Inexpensive bench top power supply - Page 1
Forum section: electronics / projects

author: shadewind
author_rank: Frequent Contributor
timestamp: May 02, 2011, 07:28:50 am
content: I've been thinking about getting a function generator and a bench power supply for while and after seeing Dave's latest blog I thought I'd go ahead and get one of each.I've already decided to get an Instek SFG-1013 (same as SFG-1003 but with voltage display) but have yet to decide on a PSU.I will be doing both digital and a little audio and will be needing about 3A of output. Dave recommended DIY but I have so many other projects that I hardly have time. Agilent has the U8001A which looks quite nice but is probably as high as I want to go. Any recommendations?

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: May 02, 2011, 07:38:38 am
content: Quote from: shadewind on May 02, 2011, 07:28:50 amNot an actual recommendation, more like an prediction , you will end up in time, with three of four adjustable PSU's .The one that you had select as first, looks nice go for it .

author: Mechatrommer
author_rank: Super Contributor
timestamp: May 02, 2011, 09:58:02 am
content: i did research on it, and eevblog is all you need, but the search engine can be crappy, my workaround is click home->search from there, dont search from certain thread, type "bench power supply" or "function generator" etc, you can see alot of things atten, agilent, bk precision etc. i wish i can google (eevblog) for you, but i believe by doing that yourself, you'll have more fun

author: DrGeoff
author_rank: Frequent Contributor
timestamp: May 02, 2011, 10:30:16 am
content: If you are doing any serious audio work then you may find you need one that goes up to at least 40V, preferably 48V for phantom power tests. If you are just messing with a few op amps then +/- 15V should be fine.Having said that, you may be better off DIY'ing the audio PSU for its appropriate functionality rather than use a regular bench PSU, since you'll also need at least one bench PSU as well.

author: shadewind
author_rank: Frequent Contributor
timestamp: May 02, 2011, 02:13:33 pm
content: Yeah, that's what I planned on just getting a general bench top power supply. But the question is... looking at Farnell, I can get one of them dual output Caltek (some Chinese brand I asume) supplies for quite a bit less money than the Agilent mentioned above. There's gotta be some disadvantage to choosing a cheaper power supply with more features? Would you recommend going with a more expensive name brand power supply or does it really matter?

author: shadewind
author_rank: Frequent Contributor
timestamp: May 02, 2011, 05:41:05 pm
content: This is the one I mean:http://se.farnell.com/caltek/psm2-5a/psu-laboratory/dp/1270465On the other hand, looking at this thread makes me a bit nervous about it:http://www.rcgroups.com/forums/showthread.php?t=1030827&mode=linearIs it really safe to use if quality control is so bad? I don't want to get shocked or killed...

author: DaveW
author_rank: Frequent Contributor
timestamp: May 03, 2011, 12:53:56 pm
content: I've used a few of these (and own a 30V, 10A at home for higher current work). The noise and performance is not as good as power supplies like the agilent/TTI etc. However, it is good enough for 99% of electronics projects, unless you are constructing audio amplifiers that are very sensative/intolerant of ripple. And if you are, a few capacitors across the rails will probably make it perform far better. The construction isn't that bad overall, and I've never seen one develop any fault that could be dangerous.If you are looking at that price range I would suggest avoiding Mastech power supplies, have seen lots of them DOA-although would be curious to hear other people's experiences with them.And after not too long you'll probably end up with lots of different power supplies around, having one power supply with dual rails or 10A on a single rail can be very useful at times

author: shadewind
author_rank: Frequent Contributor
timestamp: May 03, 2011, 01:47:35 pm
content: I was thinking of getting the 5A model first but Farnell doesn't have any in stock and won't be having for quite a while either (103 days!). Is it worth waiting for that or could I just as well snag one of the 2A models (2A per rail och 4A in parallel) and be done with it? Is it likely I will need 5A? Are there other places that stock these?Edit: Actually, they've ceased stocking them at all! They only have the 2A model now.Anyway... it says it can be connected in serial so I should be able to get up to 60V from it, right? As someone stated, +48V could really be very useful

author: DaveW
author_rank: Frequent Contributor
timestamp: May 03, 2011, 05:03:12 pm
content: You can get 60V from it, it has a proper serial mode. And although Farnell don't have them, CPC a division of Farnell does...http://cpc.farnell.com/caltek/psm2-5a/power-supply-laboratory/dp/IN04891http://cpc.farnell.com/caltek/psm3-5a/power-supply-bench-led-3ch-30v/dp/IN05511Bizarrely the 3 channel is cheaper than the 2 channel-always useful to have a 5V rail I guess!

author: shadewind
author_rank: Frequent Contributor
timestamp: May 03, 2011, 08:25:13 pm
content: CPC doesn't seem to want to deliver to outside of the UK (Sweden in my case) without a bit of hassle. So... what to do?

author: deephaven
author_rank: Frequent Contributor
timestamp: May 03, 2011, 09:01:27 pm
content: http://se.farnell.com/caltek/psm2-5a/psu-laboratory/dp/1270465?Ntt=PSM2/5A

author: shadewind
author_rank: Frequent Contributor
timestamp: May 03, 2011, 09:34:00 pm
content: Well, that's in stock in 104 days it says. That's more than three months. I don't really want to wait that long for something I might not use. Unless I actually will use it but I can't think of anything right now.

author: IanJ
author_rank: Unknown
timestamp: May 04, 2011, 09:21:01 pm
content: Hi,Here's my PSU...........does what it says on the tin.......cost me about 170 UKP.Model = CSI 3005XIII2 x 0-30vdc (5amp)1 x 5vdc (3amp)Parallel & Series functions (0-10A or 0-60V functionality)http://www.circuitspecialists.com/level.itml/icOid/8613There are plenty others in the range.....Ebay "bench power supplies"Pic below is 3-amp version of my 5-amp.