Bench Power Supply

[GodIsRealUnless DefinedInt]

I just use data center power supplies, USA engineered and Chinese manufactured.

Then I get one of a million bucking converter power supply units on Amazon or AliExpress.

Unless you want a Chinese engineered and Chinese manufactured switching power supply in your bench top supply you could always do similar. IIRC it was $20 for my data center power supply on eBay.

Just another option.

I miss my linear supply I built many moons ago in uni, I will be building a new one soon.

[ledtester]

Well, after reading all of your comments, I requested it. It should be here today. I got the 30V 10A model.

Is there anything any of you would want  me to test on the unit, as long as I can do it with a DMM. I don't have a scope. Or, is there anything you want met o specifically look at or try?

For educational purposes you can make the measurements I described in this post:

https://www.eevblog.com/forum/beginners/bizarre-behavior-from-24v-dc-power-brick/msg3568432/#msg3568432

Some people have gotten a tingling sensation from ungrounded switching power supplies when they've touched exposed metal. As an experimenter the presence of this AC voltage is good to know about.

[DW1961]

The images or posted here:

https://www.eevblog.com/forum/testgear/kungber-bench-ps-tear-down-images-as-requested/

[exe]

When you take it apart, check the mains input and power switch to see if the neutral is switched and/or fused instead of the line.

Shouldn't the switch be on both wires because live and neutral are sorta interchangeable? I mean, I can put a EU plug in two different ways, swapping live and neutral. Or am I confusing something? May be it's a EU problem

[Zero999]

When you take it apart, check the mains input and power switch to see if the neutral is switched and/or fused instead of the line.

Shouldn't the switch be on both wires because live and neutral are sorta interchangeable? I mean, I can put a EU plug in two different ways, swapping live and neutral. Or am I confusing something? May be it's a EU problem

The subject has been discussed at length before. If it's just a power switch and isn't intended to protect against electric shock, then it doesn't matter whether it's in the live, or neutral, but as a general rule, in areas with polarised plugs, it's normally put on the live side.

[beanflying]

When you take it apart, check the mains input and power switch to see if the neutral is switched and/or fused instead of the line.

Shouldn't the switch be on both wires because live and neutral are sorta interchangeable? I mean, I can put a EU plug in two different ways, swapping live and neutral. Or am I confusing something? May be it's a EU problem

In the case of this Power supply if you follow the link to the new thread the OP opened it is an IEC plug so 'in theory' it is polarised and earthed but the polarity of course relies on the Elecrician or anyone 'playing' with being one wired the outlets correctly.

The simple rule is if it is plugged in and switched on at the wall ASSUME it is live to Earth.

[Old Printer]

It seemed to start with the lower tier Chinese manufacturers and since they frequently just copy from each other it has become common. For most people it's probably a non-issue.

Rigol doesn't do it on their DP800 series. Siglent doesn't appear to do it either. And of course HP, Agilent, Tektronix generally don't (or maybe never) do it



As for this particular unit, I'd go for it. Can't beat the price and power supplies are something you always need multiples of.

The Tek CP250 is a great hobby level supply. A few years back one of the big tech schools went bust and dumped pallets of them on the surplus market under the BK Precision badge. I managed to get a few for $20 ea on evilbay. They go for some serious money under the Tek badge. Best part of that is that Tek produced a great service manual for it with their usual detailed troubleshooting guide and clear schematics and parts list. The manual can be had on ebay for $10 on CD. If you are looking for affordable power supply's don't overlook the used market. Many of the older units were built very well, have service manuals available online and you can learn a bunch by fixing up an old one.