Gday guys,
May I please ask for some opinions.
I would like a dual channel variable power supply. Mostly for initial testing of projects.
I already have a 0-18vdc single channel supply.
I would like to have the flexibility of up to say +/- 60vdc for testing things like a future wolverine build.
I could fairly easily make a variable regulated supply for +/-25vdc or so /1.5a. Not much use for testing power amps though. A very cheap option but limited in usefulness to smaller amps and linestage type things.
I could plausibly, with a lot of work make a +/- 60vdc regulated supply but this wouldn't be easy nor cheap.
I could buy a variable supply such as the nicepower sps605-2kd 2x60v @ 5a. Which does most everything one might want for circa $300.
Or for similar money I could buy a variac and cobble together some spare parts and meters to make a variable linear supply with the added bonus of being able to test 'finished' amps as well as modules.
Should I just grab the variac?
May I please ask for some opinions.
I would like a dual channel variable power supply. Mostly for initial testing of projects.
I already have a 0-18vdc single channel supply.
I would like to have the flexibility of up to say +/- 60vdc for testing things like a future wolverine build.
I could fairly easily make a variable regulated supply for +/-25vdc or so /1.5a. Not much use for testing power amps though. A very cheap option but limited in usefulness to smaller amps and linestage type things.
I could plausibly, with a lot of work make a +/- 60vdc regulated supply but this wouldn't be easy nor cheap.
I could buy a variable supply such as the nicepower sps605-2kd 2x60v @ 5a. Which does most everything one might want for circa $300.
Or for similar money I could buy a variac and cobble together some spare parts and meters to make a variable linear supply with the added bonus of being able to test 'finished' amps as well as modules.
Should I just grab the variac?
Not that I'm necessarily a huge fan of Amazon, but this shows the single channel dual output sps605 for 70- usd:
https://www.amazon.com/Variable-4Digital-Adjustable-Regulated-Switching/dp/B08FT18FQL
You could get two of them new for 140-, and a used Variac off of eg Ebay. There might be an operation mode that the -2kd has that could be useful, of course.
I have a variac and an ancient bench supply already, but want (like you) something more modern and +-60v capable.
https://www.amazon.com/Variable-4Digital-Adjustable-Regulated-Switching/dp/B08FT18FQL
You could get two of them new for 140-, and a used Variac off of eg Ebay. There might be an operation mode that the -2kd has that could be useful, of course.
I have a variac and an ancient bench supply already, but want (like you) something more modern and +-60v capable.
It's not obvious to me that the single supply ones can be run in series for a bipolar supply. I can't find anything in the documentation.
Do you think there is much point paying extra for a 1kva variac over a standard 500va?
Seems like there isn't to me as the purpose is fault finding.
I'm bleary eyed from lack of sleep but isn't the non-2kd sps605 bipolar? I can't find a link to the manual. It has + and - outputs and ground, but I can't see whether it splits the total voltage output in half. If that's the case, they have a 120v model for a little more dough.
I did try their "Ask Rufus" feature but he didn't know. I probably need to reword my prompt.
I did try their "Ask Rufus" feature but he didn't know. I probably need to reword my prompt.
I would think a 500va would be fine for most use cases. The one I got was at a yard sale, works fine - the circular contact area (where the winding is machined flat and where the brush makes contact) is perfect. These are of old school manufacture, and I've not seen one yet that doesn't look like it would easily last decades 🙂
(edit: 30 minute post editing time expired. https://www.manualslib.com/manual/3286978/Nicepower-R-Sps305.html shows a horizontally oriented model might be available)
(edit: 30 minute post editing time expired. https://www.manualslib.com/manual/3286978/Nicepower-R-Sps305.html shows a horizontally oriented model might be available)
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I am in the same dilemma. Saving up for the RD6006P and RD6012P, mainly because I can use them to build the curve tracer software.
The RD6006P goes to 60v 6 amps, and the RD6012P is also 60v but 12 amps.
Versatility of using them for testing circuits, but also getting sweet transistor curves!
@mbrennwa developed the software.
https://pypsucurvetrace.readthedocs.io/en/latest/PSUs/supported_PSUs.html
The RD6006P goes to 60v 6 amps, and the RD6012P is also 60v but 12 amps.
Versatility of using them for testing circuits, but also getting sweet transistor curves!
@mbrennwa developed the software.
https://pypsucurvetrace.readthedocs.io/en/latest/PSUs/supported_PSUs.html
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I'm just starting to look after years of being happy with what I have, which is very old and bought from Goodwill (still works great - I like to recycle).
I am frankly amazed that we can get stuff like either of the above for the little cash outlay involved. Thanks for the link to pypsucurvetrace, great stuff!
I am frankly amazed that we can get stuff like either of the above for the little cash outlay involved. Thanks for the link to pypsucurvetrace, great stuff!
Yep, I'm looking at my old supply which has separate positive and negative supplies with separate adjustments plus a link function, and a third supply with a limited voltage range which has positive and negative terminals plus ground. I'm sure you're right. Coffee FTW!
I’ve often wished my variac featured a circuit breaker, rather than a fuse. When troubleshooting, one can easily end up replacing a number of fuses. A circuit breaker never has to be replaced.
I'd recommend some off-the shelf adjustable bench supplies. Two in series for bipolar supplies is easy-peasy (I do this often). The big advantage of most bench supplies is that you can set voltage and current limits, which is great to prevent any releases of magic smoke when testing new builds.
I personally like the Korad / RND and Ruiden / Riden units. They are cheap and work well.
I personally like the Korad / RND and Ruiden / Riden units. They are cheap and work well.
Is there a circuit breaker that somehow allows changing of the break point? I can see wanting to change a fuse to a lower rating than the variac itself, in order to protect the device being tested. An adjustable current limiting circuit that trips the breaker, perhaps?
I have an ebay DPH5005 50V/5A out and is buck/boost can be fed with basically any voltage (I use 24Vin).
They have USB/Bluetooth and are compatible with Smuview (Sigrok) so you can control it from your computer.
You could get two of them and power each with an isolated supply and connect them to have +/- rails.
There's plenty case projects for them although I got its metal case:
https://www.printables.com/search/models?ctx=models&q=dph5005
DPS version is not buck/boost like DPH.
Wouldn't say it's the most precise instrument but works fine for a lot of random stuff.
They have USB/Bluetooth and are compatible with Smuview (Sigrok) so you can control it from your computer.
You could get two of them and power each with an isolated supply and connect them to have +/- rails.
There's plenty case projects for them although I got its metal case:
https://www.printables.com/search/models?ctx=models&q=dph5005
DPS version is not buck/boost like DPH.
Wouldn't say it's the most precise instrument but works fine for a lot of random stuff.
Is it confirmed that a pair of these can be stacked in series for a bipolar supply?
I am under the impression that not all such supplies can stacked in series.
I've managed to find a 2kva variac locally for $100 on marketplace.
This opens up option c for me quite nicely. I am dreaming up my dream supply
-DBT in series with the variac with bypass switch
-Standard power outlet for testing finished builds
-Bipolar supply bypass switch for testing finished builds
-Load on/off switch
-Auxilary dc supply so that I can use pretty digital meters
-AC volt/current meters after the variac
-DC volt/current meters at the output
-Fuses and main power switch not shown.
Aside from the meters and the variac. I should be able to cobble this together with stuff in have in the junk box
Salvaged transformers, caps, rectifiers etc from AV receivers.
Salvaged switches from old commercial coffee machines.
etc.
This is probably the way to go.
This opens up option c for me quite nicely. I am dreaming up my dream supply
-DBT in series with the variac with bypass switch
-Standard power outlet for testing finished builds
-Bipolar supply bypass switch for testing finished builds
-Load on/off switch
-Auxilary dc supply so that I can use pretty digital meters
-AC volt/current meters after the variac
-DC volt/current meters at the output
-Fuses and main power switch not shown.
Aside from the meters and the variac. I should be able to cobble this together with stuff in have in the junk box
Salvaged transformers, caps, rectifiers etc from AV receivers.
Salvaged switches from old commercial coffee machines.
etc.
This is probably the way to go.
If they have isolated input then sure. I used mine as a negative voltage supply a few times. Not sure about laptop bricks (as input) but I used a transformer with a bridge and a cap and worked fine.