For someone with no knowledge in electrical engineering, is there a way to check if a device is "grounded" (?) and safe to use?

It is not uncommon when shopping for appliances online (eg. lamps), mainly with those imported from China, to find reviews warning about a missing "grounding" and the associated dangers. The danger behind it seems to be that in the case of an internal failure, a live wire could come in contact with the metal chassis and electrocute the next person to touch the device. This also means that in a device built to safety specifications, there is some sort of failsafe guarding against this danger.

If one were to receive an electrical appliance with unknown safety mechanics and potentially missing/forged certifications, how could one reasonably check the product regarding safety?
Does this process differ depending on the outlet it's built for (US vs EU etc)?
Can this check be done without disassembling the device, wherein a layman could inadvertently destroy the safety features?

  • 1
    \$\begingroup\$ Choose where you buy from either cheap OR safe... Reminds one of the old adage "there are old pilots and bold pilots but few old bold pilots"... \$\endgroup\$
    – Solar Mike
    May 30, 2020 at 22:02
  • \$\begingroup\$ As a rule of thumb, I never knowingly jeopardize personal safety for some savings. But this does not protect me from an expensive package containing a rebranded cheap product. There might also be cases where an appliance of unknown quality is already available, and buying new would create unnecessary waste. Whatever the reason, it would give peace of mind to not be forced into blind trust regarding personal safety. \$\endgroup\$
    – René Roth
    May 31, 2020 at 7:48

1 Answer 1


With respect to grounding, the key property is, that all metal parts that are exposed and can possibly be touched by a person, have to be connected to protective earth. With a multimeter in beeper mode, you can check if all of those parts are connected with the main plug's protective earth contact.

But depending on the kind of device, there are other things that can potentially go wrong and be a risk. For example, I once had to do with cheap chinese usb wall chargers which used really low quality transformers with questionable galvanic isolation. If something goes wrong in this case, your life depends on the rccb working properly.

In my opinion you need some experience to really qualify whether a device is safe to use or not and you may have to look at the electronics inside.


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