Korad KKG305D/KKG305P - Page 1
Forum section: electronics / testgear

author: xKertx
author_rank: Regular Contributor
timestamp: March 09, 2024, 02:44:45 pm
content: Hello,I think this power supply deserves its own thread because it's a little different than other Korad PSUs.I made a small review of it:https://youtu.be/-Rq0KUz-qd0?si=IHR3fmuLgAl-uS8OThis is my first review ever.Also, sorry for my bad english. I'm from Finland and I don't speak English very often.Anyway, I think the main differences with other Korad models are:Much better display.Solid state relays, so no relay noise.Better cooling.Amp meter can go down to milliamps.Unfortunately, the memory overwrite bug is still there.

author: ataradov
author_rank: Super Contributor
timestamp: March 09, 2024, 04:48:02 pm
content: Is this a Noctua fan out of the box? Or is this a mod?

author: xKertx
author_rank: Regular Contributor
timestamp: March 09, 2024, 04:53:53 pm
content: Quote from: ataradov on March 09, 2024, 04:48:02 pmI have replaced the fan with the Noctua NF-A8 (80x80x25mm).The original fan made somekind of ticking noise. Now its almost silent. And i think the Noctua fan pushes little more air.

author: ataradov
author_rank: Super Contributor
timestamp: March 09, 2024, 05:05:15 pm
content: It might be useful for the thread to know the exact model you used, so people won't have to guess what fits. Although all those fans are pretty much the same in size.

author: xKertx
author_rank: Regular Contributor
timestamp: March 09, 2024, 05:12:05 pm
content: Quote from: ataradov on March 09, 2024, 05:05:15 pmI have edited my previous post.It's Noctua NF-A8.But any 80mm fan will fit.

author: 5U4GB
author_rank: Super Contributor
timestamp: March 10, 2024, 10:15:11 am
content: Quote from: xKertx on March 09, 2024, 05:12:05 pmThat's a PWM fan, does that mean it's got proper control or does it always run like the 3005D/P? I was trying to see the connector in the video but it was a bit hard to see.Thanks again for the video, it looks like a significant improvement over the 3005D/P series.

author: xKertx
author_rank: Regular Contributor
timestamp: March 10, 2024, 10:27:07 am
content: Quote from: 5U4GB on March 10, 2024, 10:15:11 amYes, it's a pwm fan, but if you leave the rpm and pwm wires unconnected and connect only + and -, then it will act like a normal fan.I didn't have the right connector so i had to cut the wires and used the connector from the old fan.It is always on, but it is on low speed by default. The fan is temperature controlled by the power supply so it will speed up when needed.

author: ass20
author_rank: Regular Contributor
timestamp: March 10, 2024, 12:15:58 pm
content: hiCan you make photo of used ic ? what is cpu used on this korad?

author: glitchcatcher
author_rank: Contributor
timestamp: March 11, 2024, 05:31:16 pm
content: Finally a thread about the KKGs! A bit of a weird product, hardly available and still not listed on the Korad website!I have a Warsaw connection, so it was easy for me to get a KKG3010P last year at NDN. It was my choice of Korads because it fits the Korad KEL102/3 load perfectly with that green displayQuote from: xKertx on March 09, 2024, 02:44:45 pmOn the German forums someone wrote about these KKGs and its improvements:"The memories are no longer overwritten when you change the settings, but only at the touch of a button"That is unfortunately also not true for my model.Attached some pictures for comparison.When I opened the case, I slid the cover backwards which was a mistake (and also unnecessary, all you need to do is grab the bottom at the sides and pull outwards, then lift up carefully).The screw holding the case handle scratched the PCB! Too little clearance, and the PCB is also bending upwards a bit. A design flaw!

author: ataradov
author_rank: Super Contributor
timestamp: March 11, 2024, 05:41:17 pm
content: Interesting that there is a handle. The pictures in the OP do not show it. And I mod my KA3005s with a regular furniture drawer handle, which makes them way easier to move.

author: bingo600
author_rank: Super Contributor
timestamp: March 11, 2024, 05:46:20 pm
content: They're here - Not many other hitshttps://ndn.com.pl/en/szukaj?controller=search&orderby=position&orderway=desc&search_query=kkg&submit_search=

author: 5U4GB
author_rank: Super Contributor
timestamp: March 12, 2024, 12:55:48 am
content: Thanks for the additional photos, it looks like they've now got metal-to-metal contact on the struts and top case to try and earth the top part of the case rather than thesomewhat dodgy mechanism described here:Quote

author: xKertx
author_rank: Regular Contributor
timestamp: April 12, 2024, 07:29:37 am
content: Quote from: ass20 on March 10, 2024, 12:15:58 pmI finally had time to open it up again and swap the capacitors to Panasonic and Vishay long life caps.I guess this is the chip you are talking about?I think it has a "KORAD01" written on it and some other numbers. Really hard to tell because of the shiny laquere coating.

author: feri666
author_rank: Newbie
timestamp: August 10, 2025, 09:35:44 am
content: I have a Korad KKG305P power supply.When I set the voltage between 7V and 15V, the voltage fluctuates between 7V and the set value. For example, if I set it to 12V, the voltage fluctuates between 7V and 12V, up and down, even without a load.If I set the voltage lower than 7V or higher than 16V, it works normally.What could be the problem? Which component could be faulty?

author: 5U4GB
author_rank: Super Contributor
timestamp: August 11, 2025, 02:46:07 am
content: Sounds more like it could be a configuration error, do you have it in CC mode, or some sort of other limiting applied where it'd drop the voltage to compensate?

author: krzys-iek
author_rank: Newbie
timestamp: August 13, 2025, 06:44:08 pm
content: HelloI have just bought this one. Important question! This model is loud - buzzing noise coming from transformer winds. Always, w/o and with load. Typical low pitch buzz from the mains 50/60Hz. WHY? It then travels (this sound, so small vibrations) onto my desk etc. Very annoying! Old model did not have that, it was silent.Is it same with your model guys? I wished for upgrade but keeping that on for hours will drive me crazy!

author: xKertx
author_rank: Regular Contributor
timestamp: August 13, 2025, 06:55:44 pm
content: Sounds like a faulty unit. I would return it.Mine is dead silent (after i replaced the fan) and no vibration.

author: krzys-iek
author_rank: Newbie
timestamp: August 13, 2025, 07:56:55 pm
content: Thanks, will do so. Crap...Mod time, did you replace green led for OUT? I wish they gave different color for that one. Easy to miss that output is ON when ALL the info is green lit! Is not it? I wish it had different LED colors for ON/ CV /CC dont you think?I dont know if you have took it apart (hehe Dave) deep enought to spot if these are SMD LED or THT 3mm ones? And if V accross this LED is okay to just resolder other popular color.

author: xKertx
author_rank: Regular Contributor
timestamp: August 14, 2025, 03:38:26 pm
content: Yeah, it would be nice if the backlight of the "out" text could be replaced to red one.But i have not disassembled it that far.When examing it with a flashlight, it seems that the whole display is a one single panel.So i guess it would be real PITA to disassembly it. First you need to desolder it and then somehow cut out the backlight led of this digit. Then glue a new one in and solder the whole thing back to pcb.I've been thinking if it would be possible to just connect another red LED in parallel with the existing "out" text. A red led somewhere on the screen would be better than nothing i guess.

author: krzys-iek
author_rank: Newbie
timestamp: August 16, 2025, 12:36:24 pm
content: Thanks, ahhhh Korad! Other solution is RED backlight of the on/off switch itself. Seen that on cheep UNI-T models. Now we have "matrix" green all other the place so as ppl say - easy to miss that output is ON!CV, CC also should not be green! Old version clearly manifested that we are in CC mode or output is ON.Overall this model they say is a step forward and better. But small things should be thought before they release. Even asking here and then drawing conclusions. Red backlight is not more expensive to make for sure so why not to do that?Handle to carry would be nice bonus too, with a possibility to unscrew it if you do not needed it.PSRubber of on/off switch I guess is not transucent even for strong LED? You know just to shine thru. That would be probably easy to do w/o any need to drill etc. I have sent my buzzzzzzy model back to shop and will be getting a replacement.

author: krzys-iek
author_rank: Newbie
timestamp: August 19, 2025, 02:47:50 pm
content: I got a new one, this one produces even more annoying buzzwhat the f...