Confusion around probing isolated circuits. Is this a safe practice?

[AVGresponding]

I'm not sure if this is normal, but I did just notice that my dreaded transient problem where on the lab bench side and not my PCB. I thought I did something wrong and spent so long, but it has a horrible voltage drop/spike when my esp-32 draws current (when I press reset) or does anything fancy. It's good to design a device for the worst case scenario, but at the same time.... I think I might have to start saving for a proper Siglent lab bench, or google around and see if there's cheaper ones... I was gonna buy a ta305 next month to retire my Pinecil and it's super leaky tip (the ground clip exists, but it's cumbersome) and unergonomic design (I love my pinecil, but it's not an amazing all day solder) so I won't have much money left LOL.

I was going to grab the TC22 which is far cheaper, but the leakage etc scared me... even tho I feel like it's probably nothing and fine (And the people online who report leakage are probably not measuring right)

Siglent doesn't seem to update their models often (Their latest refresh, which was my unit took them 7 years!) So i wonder if there'll release a competitor soon....  1200CAD vs 5000CAD is a huge price difference, but that's ignoring the extras the Siglent sds3000x has. I can't afford one anyways /shrug.

Sounds very much like the load regulation of your PSU isn't up to the task. If you can get by with your current soldering solution, I'd suggest prioritising buying a better PSU, possibly a used HPAK one, as they are usually a lot cheaper in North America than Europe. The Siglent 3303 is reliable (barring one well known and easily fixed flaw on earlier versions), the most annoying thing being the spacing of the binding posts.

TEAS is Test Equipment Acquisition Syndrome, my signature provides an example of this...

Lol I relate to this. I wanted a spectronometer sooo bad for a month or two until I gave up and accepted the unkown. I just GOTTA KNOW if my lights are high quality. you can't just... not know right? This is clearly an essential life purchase, right up there with food.

I wonder if the siglents will also cause the arcing and other issues, I think AFAIK 30-300uA is considered "good" leakage? Tho test equipment is probably made to have less.

Better to have it and not need it, than to need it and not have it!

The leakage I measure on my Siglent SPD3303X is around 13.09uAAC, with around 430mVAC open circuit. There's no measurable DC component.

[AmeliaBuns]

I'm not sure if this is normal, but I did just notice that my dreaded transient problem where on the lab bench side and not my PCB. I thought I did something wrong and spent so long, but it has a horrible voltage drop/spike when my esp-32 draws current (when I press reset) or does anything fancy. It's good to design a device for the worst case scenario, but at the same time.... I think I might have to start saving for a proper Siglent lab bench, or google around and see if there's cheaper ones... I was gonna buy a ta305 next month to retire my Pinecil and it's super leaky tip (the ground clip exists, but it's cumbersome) and unergonomic design (I love my pinecil, but it's not an amazing all day solder) so I won't have much money left LOL.

I was going to grab the TC22 which is far cheaper, but the leakage etc scared me... even tho I feel like it's probably nothing and fine (And the people online who report leakage are probably not measuring right)

Siglent doesn't seem to update their models often (Their latest refresh, which was my unit took them 7 years!) So i wonder if there'll release a competitor soon....  1200CAD vs 5000CAD is a huge price difference, but that's ignoring the extras the Siglent sds3000x has. I can't afford one anyways /shrug.

Sounds very much like the load regulation of your PSU isn't up to the task. If you can get by with your current soldering solution, I'd suggest prioritising buying a better PSU, possibly a used HPAK one, as they are usually a lot cheaper in North America than Europe. The Siglent 3303 is reliable (barring one well known and easily fixed flaw on earlier versions), the most annoying thing being the spacing of the binding posts.

TEAS is Test Equipment Acquisition Syndrome, my signature provides an example of this...

Lol I relate to this. I wanted a spectronometer sooo bad for a month or two until I gave up and accepted the unkown. I just GOTTA KNOW if my lights are high quality. you can't just... not know right? This is clearly an essential life purchase, right up there with food.

I wonder if the siglents will also cause the arcing and other issues, I think AFAIK 30-300uA is considered "good" leakage? Tho test equipment is probably made to have less.

Better to have it and not need it, than to need it and not have it!

The leakage I measure on my Siglent SPD3303X is around 13.09uAAC, with around 430mVAC open circuit. There's no measurable DC component.

Oh nice! that one's 650CAD 0_0. not terribly insanely expensive but not a cheap regular purchase either. could save for  one. That's very low. I assume you can just probe anywhere without grounding it  or worrying?
I  feel very sad when I buy stuff and don't use it often. Almost like they  get lonely, not to mention i'm broke, so for me, I rather not have it but feel the need a few times I might just start saving for one. I've wanted the TA305 for more than a year now tho so if I se a good cupon on aliexpress I'll start with that still.
Funny just during this post I've felt the need for a nicer PSU like 2-3 times. Right now I was trying to test this LED and it only goes up to 31v, I need 36V 

[tautech]

The lower res SPD3303X-E is a bit cheaper and uses the same HW.
Both X and X-E can Series or Parallel 2 outputs for 60V 3A or 30V 6A and multiple units can be placed in series and in Series mode for elevated voltages.

A useful very low noise and totally isolated PSU.

[AVGresponding]

Oh nice! that one's 650CAD 0_0. not terribly insanely expensive but not a cheap regular purchase either. could save for  one. That's very low. I assume you can just probe anywhere without grounding it  or worrying?
I  feel very sad when I buy stuff and don't use it often. Almost like they  get lonely, not to mention i'm broke, so for me, I rather not have it but feel the need a few times I might just start saving for one. I've wanted the TA305 for more than a year now tho so if I se a good cupon on aliexpress I'll start with that still.
Funny just during this post I've felt the need for a nicer PSU like 2-3 times. Right now I was trying to test this LED and it only goes up to 31v, I need 36V

The lower res SPD3303X-E is a bit cheaper and uses the same HW.
Both X and X-E can Series or Parallel 2 outputs for 60V 3A or 30V 6A and multiple units can be placed in series and in Series mode for elevated voltages.

A useful very low noise and totally isolated PSU.

Yeah, mine was an ex-demo RS Pro branded 3303X-E, HW version 3.0, which I re-flashed to Siglent 3303X v1.01.01.02.05 FW, to get the extra digit of resolution. I paid around £120 iirc. It's my daily driver PSU, so I can save the VFDs of my HP6633B and Agilent 66311D   

It's properly floated, so I don't have to worry about grounding; I use the front panel GND post for my anti-static wriststrap...