Bench power supplies

[jasonbay13]

I am looking for a bench power supply. finally got tired of trying to find the right battery, wall plug, chinese buck or boost board to just get some volts and amps.

i was looking at the BK Precision 1685B 60V as it has a fairly high voltage up to 5 amps, which should be enough for most things.
it says it can be hooked to pc for logging and control too.
the spec says voltage regulation to 50mv, which is good. but the current regulation is only 100ma? seems a bit inaccurate for something so costly?

what would be wrong with something affordable such as the ebay eBay auction: #http://www.ebay.com/itm/Wanptek-KPS305D-0-30V-0-5A-Adjustable-Digital-Switching-DC-Power-Supply-110-220V/371747815944?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D2%26asc%3D39107%26meid%3D7fce72f723b24080b1947f41d518c21e%26pid%3D100005%26rk%3D5%26rkt%3D6%26sd%3D381030711964

looking for suggestions, thoughts. i'd like to have something around the 60v range with cv/cc and cheaper is better, as always

p.s. first post here (though not the first time i was mentioned here...), hi all!

[MarkF]

How much do you want to spend?

I have a few HP2616A supplies from eBay for less than $60 including shipping. I really like their small size. You can hook multiple units in parallel or serial.

For most projects, 30V should be more than enough. I'm also looking at the new Rigol DP711 supply for a little more current. Which I only would have liked to have for one project.

[jasonbay13]

i like the looks of that rigol, except that i mess with leds sometimes and they often have Vf around 34v.
tad bit pricy, too. i'd like to spend no more than $250, and even then i'd prefer around $100.

currently the best "bench supply" i got is an atx psu with a lm317 and centech dmm hooked up to it for a max of 14v and not a lot of power, esp. with the small heatsink i got  on it.

i was thinking about just winding my own transformer for 40v dc to a 317 driving a 2n3055 with a gigantic heatsink. but run into the problem of current control. and even if i can, whats my accuracy? 200ma/mv? at best?

[Cody Turner OKC]

I just got my first bench psu its a Bk precision 1735A and its 0-30v and 0-3A, honestly i thought i would need double volt and amps before! Now i realise i could get by with half of it, mine doesnt hook to the computer it had some minor problems i troubleshooted and got help on here and fixed within a day. All in all its a nice supply only complaint i have is the course and fine adjustments, the course is way to course,  and the fine is okay but only covers about 40mv/ma. Its nice to have the constant current and the current limiting once you figure it all out,  just giving a little intel on my thoughts of the BK around the same model! Hope it helps a little bit!

[MarkF]

If you had two HP2616 supplies, you can put them in series to obtain +50V or +/-25V. The only draw back is that they only have a 400mA output (which can be doubled if you put two units in parallel).

Also, the Tekpower TP3005T maybe an option.

[ez24]

If you like Art Deco

http://www.ebay.com/itm/Lab-Power-Supply-3-Outputs-2x-0-32V-1A-0-15V-2-5A-Works-Great-US-Made-/172323366754?hash=item281f45e762:g:4IAAAOSw3xJXo5Nv

Power Designs Power Supplies are highly respected on this forum.  Some members restore them.  A lot better than new crap.
There are a million posts on them here.  They are a work of art.

Another idea - place a WTB post here, I bet you could find some good finds here

[julian1]

Don't overlook the value of a dual rail supply (or two single supplies) - if you're going to play around with op-amps or audio amplifiers etc.

And 60V at 5 amps is a really big! It's easy to see the design trade-offs involved with the 100mA OC resolution - making it a lot less useful for smaller electronics work.

I wonder if you could get away with a more general-purpose supply - and then jury-rig something for the high-voltage stuff (custom secondary winding on a toroid + regulator + filter cap).

[mtdoc]

For 60V and 5A on a budget, it's hard to beat the Mastech HY3005 supplies on eBay which can be found for about $200.

They give you dual 30V 5A supplies that can be put in series or parallel with a button to give you either 60V 5A or 30V 10A.  They also have a 3rd fixed 5V supply.  You'll find them under different branding sometimes but they all have the same look - though some have LED displays and some have LCD. Build quality is reasonable for the price but they are not "precision" power supplies by any means.  You'll want to use a multimeter to adjust output if you need precision.

Here's one under the "Dr. Meter" label on eBay for $196 with free shipping.

[NottheDan]

I just had a linear 305 arriving here yesterday. Working pretty well and it is good enough for my purposes but the lack of control and feedback in the very low current range is a definite annoyance. You also have to keep in mind the switching spikes.

[ProBang2]

What´s about the Korad KA 6005 (D or P)? Not available in the USA?

[bitseeker]

Power Designs Power Supplies are highly respected on this forum.  Some members restore them.  A lot better than new crap.
There are a million posts on them here.  They are a work of art.

Yeah, Power Designs made quite a lot of models including some precision ones. Note that some models have constant current operation whereas others only offer current limiting (disables output when limit exceeded).

(Un)fortunately, they're kind of addictive. I just added one of these to my collection. 20V, 1.5A, CV and CC, plus etched panel lettering rather than less-durable silkscreen type. Only 150uV ripple.

[Savetheday]

I think everyone should have one pc power supply converted branch Power supply like that



or
 
something more professional




Good Luck!!

[ez24]

(Un)fortunately, they're kind of addictive.

This is the only downside to them.  They are just soo pretty.

[jasonbay13]

https://www.amazon.com/gp/aw/d/B00G0HAY3U/ref=mp_s_a_1_5?ie=UTF8&qid=1479769537&sr=8-5&pi=AC_SX236_SY340_FMwebp_QL65&keywords=Korad+Technology&dpPl=1&dpID=41ozOi8%2BkeL&ref=plSrch

i can see that. 10mv and 1ma accuracy. exactly what i want except lacking pc co trol, which i cant find anywhere.
assuming it doesnt blow up like the 3005p did for dave, i think thats would be perfect.

p.sp.s. spell check on phpne is imlossi le.

[bitseeker]

For the programmable version, the KA6005P is pretty scarce. The KA6003P is more readily available if you can live with 3A. However, for more flexibility you could get the KA3305P triple-channel power supply and still achieve 60V 5A by configuring channels 1 and 2 in serial. If I had to choose between a KA3305P and a KA6005P, I'd get the KA3305P.

http://www.sra-solder.com/korad-ka3305p-programmable-precision-variable-adjustable-30v-5a-dc-triple-linear-power-supply-digital-regulated-lab-grade

[ProBang2]

I support the recommendation of bitseeker.

If in budget, then go with the KA3305P. It´s much more versatile. 
It is probably the best bang per buck PSU at this time.
One step up - and you are in the area of the Rigol or Siglent PSUs (with twice the price).
One step down - and you are loosing resolution and functionality (in worst case with an overpriced cheapo).

I use a KA3005P since May 2015. (Yes, the same model that is blown up in Dave´s video. But that is
a story long time ago, in a country far far away... They had made some board revisions since then and there
are follow-up videos. So this story is like  )

My experience with this device is good. It has for sure no easy life. Sometimes abused for automotive use (e.g.
to load a car battery with 14.8V @ 5A over 24h or to search a randomly occuring short circuit), then used
for electronics, the output limited to just a few mA. It works well.

Unfortunately I have no experience with the KA3305P. The lack of negative threads in this forum should be
a good sign. Hence I will probably buy one in the next future.

[jasonbay13]

Gonna grab the ka3305p as it seems to have the functionality i need at a not-completely-bankrupting price.

should i let you know what i think of it as a beginner with no previous supplies to compare it against?

[bitseeker]

Of course! Photos of the insides are always welcome, too, if you're feeling mischievous. Otherwise, don't jeopardize your warranty.

[jasonbay13]

Got it in the mail today. messing with the settings still, but thought i'd let you know about first impressions.
the layout and display seem pretty nice. all 5 memory buttons retain memory, but either keeps what was last used on that memory slot, or can only store after being set while on it.
accuracy is well enough. i was seeing variation +- ~4mv between single volt increments, have not checked cc accuracy.
heavy unit, rather deep too and fits perfectly on my bench.

voltage and current control is kinda awkward since you have buttons for ch1 or ch2 each switches between the ch's voltage or current to use with the two knobs, which is voltage on left knob and current on right knob. but if you have ch 1 voltage blinking and try using the current control, it wont work until you either push ch 1 again to get current or push the current knob, which makes me wonder why there are two wheels when only one is needed.

this is about 15 minutes into playing with it...

pictures of insides might happen someday but first i really need to prioritizing on getting rid of some stuff. *smalltext* i'mnotahoarder *smalltext*

[jasonbay13]

it seems i've run into a problem, not sure if it is something i did but in M1 i cannot lower the current value for ch2. i can make it higher but not lower. ch1 works normally. and if i set it to serial or parallel i can lower it on ch2. M2 works fine.

[bitseeker]

it seems i've run into a problem, not sure if it is something i did but in M1 i cannot lower the current value for ch2. i can make it higher but not lower. ch1 works normally. and if i set it to serial or parallel i can lower it on ch2. M2 works fine.

I'm not sure I follow. Are you saying that you cannot store into memory location M1 a current value for Ch2 that's lower than the one that's already stored there?

When set to serial or parallel, which channel is master, 1 or 2?

[jasonbay13]

when i have the supply on M1 preset i can change the voltage and current up AND down for channel 1, but channel 2 only allows me to change voltage up and down and current up but NOT down.

i can turn the wheel up, and it increases, turn the wheel down and nothing happens. though it does keep the display in set mode (blinking) as if i were actually adjusting it. all the other M2-M5 work as expected.


i can get it to go back down by using serial/parallel, unsure as to which is slave/master.

[Aeternam]

First make sure you're not in serial or parallel mode.

Then try changing the voltage on CH2, then change the current setting. That should help. This is a weird interface bug I experienced once or twice; I can't remember what I did to regain control of the current setting but I'm pretty sure it involved fiddling with the voltage setting.

[jasonbay13]

I went to take a video, so I set up M1 and M5 for some leds to demonstrate, but ended up somehow transferring the problem from M1 to M5. Then after a little bit more messing with the knobs and buttons the problem went away completely.

I think it might have something to do with switching between M1-M5 while the selection is still blinking (in set mode)

[xani]

I've got  KORAD KA3005D-3S (dual 30V/5A with serial/parallel mode + constant 5V/3A)  some time ago and I'm very happy with it (only problem was a bit shoddy power switch but that is easy enough to replace), but it seems it is not available anymore? Did they stopped producing it ?

Current limit goes down to few mAs which is very nice as that already saved one board from releasing some smoke