Power supply ground

[Bamball95]

Hello all, my power supply has a three prong plug. I thought that meant the metal case had to be grounded as well. However, I tested continuity between the ground terminal and the case and I got nothing. Could it be that the case isn't grounded? I did this test with the power supply unplugged.
Thanks guys, Beau

[Al_The_Man]

What make/kind of power supply?
Is this your PC power supply? Or just a stand alone supply?
Normally any metallic chassis should be grounded, including your PC P.S.
Al.

[Bamball95]

Thanks for you reply Al. It is a stand alone power supply. Model number S-348w-24. It looks very similar(but I don't think its the same) as this one. 350W 24V power supply AC/DC Switching PSU products, buy 350W 24V power supply AC/DC Switching PSU products from alibaba.com
Thanks, Beau

[Al_The_Man]

Much of the equipment coming out of China does not conform to N.A. and European standards, although this states CE approved.
Normally this unit would be earth grounded here.
If it is mounted to a grounded chassis it would be one way of grounding it.
Al.

[Bamball95]

Well could I attach a wire from the input ground on the device directly to the metal casing? Or would this be a bad idea (as far as safety?)
Thanks, Beau.

[Al_The_Man]

If by wire from the input ground being the one from your 120vac socket, That should work.
Al.

[UUU]

In the UK, everything has a three-prong plug, even if it doesn't need a ground connection. In some cases the ground prong of the plug is plastic! This is because most sockets have shutters that won't accept a two prong plug. There's a symbol on devices that don't need a ground, that's one square inside another - stands for double-insulated - mind you, when you take the stuff apart it doesn't necessarily look too safe.

[Bamball95]

Sorry guys this one was my fault. I found that my multimeter had a loose wire. I fixed it and found that my power supply is in deed grounded. Sorry for the trouble.
Beau

[ViperTX]

Bamball95....I'm laughting because that is a lame excuse....you should always check the multimeter against some standard....like touching the leads together when checking for continuity.....