I am working on a project that will ignite a match on command using Arduino. My external power supply, when connected to a thin strand of wire, heats up a wire causing ignition. To control this I want to use an NPN transistor, with my external power supply connected to the emitter and collector, and when I want to heat the wire I will supply power to the base of the transistor, allowing the circuit to close and the wire should heat up.
My problem is that there doesn't seem to be the same current flow through the wire when the transistor is in place and power is supplied to the base, compared to when I remove the transistor from the circuit. In this closed circuit (with the transistor in place), the wire doesn't heat up, which confuses me because I thought that when power is supplied to the base, it is as if there is a free flow between the emitter and collector. I measured the voltage when power is applied to the base of the transistor, and this voltage is identical to the normal voltage of the power supply (without the transistor), which makes me think somehow the current flow is being reduced.
Is it possible that the transistor is reducing the current flow when power is applied to the base? Why is this? Any suggestions to fix this?
My external power supply is a 3.7v 500mAh battery, and the power to the base of the transistor is about 40mA. The transistor I am using is NPN transisto
Thanks in advance.