One more question about CAPS, hopefully. I see a couple on Mouser, both 22000uF 35V, same physical size but slightly different price and a couple specs, ESR and ripple current. The values are very close, but I'm not educated enough to know if they will make a noticeable difference.
SLP223M035H9P3
381LX223M035A052
SLP223M035H9P3
381LX223M035A052
LEDs are very bright these days so a 10K resistor in a 24V power supply will give a very bright light but still acceptable current draw.
But with a 10K resistor, I would not expect the multimeter to light up the LED.
I suggest checking the resistors to make sure that they are not shorted in some way.
Please post pictures of the top and bottom of the power supply board.
But with a 10K resistor, I would not expect the multimeter to light up the LED.
I suggest checking the resistors to make sure that they are not shorted in some way.
Please post pictures of the top and bottom of the power supply board.
Measure them with one probe on each leg of the resistor on the same side of the board (the top). They should be ~10k => ~10,000 ohms
Make sure you are reading your DMM properly and/or take a picture of the way you're measuring the resistors and the meter during measurement. For many DMMs it will show a small designation for kilo or mega on the display.
With these boards it would be odd to short the resistors (but it could happen), but a 10 ohm instead of 10k ohm could be part of what you're seeing. Still odd that your DMM would put out enough voltage to light them even w/o a dropping resistor. If you have a spare LED, just set your meter to continuity and touch the probes to the legs (flip it just to be sure you cover both orientations if you're not sure). Then you'll at least know if your DMM puts out enough voltage to light the LED by itself. Then you can verify that you've got an appropriate resistor in place and move on from there.
Perhaps you had the caps populated and they charged?. Don't forget to post the other pics Ben had suggested.
Edited to add - I have one type of DMM where the actual switch position can be for resistance, continuity, or diode check based on a push button selector. Make sure you don't have your DMM set to diode check, or it will likely light up the LED and not give you what you want. That's my final guess.
Pic added to show one of mine in the wrong setting.
Make sure you are reading your DMM properly and/or take a picture of the way you're measuring the resistors and the meter during measurement. For many DMMs it will show a small designation for kilo or mega on the display.
With these boards it would be odd to short the resistors (but it could happen), but a 10 ohm instead of 10k ohm could be part of what you're seeing. Still odd that your DMM would put out enough voltage to light them even w/o a dropping resistor. If you have a spare LED, just set your meter to continuity and touch the probes to the legs (flip it just to be sure you cover both orientations if you're not sure). Then you'll at least know if your DMM puts out enough voltage to light the LED by itself. Then you can verify that you've got an appropriate resistor in place and move on from there.
Perhaps you had the caps populated and they charged?. Don't forget to post the other pics Ben had suggested.
Edited to add - I have one type of DMM where the actual switch position can be for resistance, continuity, or diode check based on a push button selector. Make sure you don't have your DMM set to diode check, or it will likely light up the LED and not give you what you want. That's my final guess.
Pic added to show one of mine in the wrong setting.Attachments
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