FEDEVEL
Platform forum

𝔎𝔦𝔯𝔞 , 06-27-2026, 05:17 PM

I have bought a 24V 100W DC power supply which I originall intended for a LED strip but I got the wrong voltage since the LEDs are 12V. I do not know what to do with this spare 24V now so I asked ChatGPT and it suggested me to DIY a bench power supply which sounds like a cool project. I have watched some vids like this one
https://www.youtube.com/watch?v=wI-KYRdmx-E

So, based on my research are the following parts fine?
24V PSU ✅ already have it
buck boost converter like the ZK 4KX or ZK 5KX I don't know their differences but they are priced so closely, check them out
https://www.aliexpress.com/item/1005004308238770.html?pdp_ext_f=%7B%22order%22%3A%221678%22%2C%22spu_best_type%22%3A%22price%22%2C%22eval%22%3A%221%22%2C%22fromPage%22%3A%22search%22%7D&utparam-url=scene%3Asearch%7Cquery_from%3A%7Cx_object_id%3A1005004308238770%7C_p_origin_prod%3A
banana plugs for the output terminals
AC socket with a flip switch and fuse holder
some 12AWG wires
a AC plug which I would have to cut and tighten its L,N and GND wires to the PSU
3D printed case I have to design

Am I missing anything crucial for a power supply?
What are your thoughts on this project overall

, 06-27-2026, 05:23 PM

🤖 In the meantime, here’s a response from the [FEDEVEL AI HW Assistant]().
It helps to find relevant resources for your question, but it may make mistakes as it’s still in early development.

This is the response from the AI Assistant:
Your plan is a solid foundation for a DIY bench power supply. Let's break this down using insights from power supply design principles shown in our tutorials:

**Key Components You're Missing:**
1. **Output Filtering/Decoupling**
Add 100-470μF electrolytic capacitors at both input and output of your buck-boost converter for stability. In our USB-C design, we used careful capacitor placement near regulators ([Example](https://www.youtube.com/watch?v=W0bmmF1wTEs&t=2367)).

2. **Current Limiting/Protection**
Consider adding a resettable fuse (PPTC) on the output side. Our tutorial shows how protection diodes are critical for USB interfaces ([Protection Example](https://www.youtube.com/watch?v=W0bmmF1wTEs&t=893)).

3. **Voltage/Current Meter**
Add a digital panel meter (0-30V/10A units cost ~$5). Crucial for monitoring - we used LED indicators for different voltages in our design ([Voltage Indication Example](https://www.youtube.com/watch?v=W0bmmF1wTEs&t=8849)).

**Buck-Boost Converter Considerations:**
- The ZK-4KX (5A) vs ZK-5KX (8A) difference is current capability
- Ensure your 24V PSU can handle max input current:
For 100W output: 100W/24V = ~4.2A (leaves good headroom)
- Add heatsinking - these modules get hot at full load

**Wire Sizing Note:**
12AWG is overkill (handles ~20A). 14-16AWG would suffice for 5-8A loads, but better safe than sorry.

**Critical Safety Additions:**
1. Strain relief for all wire connections
2. Fuse on DC output side (fast-blow 8-10A)
3. Insulating barriers between AC and DC sections
4.

, 06-27-2026, 05:23 PM

Ventilation slots in 3D printed case

**Project Viability Assessment:**
This is an excellent intermediate project. From our tutorial experience ([PCB Layout Example](https://www.youtube.com/watch?v=W0bmmF1wTEs&t=5063)), you'll learn:

- Proper high-current routing techniques
- Thermal management
- Safety isolation distances
- EMI reduction through layout

**Cost Optimization Tip:**
Reuse components from old electronics - fuse holders, switches, and heatsinks often can be salvaged.

Would you like me to elaborate on any specific aspect like proper grounding techniques or thermal design considerations?

You can continue chatting with the AI Assistant here:
https://fedevel.com/hw-assistant

QDrives , 06-28-2026, 02:43 PM

Aliexpress... you build it, you test and let us know.

Robert Feranec , 06-30-2026, 05:14 AM

Just try it, have fun. Power supply is always useful

𝔎𝔦𝔯𝔞 , 07-03-2026, 04:14 PM

I had purchased the SK120 buck boost converter along with heat shrink tubes and the other stuff i mentioned

𝔎𝔦𝔯𝔞 , 07-03-2026, 04:15 PM

now i don't know if i want to add in a SPST rocker switch or not since im gonna be plugging this to AC socket which is going to have on off anyway

𝔎𝔦𝔯𝔞 , 07-03-2026, 04:16 PM

if so where would i put that spst switch? cant be between live and neutral before the dc power supply i dont think it can withstand plus if insulation isnt perfect i risk being electrocuted

QDrives , 07-04-2026, 02:43 PM

You still want the on/off switch on the device itself.
Best place for that is the AC line.

𝔎𝔦𝔯𝔞 , 07-28-2026, 12:12 PM

update, it works

𝔎𝔦𝔯𝔞 , 07-28-2026, 12:12 PM

I purchased crimps and ferrules to do this

𝔎𝔦𝔯𝔞 , 07-28-2026, 12:13 PM

18 awg wire sucked for crimping so i got 14 awg ones but they were too thick for me to insert the insulation through for the faston crimp connectors

𝔎𝔦𝔯𝔞 , 07-28-2026, 12:13 PM

will probably heatshrink those gold contacts, they are 240v exposed