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Class 2 SMPS - Removing the Y capacitor - Good design solution wanted !
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Ian.M:
I see a 'Y' capacitor! C006 (top left) links FG (which we can assume is incoming PE Ground) to the negative side of the primary DC bus, and the chassis ground symbol links FG to the output ground.
Kleinstein:

--- Quote from: Ian.M on September 16, 2023, 07:31:50 am ---I see a 'Y' capacitor! C006 (top left) links FG (which we can assume is incoming PE Ground) to the negative side of the primary DC bus, and the chassis ground symbol links FG to the output ground.

--- End quote ---
It is supposed to be Y class capacitor - but in the BOM it is only listed as 400 V type, though the specific type may be OK
BrianHG:
High quality USB-PD wall warts without Y caps, double shielded transformer core and extra wide gap isolated transformer secondary windings exist, even without even a GND pin and they have full approvals.  But if you want the full 60 watts, you need an PD negotiating IC to receive the 20v, otherwise you are stuck with 5v, 2amp.  On the up side, if you gone through the trouble, now your device is also compatible with USBPD power packs.
Nominal Animal:

--- Quote from: smile on September 16, 2023, 07:21:32 am ---Can this be used as reference to modify Meanwell PSU? Like the RPS-300 27v or LRS-350 48V?
--- End quote ---
Mean Well already manufacturers many class II isolated power supplies, for example the HDR series DIN rail ones (HDR-15 to HDR-150), IRM encapsulated board ones IRM-01 to IRM-90), and others.

(RPS-300 is class I isolated, but medical safety approved, i.e. with less than 150µA leakage current.  Open the Mean Well AC/DC Product List, and examine the model-specific PDF files on the right-hand side, to check for isolation class, EMI, and safety specs.)

For high power class II isolated medical safety approved supplies, I'd look at RPS-400 and RPS-500 series.
coppercone2:
if the earth is  ground reference, its surprising you can pick up a shock, unless the impedance of the earth wire is too high.

in a sense you are dealing with crappy infrastructure in your home/buisness no?

I wonder what happens to these devices if you get closer to the g rounding rod/panel and also start lowering impedance with straps to make a RF ground
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