Yes, and the fact than you can ground either output terminal is a sure sign that they both are floating with respect to earth ground and the power supply case. The earth ground terminal is the yellow one in the middle. Green is a more common color for it.Here it is ... so its normal when I ground Negative terminal to get +12V reading
And obviously normal when I ground Red terminal positive I get +12V as well ...
by Duane Benson
by Jake Hertz
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