Grounding Issue in DIY Circuit Answered
Hello everyone, I'm having a bit of a problem getting my LM317 soft-start circuit to function properly.
If you'll take a look at my schematic, I've built everything on the schematic up until the relays and diodes get involved (specifically where the output forks into two). In order to check that I soldered the board correctly, I hooked an LED up to where the fork would be to make sure the soft-start worked.
Here's where things get funny: If the LED is connected to the rectifier's negative, the LED behaves as I expect it to, with a slow turn-on. However, if I keep the LED connected to the same positive point, but hook the led directly to ground, nothing happens. In fact, using a multimeter showed that no voltage would flow to ground from the positive, but that 14 volts were flowing between the same positive point and negative.
I need voltage to flow to ground, this is a ground safety interlock for a welder I'm working on... does anyone have any suggestions?
Thanks for reading :)