Easy lab PSU

[Nigel Goodwin]

I've mentioned previously about the Hiland LCD PSU kit from Banggood, well I've finally got it finished!

My last 'problem' was sourcing a suitable mains transformer for it, as they tended to be too large, or too expensive - eventually I opted for a 24V 4-6A SMPSU board from Banggood, at a fraction of the price of a transformer. I modified the PSU (by simply adding a resistor to the feedback network) to convert it to 30V DC out - the PSU kit calls for either 24V AC from a transformer, or a 30V DC supply. I saw no point in feeding the DC through the bridge rectifier, so I wired the 30V directly to the reservoir capacitor.

It's particularly nice to use, as you set the voltage and current via rotary encoders, and pressing the controls stores the settings to remember it next time you turn on.

Here are a couple of pictures:

 

[Ian Rogers]

It looks good.... Nice to know they think amperage comes from dried grapes...

 

[dr pepper]

I like the case are they available separately?

 

[Tony Stewart]

**broken link removed**

 

[Nigel Goodwin]

I like the case are they available separately?

Yes, it's only available separately - it's not a complete kit, just a collection of separate parts.

 

[alec_t]

Nice to know they think amperage comes from dried grapes...

They must have had a raisin for spelling it that way .

 

[Nigel Goodwin]

They must have had a raisin for spelling it that way .

Oops!

Hadn't noticed I'd done that.

 

[jasonmrc]

Hi

Can you share the front panel design ?

 

[Nigel Goodwin]

Hi

Can you share the front panel design ?

No problem:

 

[jasonmrc]

Hi Nigel

thanks for the image. I will design a laser-cut SVG file. so anyone can cut it...

 

[Tony Stewart]

I have noticed that inexpensive Chinese variable supplies have poor protection from non-linear (stripLED) overload. In my case 3 x 5 m stripleds with tiny LEDs. Both failed catastrophically in less than a week. Perhaps driven to or beyond the rated current limit.

 

[audioguru]

Banggood and a few other Chinese places copied the defective Greek Kit that I talked about and fixed 15 years ago at www.electronics-lab.com because it had many overloaded parts and failed soon. Here is another website that copied the problems I found with this kit:

 

[jasonmrc]

No problem:

View attachment 120605

After assembling the Hiland avr psu. I noticed that stability was poor. I fixed the issue by replacing the 22n to a 100nf capacitor on the transistor board and also wire an optocoupler on the base on the transistor which the avr drives the voltage.

Also across the 5v Zener, I added another 100nf to smooth any spikes entering the avr.

 

[Pommie]

Took me a while to spot the grape joke.

Looks like I'll be placing an order with banggood unless someone confirms Audios comment about it being flawed. The one with the LCD appears to be a more recent design with an AVR.

Mike.

 

[Nigel Goodwin]

Took me a while to spot the grape joke.

Looks like I'll be placing an order with banggood unless someone confirms Audios comment about it being flawed. The one with the LCD appears to be a more recent design with an AVR.

The AVR one mentioned in this thread is completely different.

 

[audioguru]

Nigel, in Google and at Banggood I could not find the Hiland Power Supply Kit that looks the same as yours.

 

[Nigel Goodwin]

Nigel, in Google and at Banggood I could not find the Hiland Power Supply Kit that looks the same as yours.

???

I just searched for 'Hiland Kit' on Banggood, and this was the first hit:

0-28V 0.01-2A Adjustable DC Regulated Power Supply Module DIY Kit Short Circuit Current Limiting Protection

Only US$20.99, buy best 0-28V 0.01-2A Adjustable DC Regulated Power Supply Module DIY Kit Short Circuit Current Limiting Protection sale online store at wholesale price.

www.banggood.com

 

[audioguru]

I see that Banggood sells clothing, shoes and many power supply kits.
Your kit has no detailed spec's and in Chinglish they say, "please be sure to carefully" so you better watch out!

 

[gophert]

They must have had a raisin for spelling it that way .

When I go camping, I just bring an extension cord and set up my tent next to a currant bush.

 

[Pommie]

Nigel, how did you modify the 24V supply to give 30V?

Mike.