Benchtop Power Supply Question

[diif]

Re: Benchtop Power Supply Question

I use my 30v 3A power supply for the majority of my power supply use.
I have a device for injecting low voltage and high current for help with detecting shorts and I have a 900W boost converter for the occasions I need more than 30V.

[jiroy]

Re: Benchtop Power Supply Question

I'd say if you're just starting with learning electronics, 0-30V and up to 5-6 Amps should cover plenty of ground. If you plan on doing experiments with many "heavy duty" DC motors (i.e. anything size 540 and up), consider dropping the voltage requirement a little (down to 24V, perhaps) to get more current: 10-15A for such motors. Even then, that might not be too cheap, considering 10 Amps at 24V is already a 240 Watt PSU, and that can be expensive.

IMO, best way is to get several different PSUs, and not necessarily bench type. In fact, I *still* don't have a (working) bench PSU, despite experimenting with projects quite often. Majority of small breadboard projects I power with small plug-in power adapters (5V, 9V, 12V, 15V, etc.) And when I need more heavy current with low voltage, that's where my ATX PSUs come in. For higher voltage, I've used various contraptions - from non-isolated resistive mains droppers (light bulbs, soldering irons, countertop ovens, and etc.) to AC dimmer-controlled transformers.

It's certainly more cumbersome to do it my way, but it's also been cheaper (and I find it more rewarding, since I sometimes have to *actively* think about how I want to power something, rather than just dial in a number on a bench PSU and hope it all works fine.)

That said, there have been times where I did wish I bought or made an adjustable PSU. Most of these were when I needed low voltages (3.3V or less) at medium to high currents (more than 2-3 Amps) and good regulation. But again, I think 0-24V or 0-30V @ up to 3-5 Amps should work well enough for you to get into electronics. That along with a computer ATX PSU and a 60-90 Watt 19-20V laptop adapter should cover a good deal of projects.

Right to the point !! ... I have all kinds and for all purposes . Lately , I had to repair a car stereo at home . I needed something 12v with powerful amperage . 10 minutes of thinking and opening whole boxes and then I grabbed an old computer PSU which did the job fairly well . When I finished the repair and On testing CD's , i had to limit the sound volume to not more than 50% , or else , the PSU would cut off .
Yet , In a room , I have like 5 or six laptops on a one huge table , and I've got sick of adapters and cables , inlets and outlets , so I decided to build one powerful unit to replace all the adapters . I'm now checking my old electronic schematics to choose the convenient one .

[momaka]

Re: Benchtop Power Supply Question

I'd say if you're just starting with learning electronics, 0-30V and up to 5-6 Amps should cover plenty of ground. If you plan on doing experiments with many "heavy duty" DC motors (i.e. anything size 540 and up), consider dropping the voltage requirement a little (down to 24V, perhaps) to get more current: 10-15A for such motors. Even then, that might not be too cheap, considering 10 Amps at 24V is already a 240 Watt PSU, and that can be expensive.

IMO, best way is to get several different PSUs, and not necessarily bench type. In fact, I *still* don't have a (working) bench PSU, despite experimenting with projects quite often. Majority of small breadboard projects I power with small plug-in power adapters (5V, 9V, 12V, 15V, etc.) And when I need more heavy current with low voltage, that's where my ATX PSUs come in. For higher voltage, I've used various contraptions - from non-isolated resistive mains droppers (light bulbs, soldering irons, countertop ovens, and etc.) to AC dimmer-controlled transformers.

It's certainly more cumbersome to do it my way, but it's also been cheaper (and I find it more rewarding, since I sometimes have to *actively* think about how I want to power something, rather than just dial in a number on a bench PSU and hope it all works fine.)

That said, there have been times where I did wish I bought or made an adjustable PSU. Most of these were when I needed low voltages (3.3V or less) at medium to high currents (more than 2-3 Amps) and good regulation. But again, I think 0-24V or 0-30V @ up to 3-5 Amps should work well enough for you to get into electronics. That along with a computer ATX PSU and a 60-90 Watt 19-20V laptop adapter should cover a good deal of projects.

[JC173]

Re: Benchtop Power Supply Question

Again back to what you are going to do with it... and one size won't fit all.

The problem is, I don't know enough about the hobby yet to know exactly what I need or what I might end up using it for.

Maybe it's worth mentioning about basic security, when talking about power supplies?
What current protection devices do you use in your workshops?

https://www.youtube.com/watch?v=wRFRwOnLsZI&t=1s
Great simple thing.

I'm working on building one right now actually

[UNITRAX]

Re: Benchtop Power Supply Question

Maybe it's worth mentioning about basic security, when talking about power supplies?
What current protection devices do you use in your workshops?

https://www.youtube.com/watch?v=wRFRwOnLsZI&t=1s
Great simple thing.

[eccerr0r]

Re: Benchtop Power Supply Question

A TV that uses 120V to power LED strips at 3A would mean it's a very big TV since it means it's drawing 360W, that's very very bright, my 40" LED TV is less than 60W...

And it's a switching PSU, it's wattage limited - more volts means less amps.

I wouldn't trust a 120V switching PSU for low voltages...so if you really need low voltages more than high voltages, I'd stay away from it especially if you need more current.

Again back to what you are going to do with it... and one size won't fit all.

[stj]

Re: Benchtop Power Supply Question

look for info in the tv section

[JC173]

Re: Benchtop Power Supply Question

no,
the leds often have multiple chips in them and the strips use around 80v

Reeeally... how do I know if there are multiple chips?

Would the 120V supply be adequate given that it only supplies 3A?

[stj]

Re: Benchtop Power Supply Question

no,
the leds often have multiple chips in them and the strips use around 80v

[JC173]

Re: Benchtop Power Supply Question

led strips from tv's = pretty high voltage

Somewhere between 27 and 29 volt given the ones I have now. It's roughly 3.3v per LED right?

[stj]

Re: Benchtop Power Supply Question

led strips from tv's = pretty high voltage

[JC173]

Re: Benchtop Power Supply Question

That's a fair point

Point is I'm not really sure what I need. I intend to do mainly smaller projects, but I want to test salvaged circuits or LED strips at the moment.

[stj]

Re: Benchtop Power Supply Question

cant answer the question unless we know what you want it for.
maybe you only need 30v - maybe you need upto 200
maybe you only need 3A - maybe you need 60A

it all depends on your use of it.

[JC173]

Hey all,

Relatively new to the hobby, and I'm looking to purchase a benchtop power supply unit.

I'm looking at this range of units, but I don't understand what voltage and amp range I should shoot for. Also, why would the 120v unit only produce 3 amps?

https://amzn.to/3ZiQqvd