Korad KA3005P power supply: UI changes

[5U4GB]

The KKG305P is a complete new and different device (even a KD3005 is not comparable to the KA3005) and it's definitely worth a new thread here.

It also seems to be practically nonexistent, Botland.de has it and that's about it, and of their range the 305P model is marked as EOL.  Also from one of the very few discussions of it it essentially looks like a fixed KA/D3005 rather than a new product, e.g. the annoying adjustment-lock is removable as with newer-FW 3005s, the memory-overwrite is fixed as with newer-FW 3005s... it looks like the KKG305s are just 3005s with window dressing, so this is probably the best place to discuss them, because they seem to be just 3005s with UI fixes.

[5U4GB]

Significant improvement: A short press of the "Lock" button enters a mode where you can adjust voltage or current via the encoder and arrow buttons without any timeout. There were many complaints about the short timeout in earlier versions. To lock and unlock the keypad, a long press on Lock is needed.

Just found where I'd seen this earlier right at the start of the thread, this change doesn't seem to have made it into the currently-shipping KA3005D yet, it still has the annoying short timeout where you keep having to press the Volt/Amp button every single time you make a change  Wanted to test the power consumption and light output of a 24V LED strip at lower voltages and every 1V step required re-enabling changes again, grrr.

[Pfriemler]

Just found where I'd seen this earlier right at the start of the thread, this change doesn't seem to have made it into the currently-shipping KA3005D yet...

It would not suprise me if there are still "old" versions in stock to sold as new after two years. On the other hand, we still have no other versions than the Welectron KA3005P+ series proved with the newer firmware. I couldn't believe that KORAD did some changes only for Welectron while still deliverung "old versions" to the rest of the world.

[5U4GB]

The one I got was dated December 2022, 1 1/2 years after the post describing the change, so it's probably not just a supply-chain issue.

Does anyone who has a KKG-series one want to post photos of the insides?  For that matter, does anyone actually have a KKG?  From this Korad catalogue posted to the mikrocontroller.net forums they have a pretty confusing variety of models allegedly out there now.

[littleboot]

instead of a custom temperature fan controller, I bought a PWM fan controller on Aliexpress:
Search for "12V PWM fan controller"
https://vi.aliexpress.com/item/32973504131.html
Prices fluctuate a lot, the one I ordered was €2.79 delivered
Operating instruction of this thing are very badly described, I found this video explaining how to change the temperate and fan settings:


and a thin 80mm fan:
https://vi.aliexpress.com/item/1005005952005094.html
NO-8010-PWM-BLACK
€4.75 delivered

Thin was not required but I wanted a branded fan (assuminh it would be better, more silent).
Everything works perfectly, the lab supply is silent now!
I forgot to add A additional capacitor on the 12V fan supply but, I have not checked the ripple.... just thought of it while typing this post (maybe I open it up again but seems to work perfectly so I think I will leave it like this)

- Put the thermristor of the PWM fan controller into the hole next to the NTC on the board.
- Stored the original fan inside the supply, If I ever need it

[5U4GB]

instead of a custom temperature fan controller, I bought a PWM fan controller on Aliexpress:
Search for "12V PWM fan controller"

Hmm, for only a tiny bit more you can get something mainstream like the Arctic temperature-controlled fans, they use a FDB for quiet operation and come with a built-in temperature sensor on a short cable.  For an 80mm fan you want the Arctic F8 TC.  I used to have one of those somewhere but ditched a whole bunch of fans ("the fan club") during a clearout a year or two back, sigh.

[5U4GB]

I forgot to add A additional capacitor on the 12V fan supply but, I have not checked the ripple.... just thought of it while typing this post (maybe I open it up again but seems to work perfectly so I think I will leave it like this)

That would be interesting to see and was actually my first thought, have you partially negated one of the main benefits of a linear supply by adding switching noise to parts of the circuit?

[littleboot]

I forgot to add A additional capacitor on the 12V fan supply but, I have not checked the ripple.... just thought of it while typing this post (maybe I open it up again but seems to work perfectly so I think I will leave it like this)

That would be interesting to see and was actually my first thought, have you partially negated one of the main benefits of a linear supply by adding switching noise to parts of the circuit?

Hmm, for only a tiny bit more you can get something mainstream like the Arctic temperature-controlled fans, they use a FDB for quiet operation and come with a built-in temperature sensor on a short cable.  For an 80mm fan you want the Arctic F8 TC.  I used to have one of those somewhere but ditched a whole bunch of fans ("the fan club") during a clearout a year or two back, sigh.

Thank you for your reply I decided to open up the lab supply again.
I wish I knew about the Arctic F8 TC sooner I would have probably used it, however I'm quite happy with the AliExpress fan controller because I can configure it.
I'm glad I opened up the supply again and did a measurement, the supply noise is horrendous (did not expect it to be this bad ). When I'm finished with the measurements I will post measurement data before and after as well

[littleboot]

Finished the measurements, as mentioned before the supply voltage is horrible, not only that it is actually load dependent ~20Vrms (light load, new fan standby speed) not 12Vrms.
I don't like the over voltage for the fan, but if it dies it dies, problem for future me
The fan controller AliExpress page is says it will operate from 8V to 18V. I looked up the LDO part number (78l05) on LCSC and it seems it can handle 35V max, assuming the 0603 capacitors 0.33uf and 0.1uF are 35V, 50V or higher I should be fine.

I attached my full notes including measurement data as pdf.

I measured the supply voltage with my scope in the following situations:
- original fan;
- original fan +200 uF (two SMD solidstate 25V 100uF capacitors https://www.lcsc.com/product-detail/Solid-Capacitors_AISHI-Aihua-Group-SVZ1EM101E06E00RAXXX_C320569.html)
- fan controller without fan
- fan controller without fan +200 uF
- fan controller with fan (ID-COOLING NO-8010-PWM)
- fan controller with fan (ID-COOLING NO-8010-PWM) + 200uF

again another quick project that took way longer then expected