Hi, all.
i want to make a small heater. so i bought 0.1mm x 5mm nichrome strip whos resistance is 2.2ohms per 12 inch.
The length i am using for making the heater is also 12 inch. But when i connect this nichrome wire directly to 12V 5amps SMPS, the SMPS gets shorted.
so i connected 4.6 ohms resistor in series with nichrome strip, but still the nichrome strip does not get hot.
You need just enough NiCr to get near, but not over,
the power supply's current limit. You might reduce the
voltage if it's adjustable, use a series fat rectifier(s) to
drop just a bit of voltage (apiece), etc.
as c_mitra and BradtheRad point out, my comment was wrong
re-reading the thread, trastikata and FvM were likely on the right path
2.2 ohm /m means your 12 inch wire is about 0.8 ohm. the power supply behaved as if it was shorted because it was shorted.
try a car headlight bulb. the H7 is rated at 12V 55W
available at most auto supply store