IGBT not working?

[dilbert]

Hello, it's nice to be back! I did this board for a wire-fusing purpose: it ignites rocket engine propellant by fusing a 0.5mm^2 NiCr wire attached to "P+ P-" connectors. Fusing the 25mm wire can require as little as 5A*0.05s to 25A*0.5s(ambient temperature, wire is not uniform, contact resistance..)

B+ and B- are the 13,4V LiPo connectors, F is the +5V arduino signal(supposedly continuous, but makes my UT-61E autorange oscillate like crazy),and GCE are the IGBT www.irf.com/product-info/datasheets/data/irg4pc50f.pdf pins.

Trouble 1:when tested with a led+resistor it worked only when swapping C and E(?)
Trouble 2:In the first led test the IGBT stayed on, i figured it was due to the gate insulation coupled with an small capacitance. Adding the 100K bleed resistor to the negative rail seemed to solve it.
Trouble 3:when testing with the NiCr wire it didn't work   

[tom66]

5V is not enough to put a typical IGBT into full conduction. You need about 10 to 18V to saturate it.
Why not use a logic level MOSFET? IGBTs have little use below hundreds of volts. Their main advantage is at high breakdown voltage they offer low on resistance (because their characteristic is diodic, rather than ohmic.)

[rob77]

please post the schematic diagram.... according to the traces on the board it looks like pure