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Why is My Nichrome Wire Not Working ? Answered

I'm working on a project I have a 9v battery and breadboard hook up to a Nichrome Wire. But for some reason when I send power straight to the wire the battery overheat. Then when I try to put a resistor between the wire and the battery I have no power reading after the negative power hit go through the resistor.  Please help it will be greatly appreciated!!!   


Good and now what ??

Obviously a 9V internal 70 ohm resistance delivers far less power then 12 Volts of AA cells !

Batteries can't supply all the power you want. They have a property called "internal resistance" which is intrinsic to their chemistry, and limits the power you can pull. The MAXIMUM power you can pull is when the load resistor is equal to the internal resistance of the battery.....which for a 9V rectangular is <<1A.

What diameter nichrome? A 1" length of 0.030 nichrome (having a factional ohm resistance) will heat up to red-hot in about a half-second with just a C-cell battery. Methinks you've repurposed some oversized nichrome that has far too low a characteristic resistance for use with a limited delivery (9V cell) battery,


Here is a chart of what a 565mAh 9V ( internal 6 cells made to deliver under 30ma ) can do .....

While a single C-cell can deliver 7800mAh thats over 13 times more current ! ! ! !


A 9v battery could do the job for the right wire.

* minor correction to my post above: 0.030 ==> 30 ga. Slip of the memory

Anyway, If you do a google search for nichrome wire resistance, you'll find that the resistance drops an order of magnitude from 40ga (~70ohm/ft) to 30ga (6.7ohm/ft)

Wire should be chosen according to your source capabilities and the required heat delivery. As should power sources.

I could easily see using a 9V bat and 40 ga for a model rocket launcher for instance. I could not see it dong much of anything with electric clothes drier nichrome wire... way too low resistance...


2 years ago

The length of the Nichrome Wire makes a big difference in heating the battery or the wire.

Nichrome Wire Is a resistance... Never try a resistor in series.

What is the wire diameter and length ?


2 years ago

Use a car battery, that has enough amps to heat your wire to a nice toasty orange color.


Is it really tat hard to include the details one might need to answer a question?
What resistance is the nichrome wire lenght you use?
90 ohm or higher can work, below that the battery will be unable to supply this.
A good NiMH battery might give more.
But if your battery is overheating I simply say that you forgot to check Ohms law....

But if your battery is overheating I simply say that you forgot to check Ohms law....

....or they think a battery can supply infinite power....

I often think it is much easier than that...
With some questions here I really think the thread starter is a teenager at best and that for some reason Google is not available in their area...