I recently bought a basic Digital oscilloscope and wanted to power my oscilloscope from computer UPS 600va. I have two questions:

1- Can the UPS give isolation from main supply? ( like alternative to isolation transformer)

2- The output of the computer UPS waveform is "simulated sine wave", will it affect performance of oscilloscope?

UPS datasheet: https://www.luminousindia.com/media/catalog_pdf/LI%20UPS.pdf

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    \$\begingroup\$ You should not be floating your scope. Float your device under test, not your scope. Floating your scope makes things like all the BNC exposed connectors, probe ground clips, and the voltages right behind the knobs and buttons on your scope float all the way up to whatever you are testing which is dangerous. \$\endgroup\$ – DKNguyen Jul 2 '19 at 4:58
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    \$\begingroup\$ First, although most power supplies are not officially certified to use with modified sine wave as power source, but often the majority of switched-mode PSU should work without problems, including oscilloscopes, so yes, you can use a UPS to provide backup power to your scope. Next, if you UNPLUG your UPS and run it on batteries, the inverter is no longer ground-referenced, and it does provide isolation in a sense, but it's dangerous and YOU SHOULDN'T DO IT, see electronics.stackexchange.com/questions/73991/… \$\endgroup\$ – 比尔盖子 Jul 2 '19 at 5:30
  • \$\begingroup\$ after long surfing about powering oscilloscope, i wrongly understand to isolate oscilloscope instead of testing unit, thank you all \$\endgroup\$ – noob_no1 Jul 2 '19 at 6:35

1- does computer UPS give isolation from main supply? ( like alternative to isolation transformer)

No, "UPS 600VA" it is not isolating from main supply

2- output of the computer UPS waveform is "simulated sine wave", does if affect performance of oscilloscope

No it doesn't affect the performance because it converts to DC inside the oscilloscope.

A simulated sinewave is basically a pulse width modulated squarewave, with a proper output and/or input filter i would not expect any issues.

shall i use computer UPS for oscilloscope

No, I don't see any reason for this unless you live in a place with a lot of short-term power outages.

  • \$\begingroup\$ A UPS could be used to provide isolation from the supply. Plug in the UPS for a few hours to charge the battery inside. Then unplug it from the supply, and plug the oscilloscope in to the UPS. \$\endgroup\$ – Simon B Jul 2 '19 at 9:45
  • \$\begingroup\$ I think you are wrong. When you unplug UPS from the mains it is pretty much isolated from the mains. \$\endgroup\$ – Chupacabras Jul 2 '19 at 11:47
  • \$\begingroup\$ This is not the purpose of a UPS @Chupacabras Never float a oscilloscope: electronics.stackexchange.com/questions/73991/… \$\endgroup\$ – Daniel K Jul 2 '19 at 13:22
  • \$\begingroup\$ I didn't say it is a purpose of any UPS. I just commented on your statement which is false. Oscilloscope connected to UPS (which is disconnected from the mains) is isolated from mains. No matter whether it is recommended or not. \$\endgroup\$ – Chupacabras Jul 2 '19 at 14:42
  • \$\begingroup\$ For sure it is isolated but nobody will operate an oscilloscope like that. Therefore I did not consider this case. \$\endgroup\$ – Daniel K Jul 2 '19 at 15:53

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