Struck a few things out. ^^ ![Tongue :P](https://www.eevblog.com/forum/Smileys/default/xtongue.gif.pagespeed.ic.J5mTe0A2NA.png)
Will check on noise and come back after dispatch deliveries as I have a EMI setup already on the bench.
Encoder increments are successive to the next decimal place and so on and you can select which decimal place you wish to start in.
Plusses you may not have considered
Set and Load measurements displayed.
Sequential channel ON capability.
Some chaps in the US seem to sometimes find the SPD's cheap when previous owners have not set the mains voltage to 110VAC. ![Roll Eyes ::)](https://www.eevblog.com/forum/Smileys/default/rolleyes.gif.pagespeed.ce.XcUK202Yqt.gif)
Hmm... unstriking them out. Sorry but I think they are crap for the price point.
1. Inconvenient form factor -> Not a rack size multiple. So basically you have to piss 4U up the wall in a test fixture which is ridiculous.
https://siglent.co.uk/product/siglent-spd3000x-x-e-d-s-c-rack-mount-kit/ . If you look at the E36100B series from Keysight it's all 2U units 1/4 rack. Same with the larger units - 1/2 rack etc. That's 8 supplies (!!!!) in the same frikking space. C'mon siglent
![Face Palm :palm:](https://www.eevblog.com/forum/Smileys/default/xfacepalm.gif.pagespeed.ic.EBDwh1hCfo.png)
. Plus as always inconvenient handle on the top and too shallow to support other kit.
2. noisy active cooling. Look at the fan grille. That's going to produce noise under load.
3. 100% duty. Yeah I mean 24/7/365 for at least 5 years. Not going to happen.
4. Encoder -> step in, step out. Doesn't matter about the resolution. I'm not wanting a step function here
![Smiley :)](https://www.eevblog.com/forum/Smileys/default/xsmiley.gif.pagespeed.ic.R8GFI-pF6f.png)
Also lets not forget the unforgivable standard of 0.75" pitch banana jacks which didn't happen on the SPD3303X.
As for .... Set and Load measurements displayed...
- Agree with this as a convenience but 90% of the time this is done up front and then the supply is cycled on and off. Changing that regularly past setting the DUT's supply voltage and CC limit is rare. Even when doing circuit development from scratch this is a fire and forget once operation. Output on/off is about all that is required. Usually if you want to look at transient voltages or change something, you sweep it up and down and leave it back at the set point while the power is applied. You also have the problem with non-analogue non-static (i.e. not like the PL series etc) set/run things where the state of the supply is present in volatile memory thus when you power cycle it, what happens? That depends on configuration. As
I've seen before running Cisco stuff before, what is currently the set state isn't necessarily the power up state which can cause all sorts of hell to break loose.
As for ... Sequential channel ON capability.
- I think that's mostly a marketing null. Sequential power application is one thing you're supposed to avoid in failure tolerant systems.
I'm not buying it. It's got too much shiny and not enough engineering in it.
Edit: on EMC, build a 3 stage 100dB or so common base gain stage and I guarantee you that power supply will be one noisy fucker. HP isn’t!