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How to heat up nichrome wire? Answered


Think a bit more about this: A typical room heater needs about 500W. On 12V, assuming as many have poined out, that your source voltage doesn't droop under load you would need 500/12 A, or 41A from your supply.


8 months ago

but does a thicker wire heat up more easily? And why isnt my drill battery heating up the wire that much?

No, thicker wire is more difficult.

The thicker the hotwire, the more current that's required.

For instance, a couple inches of 40 gauge wire takes a couple amps at a couple of volts. Use a DC power source please. You can look up the resistance per foot of resistance wire via google/bing/etc. There are often tables presented at such sites that spell out the operating requirements.

An electric dryer's hot wire, on the other hand, is so thick it takes considerable voltage and amps to get it glowing.

Use a DC power supply or battery. No one wants you injured or killed from fussing with line current.

(The higher the gauge, the thinner the wire)


That is what may have tripped up the OP


8 months ago

According to my multimeter, longer wire = less amps drawn which makes no sense to me. And im trying to make a 12 volt heating system with a fan and nichrome wire as a coil to heat up the room. I know that 36 gauge wire is too thin for that but if the battery cant even heat up a 36 gauge wire how can it heat up a 22 gauge wire? (Thanks to everyone helping)

Resistance according to Ohms law = Volts / Current so reducing the resistance will cause a bigger current to flow IF the voltage is fixed.

For example I made a hot wire cutter using a 12 volt car battery as source, My wire was a guitar top E string. Worked fine, with the addition of a 5 ohm resistor (established by experimentation) I was able to cut the foam without making the wire red hot..

Electricity is made up of 2 components - Voltage and Current,

Voltage is equivalent to the pressure and current to the flow rate.

As you "push" electrons through a resistance (your nichrome wire) you make them do work which heats up the wire.

If the resistance is low much more current or voltage is required to provide the necessary "friction" a thicker wire has lower resistance.

Voltage is measured in Volts and Current is measured in Amps.

Voltage x Current = Watts which is a measure of power.

Relatively low currents (THOUSANDTHS OF AN AMP) can kill you.

In the UK voltages over 50 volts are considered dangerous.

If you tell us what your trying to do you may get more specific advice.


8 months ago


You must provide the correct voltage for the specific length of wire and current required to heat the wire of a given gauge hotwire. Thicker wire requires more "push" than thin wire.

Pass electricity through it

NOT mains electricity - unless you know what your doing.