Sell old nice cabinet p.supply and start from scratch. Or dismantle for parts? - Page 1
Forum section: electronics / general

author: Jan E L
author_rank: Contributor
timestamp: January 07, 2015, 11:15:01 pm
content: I want to build a power supply from scratch for the fun of it. And because I need one. For some weeks I have searched for one I dream about (2USB out, 0-30V 5A+, 5V, 12V) the price for those is out of question. So making one is kind of the only solution.Today my workplace wanted to dump an old Oltronix B32-20R with a really nice blue anodized cabinet because it blows fusesThe fault was easy to fix. So now I wonder what to do with it.Specs:600W / 0-32V / 20A / ext line sense / line regulation 1mV / 100% load regulation 7mV / 0.5 RMS mV /22kg (48lbs).It’s an old beast of a power supply(Produced 78-95)What price can be expected if I try to sell it?How long can you expect the caps to be functional? What about the expectation on transformer life? Don't want to ship it and get a angry phone because it died after a short time.Do I sell it to finance a nice ring transformer? Or gut it and use the cabinet for the project

author: KJDS
author_rank: Super Contributor
timestamp: January 07, 2015, 11:31:42 pm
content: They were very well designed and built units. I've got a 30A version for sale at £200 ish but it's been on for a while. I did sell one of the digital metered versions a while ago for somewhat more.

author: TerraHertz
author_rank: Super Contributor
timestamp: January 08, 2015, 08:35:50 am
content: Quote from: Jan E L on January 07, 2015, 11:15:01 pmSo now you have a FREE, working supply that does the 0-30V. And a nice one at that.Nothing there stopping you from building another supply, since having more than one is always good.QuoteNeither. Just keep it as it is. Unexciting, but practical.QuoteNot a lot. Not enough to buy a whole power supply's worth of new parts. And selling a nice working power supply to buy parts to make another power supply is... not likely to bring satisfaction.QuoteDepends on their usage history and original quality. Some last forever.QuoteSimplify! Just don't sell it.For a +5V and +12V supply, you realize virtually any piece of discarded office electronics will provide that? Old photocopiers, printers, LCD displays, etc, often have a such a supply as a separate module, sometimes switchmode, sometimes linear, that can be built into a simple box by itself. And the front panels of discarded PCs will often give a nice detachable panel with a couple of USB ports that can be built into your power supply box (with suitable current limiting) for your USB power out.After you have some working, reliable power supplies, then it's a lot easier to start a project to design one from scratch.

author: GreyWoolfe
author_rank: Unknown
timestamp: January 08, 2015, 03:18:18 pm
content: +1 on keeping and using it. Build another one. It is never a good idea to gut a working device to build another like device in the case. I also agree with the statement of lack of satisfaction in selling a power supply to buy a power supply. If you really want to do something with it, upgrade the caps.

author: IanB
author_rank: Super Contributor
timestamp: January 08, 2015, 03:34:11 pm
content: Quote from: Jan E L on January 07, 2015, 11:15:01 pmNeither. You have a nice working power supply that I would love to have on my bench. Keep it and use it.

author: Excavatoree
author_rank: Frequent Contributor
timestamp: January 08, 2015, 04:57:36 pm
content: I'd have to agree that's a great power supply with a usefull voltage range and good current capacity. I can understand wanting to build one's own supply from scratch, but it would be better to keep that one to use (will come in handy during the design process) even if that means saving up a bit longer for components to build your supply. Then, you'll have two, which is also very useful. Better two than one, as they say.

author: Phaedrus
author_rank: Frequent Contributor
timestamp: January 08, 2015, 11:38:35 pm
content: Keep it and convert an ATX unit for your +12V/+5V needs. But if you're in the US and decide to sell it, I might consider buying it if the price is reasonable.

author: Jan E L
author_rank: Contributor
timestamp: January 09, 2015, 09:02:44 am
content: Suspect it will end up as a benchwarmer. And I don't have room for one extra.Have a small 1 channel 0-18v 3A homemade power supply to use for construction of a new oneI already converted couple of ATX supply’s to get 5V/12V. And I guess I use same principle as a supply in to the new one for that part. But my experience from ATX conversions is that the 5v is stable. But the 12v is more like all over the place. Regardless of the load.All of the ATX supplies make my Hyperion Lipo charger (input 11-28v) sometime stop charging because the V falls to low. And that before it reach peak amp for the supplyOne can’t even turn it on.I have a scope on order. Guess I wait for it to arrive to have a look at the noise and overshoot on the Oltronix before I decide what to do with itThx for the tips.Also have an old rack mounted power supply cabinet that firstly was the project target. But it requires some sheet work to make it a good cabinet. Maybe I have to reconsider.