago
Yes but electric kettles have quite large heating coils.
lemonie6 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.

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.