Power Supply Kits? - Page 1
Forum section: electronics / testgear

author: tehjrow
author_rank: Contributor
timestamp: May 03, 2015, 02:59:52 pm
content: I want to build a bench power supply and can't really find any decent kits. The only one I really found was the Elenco kit and it seems a bit basic (no voltage gauge). Anyone know of any good kits with output gauges (analog or digital) or super good write ups on building one?

author: drakke
author_rank: Regular Contributor
timestamp: May 03, 2015, 04:59:39 pm
content: I've looked as well and did not find any good ones.I did find a lot of power supply modules on ebay. I also found digital voltage gauges. So I think one way is to find a good case and start assembling your own from compatible parts. You can buy 10-turn Bournes pots, banana jacks, transformers very easily as well.It probably won't be less money and probably will cost more than a commercial PS though.

author: dom0
author_rank: Super Contributor
timestamp: May 03, 2015, 05:27:35 pm
content: From a financial point of view it is only cheaper to build your own lab supply if you already got the expensive parts for free. Expensive parts are mostly the case, heat sinking, transformer, depending on range also power transistors and if you want any, then 10-turn pots (about 6 € ea. new in small quantities).

author: chibiace
author_rank: Regular Contributor
timestamp: May 03, 2015, 05:36:57 pm
content: a nice case is hard to do for most people.

author: Richard Crowley
author_rank: Super Contributor
timestamp: May 03, 2015, 05:41:06 pm
content: It is easy enough to add voltage (and even current) displays to any power supply with inexpensive Chinese modules available on Ebay.For example:http://www.ebay.com/itm/100V-100A-DC-Digital-Voltmeter-Ammeter-LED-Voltage-Current-Amp-Volt-Meter-Panel-/131330606906However, as @dom0 said, you will probably spend more money building it yourself than just buying a budget new unit (or a brand-name used one). The big parts like the transformer turn out to be rather specialty items neither readily available, nor at budget prices.Now, if your reason for DIY is to learn electronics, then maybe the extra expense is worth it. At least study the manuals and schematic diagrams for bench supplies to see what is available and the complexity of the circuit needed to support the various features. Note that Dave did a series of videos on designing and building a bench supply...http://www.eevblog.com/2011/11/28/eevblog-221-lab-power-supply-design-part-1/http://www.eevblog.com/2011/11/29/eevblog-222-lab-power-supply-design-part-2/http://www.eevblog.com/2011/12/03/eevblog-224-lab-power-supply-design-part-3/http://www.eevblog.com/2011/12/07/eevblog-225-lab-power-supply-design-part-4-pwm-control/

author: rdl
author_rank: Super Contributor
timestamp: May 03, 2015, 05:49:01 pm
content: Yeah, other than Elenco, pretty much everything else will just be a board and parts. I built one that way several years ago - pre-assembled LM350 board, $5 panel meter, switch, binding posts, RadioShack transformer all inside a cheap, thin aluminum, snap together Bud box. Total cost probably close to $50, but I already had everything but the box and board, so it made some sense at the time and it works fine for what it is. Of course, for a halfway decent off the shelf bench supply you're probably going to have to spend 3x that much.