I'm working with 12 - 24v DC supply delivering 2 - 4 A through a small heating element. I want to be able to detect if the element goes open circuit. A parallel LED + resistor of course shows voltage is applied but not whether current is flowing in the other branch. I understand the voltage is too low to use a neon bulb that would light on open circuit. I'm thinking a parallel capacitor + resistor could be the starting point as the cap would not charge to supply voltage while parallel current was flowing. I need a very simple set up as I will be constructing over 70 such heating units.
Nelson
Nelson