Timeline for unexpected power supply behavior
Current License: CC BY-SA 3.0
8 events
| when toggle format | what | by | license | comment | |
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| Feb 13, 2015 at 20:06 | comment | added | Some Hardware Guy | If you had a clamp on current meter or probe you could see if any current was flowing from the wall to the power supply after the switch was turned off. Breaking the GND connection, while unsafe might also tell you something. Only do that if you're confident you won't get hurt though. | |
| Feb 13, 2015 at 19:59 | comment | added | bobtato | Yeah, it's the change in behavior when the plug is pulled that seems suspicious-- the power supply shouldn't even be able to tell the difference. I thought about investigating the situation on the AC side, but then I had visions of a tombstone reading "I should have just posted a question on Stack Overflow". It's tricky to jam things into fortress-like UK power sockets because of the safety shutters. | |
| Feb 13, 2015 at 19:19 | review | Low quality posts | |||
| Feb 13, 2015 at 19:44 | |||||
| Feb 13, 2015 at 19:18 | comment | added | Some Hardware Guy | I was thinking it's probably not really drawing 0.5A but he's just guessing that. But yeah it reminded me of getting zapped debugging a circuit where the neutral was broken... There was still a path from live to gnd through me. | |
| Feb 13, 2015 at 19:16 | comment | added | George Herold | An hour seems like a long time for the caps to delivery 0.5A of current... (Though it's not clear, it maybe only the arduino that runs for an hour.) I like your sneak path idea. | |
| Feb 13, 2015 at 19:12 | comment | added | Some Hardware Guy | Or depending how that switch is wired maybe there is a sneak path from line to gnd | |
| Feb 13, 2015 at 19:07 | comment | added | Some Hardware Guy | Although your description of the problem does sound odd. Have you measured (safely) the AC voltage at the input when the switch is turned off. Also I remember there are saftey requirements for large power supplies, maybe there's a circuit in there that's draining the caps when you unplug. Mostly conjecture though. | |
| Feb 13, 2015 at 19:03 | history | answered | Some Hardware Guy | CC BY-SA 3.0 |