I am wondering how you doing grounding. Connect all grounds to power supply together. I see some connect common to chassis ground so the shielded cable can be grounded. Some people say to do it that way some say not to. Any advice. I have 2 power supply. I don’t know if this is in the right place or not.

If my brain weren’t so fried at this exact moment, I’d make some joke about grounding everything to Y-axis rail, building a Faraday cage around your shop, or maintaining strict ground discipline and separating all of your grounds. (Note, those are all monstrously bad ideas, and should not be implemented except as click-bait for YouTube views.)

I would generally connect all the DC grounds together at the power supply. I would also try not to make any loops (by connecting two grounds far away from the power supply) and I would not connect the DC ground to AC ground except where the PSU does it.

I don’t know where these rules come from. I haven’t thought about it too closely. If you have two DC power supplies, then combining their grounds is probably a good choice (so they don’t end up connecting somewhere that you wouldn’t want the current by accident).

For cables, I’ve always grounded one end, and not the other. Just to avoid loops again.

It honestly doesn’t come up much. So my guess is that it doesn’t matter all that much.

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I got all my grounds in one strip. But I think I’ll hook all the shielded cable ground to chassis ground. Because there is usually a resistance reading checking from dc ground and dc ground that would hold a voltage across. So I’ll connect to chassis for shielded cable’s

On a related note, it is important to make a distinction between input ground and output ground when talking about power supplies. I am using two 24VDC power supplies in series. Thankfully, their outputs are “floating” meaning not grounded to their chassis which IS grounded to the mains ground. If their outputs were grounded to the chassis, then putting them in series would probably electrocute you or at least release some magic smoke.

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Oh yeah, series psus would not work well at all with dc bonded to earth. It’s important to know your end device ground connections too. For example if you mount an sma panel connector mounted to an earth bonded chassis without thought, you may add a ground loop through a sensitive spot (wifi rf section).

There are times when bonding dc to earth is helpful… for example when probing. Dc ground reference is arbitrary, but there’s no absolute reason it cannot be earth. What is important is ensuring singular return paths (no ground loops) by terminating all of your grounds in one spot (star topology). I personally prefer using earth reference, so my probe works without a bit clip.