I forgot to turn off the power of system before I did some continuity test using a multimeter.

Basically an +-V dual supply was powering a transducer. Transducer was outputting very small offset like 100mV and had almost 8k output impedance so I'm not worried about that much.

But I also did continuity test between V+ and V-; V+ and GND; V- and GND ect.

When I each time heard continuity sound I noticed that I forgot to turn off the power. So I turned off and did the same test.

But many hours later I was afraid if I did damage the power supply.

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What happens if nodes +15V and -15V or + for instance is checked with continuity of a multimeter when the power is on? I know that would be short if it were a wire but is there possibility power supply is not damaged?

  • \$\begingroup\$ I'd expect that the meter, rather than the power supplies, would be damaged, if any damage ocurred. \$\endgroup\$ – Peter Bennett Oct 13 '18 at 1:15
  • \$\begingroup\$ Your power supply is probably fine. Your meter might not be, though; make sure it still works. \$\endgroup\$ – Hearth Oct 13 '18 at 1:39
  • \$\begingroup\$ Can anyone explain how the power supply is protected? I thought continuity test is just a diode:/ \$\endgroup\$ – panic attack Oct 13 '18 at 1:44
  • \$\begingroup\$ Power supplies are often (and lab power supplies almost always) designed to withstand some pretty bad conditions. What a multimeter does to check continuity is the same thing it does to measure resistance, apply a voltage and measure the current, and if the current is sufficiently high it will beep/light up the screen/whatever else it does to signal a positive continuity test. \$\endgroup\$ – Hearth Oct 13 '18 at 2:00

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