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Adjustable Output Power Supply

HighTechLab

AKA Dexter - CTO of Current Connected, LLC
Joined
Sep 23, 2019
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So I've been looking for a power supply that I can use in my lab for charging batteries and such somewhat precisely...Desirable features are adjustable current output and adjustable constant voltage output.

I would probably want somewhere from 10-60 volts and 0-30 amps, the higher the output wattage the better and I do have 240v outlets in the lab I can throw at it.

Does anyone have any recommendations? My budget is somewhere in the $400 range.

This would be used for charging up different array configurations of batteries, e.g. 12v, 24v, 48v, with different chemist
 
For that kind of flexibility I have gone for the used Sorensens on ebay. I assume in the range you mention you are not intending to get 30a @ 60v? If so that might be a tall order in your price range. Used benchtops can be a gamble. I've purchased two; the first was bad, the second has given me years of service. I linked an example of the kind of Sorensens I'm talking about, the slim ones. They are light and compact and much easier to return if DOA. My slim one is the one that works. The big 150 pounder is the one that did not, lol. This is not quite in your current window but may do in a pinch [you can probably find one closer to your budget too]: bench pwr supply


Since you are talking adj. power, I gotta sneak this in here. I've considered posting about it because it is such a gem and I have not really found anything quite compared to it in that price range: ABB

And one last one, if you haven't checked out the powerlab8, it's the most flexible charger I've come across, albeit it's for the rc market: powerlab8
 
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For that kind of flexibility I have gone for the used Sorensens on ebay. I assume in the range you mention you are not intending to get 30a @ 60v? If so that might be a tall order in your price range. Used benchtops can be a gamble. I've purchased two; the first was bad, the second has given me years of service. I linked an example of the kind of Sorensens I'm talking about, the slim ones. They are light and compact and much easier to return if DOA. My slim one is the one that works. The big 150 pounder is the one that did not, lol. This is not quite in your current window but may do in a pinch [you can probably find one closer to your budget too]: bench pwr supply


Since you are talking adj. power, I gotta sneak this in here. I've considered posting about it because it is such a gem and I have not really found anything quite compared to it in that price range: ABB

And one last one, if you haven't checked out the powerlab8, it's the most flexible charger I've come across, albeit it's for the rc market: powerlab8

Seems like some really good options here, is the one that is a rack mount system able to be paralleled for more charging current? I'm mainly trying to bulk charge batteries quickly for capacity tests.
 
I wish I had a better answer for you about parallel Sorensens. I know that some of them can be but not sure which ones. The thing with those units is that they are industrial quality gear, which is the only thing that I will buy used. The thing to do if you pick up a used supply like that is to first check if you can get an operator manual online. Any Sorensen I have ever considered for purchase, I was able to track down a manual for. IMO if you cannot find a manual it's a deal breaker, unless you are getting a super deal for a known working unit that has a return policy. Either way, don't buy one you can't send back.

You definitely need a manual with the one that I posted from ebay. Its similar to mine and the current adjustment is not straight forward as it looks on the controller. You can't just turn the current up, you have to turn the knobs in a certain sequence to switch over from voltage mode to current mode. I had to dig into the spec to figure mine out. But I vaguely recall something about parallel config in one of the manuals, but I cannot say for sure which model has it.

The Powerlab8 is just an 8s charger that will charge at 1000w. You will need a dc power supply to run it at I think 12-24 volts. You need the full 24v (or whatever the max input is) to get the max charge rate. That unit is not exactly what you are looking for but it is most definitely parallelable. You can sink them together and run them on you pc for more control. They also have a pretty powerful discharge capability too. You wont be getting 60v out of one though, just the 8s voltage. And I think it's just parallel config. not series, so that won't get you there either. Also, these require some serious operator's manual study. I still haven't completely wrapped my head around some of the features lol. I'm not as versed on the charger options in the solar sphere, so for the higher current I'm just going to assume there are plenty of better scenarios. For absolute control of a cell however, the powerlab seems to be top tier. For general AC to DC power the stuff from Meanwell is hard to beat. I have a 1600w Meanwell RSP 1600-24 to run my Powerlab. I guess you might consider everything I have mentioned to be alternatives to whatever is hot right now in the solar world. But for bench type stuff like your talking about, they may be relevant, or at least good to know about.

Just checked the Revolectrix site and it looks like they now have a dual 8s 2700w version too: dual pwrLab Cheers-
 

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So I've been looking for a power supply that I can use in my lab for charging batteries and such somewhat precisely...Desirable features are adjustable current output and adjustable constant voltage output.

I would probably want somewhere from 10-60 volts and 0-30 amps, the higher the output wattage the better and I do have 240v outlets in the lab I can throw at it.

Does anyone have any recommendations? My budget is somewhere in the $400 range.

This would be used for charging up different array configurations of batteries, e.g. 12v, 24v, 48v, with different chemist
So I have one of these https://www.amazon.com/TekPower-TP1...ng-Digital/dp/B015RXDRE0?ref_=ast_bbp_dp&th=1

problems is fine tuning is only .1 Volts and it is easy to accidentally hit knob and turn volts too high or low.

I also use these they are cheesy but work very well I parallel 3 of them but don't see why you couldn't do more.

https://www.amazon.com/Converter-DR...ld=1&keywords=drok+mppt&qid=1586556450&sr=8-2
 
I picked up a used Philips (nee Fluke) PM2811 for $80 on eBay from these guys:
1586697009093.png

Ad claimed all it needed was a fan replacement. Another $15 bucks and I now have a pretty sweet adjustable/programmable (CV, CC) linear power supply (for under $100):
1586697407848.png

Once the new fan was in, tested it before using it to top balance my new LFPs (16P). (Pic above was first test on some rechargeable AA cells I had laying around).

Have discovered that I can live w 60W overall. I just program it to increment the voltage in successive CV/CC steps to stay under that # if I need to. Overall lower C rate than you would get from something bigger/more expensive, but it does the job quite nicely if you don't need more than 30V.

You can also daisy chain these guys for more if you need more watts (or look for a PM2812 or 13). National has quite a bit of rental stock they sell, so you may find another there that better matches your needs. They did seem to have the best deals of all the other test equipment outfits I searched and their packaging is top notch, encased in 2 form-fitted foam pieces, top and bottom.
 
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I was looking at this one, pretty powerful unit, but the biggest downside is it requires 3 phase power. My shop doesn't have 3 phase and it would be super ineffecient to run a rotary converter.
 
Here's the thing that has always amused me. We spend so much time trying to find an APS to initially balance and capacity test our new cells but most of us who are doing this HAVE a DC power supply (our panels) and balancing/monitoring/logging product(s) with built in HVC and LVC (our BMS/SCC's). These could actually do the capacity test as well without any additional effort or cost. And no babysitting (w properly config'd cutoffs). Would be nice if BMSs were able to balance at higher currents for this (an initial balancing mode?).

It's especially amusing that once we're done with this task, many of us have no more need for the APS. It's one and done.

My BMS could probably do this if I tweaked some parameters but I want to get some time under my belt with just the default settings before diving into the advanced ones. Plus, it's limited to 200mA balancing current (albeit on the way up and down). Just seems like a niche that wouldn't be too hard to fill with only slightly more effort.

Am I missing something?
 
Here's the thing that has always amused me. We spend so much time trying to find an APS to initially balance and capacity test our new cells but most of us who are doing this HAVE a DC power supply (our panels) and balancing/monitoring/logging product(s) with built in HVC and LVC (our BMS/SCC's). These could actually do the capacity test as well without any additional effort or cost. And no babysitting (w properly config'd cutoffs). Would be nice if BMSs were able to balance at higher currents for this (an initial balancing mode?).

It's especially amusing that once we're done with this task, many of us have no more need for the APS. It's one and done.

My BMS could probably do this if I tweaked some parameters but I want to get some time under my belt with just the default settings before diving into the advanced ones. Plus, it's limited to 200mA balancing current (albeit on the way up and down). Just seems like a niche that wouldn't be too hard to fill with only slightly more effort.

Am I missing something?
Acually, now that I've reread what I just wrote, what I'm describing is an active balancer (?) Maybe not.
 
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I was looking at this one, pretty powerful unit, but the biggest downside is it requires 3 phase power. My shop doesn't have 3 phase and it would be super ineffecient to run a rotary converter.
Since you went and doubled your budget ?, this might do unless that last five volts are a deal breaker DC55-55. I think I saw another version that was 80v 40a for under 1k$ as well, not sure if 1ph though.
 
Here's the thing that has always amused me. We spend so much time trying to find an APS to initially balance and capacity test our new cells but most of us who are doing this HAVE a DC power supply (our panels) and balancing/monitoring/logging product(s) with built in HVC and LVC (our BMS/SCC's). These could actually do the capacity test as well without any additional effort or cost. And no babysitting (w properly config'd cutoffs). Would be nice if BMSs were able to balance at higher currents for this (an initial balancing mode?).

It's especially amusing that once we're done with this task, many of us have no more need for the APS. It's one and done.

My BMS could probably do this if I tweaked some parameters but I want to get some time under my belt with just the default settings before diving into the advanced ones. Plus, it's limited to 200mA balancing current (albeit on the way up and down). Just seems like a niche that wouldn't be too hard to fill with only slightly more effort.

Am I missing something?
I agree with all of these sentiments except that my preference is the exact opposite. I would rather ditch as much specialized battery/solar specific equipment as possible and have more generalized industrial/laboratory grade hardware. Much easier to re-purpose lab gear to do any number of things, on the fly, than it is to try and re-purpose a bunch of specialized equipment. Industrial pwr supply with some cheap expandable bms would be nice; throw a charge controller in the middle if necessary. Of all of those, the power supply is the only absolute necessity and going with the big guns will allow for highest level of flexibility. General Purpose + maxed out quality, which usually means going used. And then go make friends with the local electronic repair shop, lol.
 
I agree with all of these sentiments except that my preference is the exact opposite. I would rather ditch as much specialized battery/solar specific equipment as possible and have more generalized industrial/laboratory grade hardware. Much easier to re-purpose lab gear to do any number of things, on the fly, than it is to try and re-purpose a bunch of specialized equipment. Industrial pwr supply with some cheap expandable bms would be nice; throw a charge controller in the middle if necessary. Of all of those, the power supply is the only absolute necessity and going with the big guns will allow for highest level of flexibility. General Purpose + maxed out quality, which usually means going used. And then go make friends with the local electronic repair shop, lol.

And that's how I roll - I don't like the cheap hack-job type of stuff. Especially with my YouTube channel, I want to make sure the information I give viewers is based on trustable lab-grade equpiment, not some cheap inaccurate meter off of amazon that has a 2% inaccuracy.

That's why (almost - I have one klein clamp amp meter) all my meters are fluke brand. I don't intend to only use this power supply once - I have thoughts on business plans that could easily make use of a precision APS on a daily basis.

And I think I just solved the 3 phase issue/idea based on business location....HMM
 
And that's how I roll - I don't like the cheap hack-job type of stuff. Especially with my YouTube channel, I want to make sure the information I give viewers is based on trustable lab-grade equpiment, not some cheap inaccurate meter off of amazon that has a 2% inaccuracy.

That's why (almost - I have one klein clamp amp meter) all my meters are fluke brand. I don't intend to only use this power supply once - I have thoughts on business plans that could easily make use of a precision APS on a daily basis.

And I think I just solved the 3 phase issue/idea based on business location....HMM
If you go high-end industrial, used, and get burned 50% of the time, you will still come out on top. All high-end is worth repair. It is also worth learning the gory details to handle issues on your own to save a buck. It's hard to justify taking the time to learn about electronics if it's just as well to toss something and replace it. The problem doing that is your potential ceiling is at half (or probably much less) the height of getting into used industrial. One thing I never hear mentioned when weighing quality options is the x factor of troubleshooting a project failure. If you are doing an experiment and something does not work according to plan, you are then faced with questions like "did it fail because of this or this piece of gear?" and with mid-tier that question becomes a lot bigger. If something goes wrong and it's with industrial grade hardware you are not faced with those types of what ifs. Either your equipment failed and needs to be repaired, or you did not apply it to the right application. It's never a question of whether what you have is just not up to task because, quality.
One the 3ph issue, to my mind the efficiency drop is less an issue than dealing with the major annoyance/inconvenience of having to go turn one on every time you need it. And you definitely don't want to just leave it on if not in use. For your application maybe one of those digital units would do the job. Depending on how much power you need they can be pretty reasonable. I have a Phoenix rotary 40hp that was like 1800$ new iirc. I bet you could pick up a starter/controller for say 15hp and then score a nice used motor elsewhere and get it done on the cheap. Hell, just build one! A bunch of caps wired so you can tune them , a mag contact, and a switch, that's about it. That alone would make some sweet content for the tubes.
 
I agree with all of these sentiments except that my preference is the exact opposite. I would rather ditch as much specialized battery/solar specific equipment as possible and have more generalized industrial/laboratory grade hardware. Much easier to re-purpose lab gear to do any number of things, on the fly, than it is to try and re-purpose a bunch of specialized equipment. Industrial pwr supply with some cheap expandable bms would be nice; throw a charge controller in the middle if necessary. Of all of those, the power supply is the only absolute necessity and going with the big guns will allow for highest level of flexibility. General Purpose + maxed out quality, which usually means going used. And then go make friends with the local electronic repair shop, lol.
I agree and disagree. Agree that lab grade gear is better, esp when it comes to power supplies. Will's experience w cheap versions of these seem to be the rule not the exception and why I steered clear of 'em. The DIY solar gear, for the most part however, seems up to the task of what people need it to do, with the exception of the initial balancing/capacity testing. I think the reason folks opt for the cheaper APSs is that it's hard for them to justify the expense for something they're not going to use over and over, with the result that what they get is more troublesome than what their SCC/BMS set up does on a daily basis all by itself, just at a lower amperage.
 
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I agree and disagree. Agree that lab grade gear is better, esp when it comes to power supplies. Will's experience w cheap versions of these seem to be the rule not the exception and why I steered clear of 'em. The DIY solar gear, for the most part however, seems up to the task of what people need it to do, with the exception of the initial balancing/capacity testing. I think the reason folks opt for the cheaper APSs is that it's hard for them to justify the expense for something they're not going to use over and over, with the result that what they get is more troublesome than what their SCC set up does on a daily basis all by itself, just at a lower amperage.
Definitely no arguments. Just different strategies; one is efficient for a specific job, the other for general flexibility/reliability.
 
Yeah, I think you two are in a different league. :rolleyes:
Think of it like this, you probably are not loosing sleep over trying to maintain equipment assets while keeping Visa at bay o_O. Personally I live in a 20ft^2 corner of my shop just so I can play with bigger tools. I have to duck under a VMC console just to depart the loveseat I've been sleeping on for the last three years!

20200413_150502.jpg
 
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Think of it like this, you probably are not loosing sleep over trying to maintain equipment assets while keeping Visa at bay o_O. Personally I live in a 20ft^2 corner of my shop just so I can play with bigger tools. I have to duck under a VMC console just to leave to depart the loveseat I've been sleeping on for the last three years!

View attachment 10936
Jeez. Looks like you got a Manhattan Project going on in there. Like I said ...
Yeah, I think you two are in a different league. :rolleyes:
 
what do you guys think about the quality of this unit http://mastechpowersupply.com/programmable-dc-power-supply-hy1550ep-0-15v-0-50a.html
I know it is not the voltage you need but it will work fine for charging my batteries for testing
At that discounted price it seems reasonable. Those adjustable controllers on amazon you found look like they'd be fun to run with an arduino, too. But to have one integrated like that would sure save a lot of tinkering around, plus not needing a supply source. The quality issue is kind of hard to say, but it's probably good to go. Alternatively you can tell by what the market is for a used one. Like in the audio market, you can pick up a new Rotel amp and still fetch top dollar if you sell it in five years. Or you can pick up a used Rotel and still be able to flip it five years from now and either break even or even turn a small profit, or take a small loss. In the context on those industrial power units the situation is similarly like trying score a 5k$ supply for 500-1K$. The goal is to find normally unaffordable equipment at 1/2 all the way to 1/10 of the price, thanks to liquidation- etc, and has a thriving used market.
 
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