Testing my power supply with Oscilloscope

[RissViss]

Was watching this video.


In the picture below, the larger laptop power brick is my power source for the DP30V5A DC to DC converter.
From the brick I am getting a ground so that the metal case is grounded, the front lower left black binding post is on the same ground.
From the video Dave was taking about using brick power supplies that have a ground, and that the common could be attached to ground. ( trying to say this in a way that will make sense hopefully)
When I check the black ground on the lower right to the common or - below the red binding post my meter reads  .947 K ohms with it powered.

Does this mean that the power supply is not floating?

When I use it to power up circuits where do I put the ground from the Oscilloscope. A. the black ground binding post or the black negative post.

Just built this would like to not blowup my only power supply and Oscilloscope. 

[dcbrown73]

Obviously, you want someone with more experience than me answering this, but I will say this. 

If the binding post is grounded to the PSU's earth ground and you touch both the binding post and the neutral together with continuity tester and it beeps.  Then your neutral is earth grounded.

[RissViss]

Thanks for the reply.

There is no continuity, if I put the meter to buzz, it will not make a buzzing sound on the ground + common.

May just have to hook up the Oscilloscope and see what I get.

Still have to find out if the ground clamp get put on ground or common, or does it not matter.
Would like to know that part.

[StillTrying]

"DP30V5A DC to DC converter."

The input gnd/-ve to them PSU's has to be floating, so that you can safely connect a real earth such as a scope gnd to the output gnd/-ve, so don't connect the brick's -ve side to anything other than the DP30V5A's -ve.
There a few mentions on here. www.eevblog.com/forum/blog/eevblog-1030-$20-diy-bench-power-supply!/msg1319137/#msg1319137

With them both plugged in you could measure between the brick's -ve and the scopes GND clip, you'll hopefully just find a floating voltage but no current.