The electrical earth connection on the terminal block is not connected to the case, that must be connected externally by the user. As long as you have both points earthed it is safe.
Thank you very much. I was really confused. 😱
However i find a little weird that a smps does not come with its metallic enclosure already earthed to the mains ground terminal 🙄
Anyway .... very very good to know. Thank you so much again 🙂
As far as I'm aware, most encased switched supplies do not, in fact, connect the enclosure and any part of the terminal block. Doing so would mean a stray wire could cause havoc and be a fire risk.
On an ordinary PC power supply, the earth ground is definitely connected to the chassis. The ground / returns on the ATX power connector is also definitely connected to the chassis.
On the Meanwell I have, the earth ground is definitely connected to the chassis. However nether the (+) nor (-) output terminals are. Why? So the user can connect the one of their choice to earth / chassis ground. Maybe an application needs a negative supply voltage, in which case the user would connect the (+) output to earth / chassis ground.
Try connecting the (-) output to the Gnd terminal on the Meanwell with a short wire. Not "L" or "N" - Gnd; the one with the green wire.
On the Meanwell I have, the earth ground is definitely connected to the chassis. However nether the (+) nor (-) output terminals are. Why? So the user can connect the one of their choice to earth / chassis ground. Maybe an application needs a negative supply voltage, in which case the user would connect the (+) output to earth / chassis ground.
Try connecting the (-) output to the Gnd terminal on the Meanwell with a short wire. Not "L" or "N" - Gnd; the one with the green wire.
The problem is, once you go IEC Class I you'll probably run into trouble with unbalanced connections. Some car audio components are using pseudo-balanced hookup for their RCAs for this reason.
Meanwell's installation manual is not specific on the matter. Instead of a hard connection, something like (2x 470 ohm 1/4W in series) in parallel to a ~10 nF Y class safety capacitor may be a better idea... leave out the R if there is a possibility of bad mains miswiring.
Any luck with the noise issue? If you google SMPS burst- and skip-mode you will see what I meant in post 13. It may or may not be your problem. My suggestion of loading the SMPS with a lamp while listening if the buzz goes away is just one way of doing it. Shouldnt take too long to try it...
Thanks for the info about grounding. I have meanwelled my ACA, also have earth sound problems. Now have a path to investigate. I thought to dissect all connections in out, but this is easier 🙂
Why not just use a filter for a car? If it'll filter a noise alternator, the Meanwell should be easy.
https://www.amazon.ca/Install-Bay-I...fcdcf&pd_rd_wg=J3az9&pd_rd_i=B00691PFN6&psc=1
https://www.amazon.ca/Install-Bay-I...fcdcf&pd_rd_wg=J3az9&pd_rd_i=B00691PFN6&psc=1