Can anyone explain these symbols to me?
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there's the earth/ground symbol in three variations (that I know) "white on green", "black on yellow", and "white on blue"
I know that white on blue labels usually indicate mandatory, but what I couldn't figure out if that meant it was already bonded to earth, or I needed to provide an external earth connection to it.
It's a label I have on a rackmount PDU.
Ideally I'd use that point as my earth point, and the rest of my earth would be tied to that, but if that is not the case then I would need to get access to the earth from the main cable plugge din