Opinions  about Thandar Ts3022s psu - Page 1
Forum section: electronics / general

author: mnm972
author_rank: Newbie
timestamp: October 31, 2012, 09:01:30 am
content: Hello,Can you please write your opinion on this psu for electronics hobbyDual outputhttp://www.used-line.com/tm_guide/model.cfm?model_id=415F00545E2B&old=1Thanks

author: mnm972
author_rank: Newbie
timestamp: November 01, 2012, 11:12:34 am
content: Hi Dave,Could you please share your insights on this PSU.I want to buy it second hand, will it do?Thanks!Quote from: mnm972 on October 31, 2012, 09:01:30 am

author: LaurenceW
author_rank: Frequent Contributor
timestamp: November 01, 2012, 08:11:42 pm
content: You can't really expect Dave to do specific reviews such as this - there is just too much kit out there, and he is just one guy. But there are LOADS of EEVBlog Forum users! And we can do LOADS of stuff...OK, first off, you ask, "Will it do?" In return, I ask you, "will it dowhat?" Make a good paper weight? Yes, it weighs a bloody ton. Can it make the tea? No, it is appalling in all butler-related duties. Is it a good power supply (for YOU)? Yes, or no, depending on what you want to supply power to.I have a close cousin of this power supply - a TTI PL330TP. It is the bloody dogs bollocks and would blow any cheapy sh!t from China CLEAN out of the water on ALL fronts. The spec sheet you quote really says it all. Compare these specs. HINT: most other power supply manufacturers won't even declare 25% of the number of specs you see here. Ask yourself: why not?This machine is:LINEAR not digital. So it weighs a ton, (good paper weight!), and produces good low noise outputVery high resolution V and A readings. You are getting one, EVEN TWO extra (believable) digits of display resolution (compared to cheaper supplies) out of the on-board meters, here. You'll never need to check the current or voltage with your DMM, if you need really need to verify fine results. This is a major thing (for my applications)Remote sensing, so the output can be ROCK solid, even for remote loadsProper low voltage on-off switched, so no nasty mains-on spikes.Built like a tank, only with more metal in it.Massively over-rated output stages. You simply wont blow this puppy up (unless you do something REALLY stupid involving plugging mains back INTO the output!)Look, just buy it. Or any other Thandar/TTI power supply (that meets your required power output requirements). It will outlive you, and any cheap $99 supply from who-knows-where (youKNOWwhere!)BUT have you thought about whether 2 x 30V at 2 A (can also be configured as 30V at 4 A or 60V at 2A) is enough/too much? If you just want 3.3V at 0.5A, it may be the latter...I don't see this particular model too widely available. If you have been offered this specific one, fine. If you are looking for something similar, there are plenty of others in the same TTI range (with varying specs- check before you buy).

author: Soertier
author_rank: Contributor
timestamp: November 02, 2012, 01:37:55 pm
content: Quote from: LaurenceW on November 01, 2012, 08:11:42 pmI am not sure if TTi is really superior in every aspect. I am also looking into buying a TTi power supply and from what I see there are some aspects that are not that great, some capacitors, broken mounts, etc, at least what I have seen on the forum.Would be nice if more users post some teardowns.

author: M. András
author_rank: Super Contributor
timestamp: November 02, 2012, 07:23:41 pm
content: you can always get faulty parts from suppliers, if you get a faulty you complain then get a new one or your current one fixed. nothing 100% fault safe. most of the reviews or teardows come from the user's own stuffs so dont expect to keep 600+usd worth power supplies at home from everyone

author: Soertier
author_rank: Contributor
timestamp: November 02, 2012, 08:08:09 pm
content: Quote from: M. András on November 02, 2012, 07:23:41 pmYou refer to my post?

author: M. András
author_rank: Super Contributor
timestamp: November 02, 2012, 08:12:46 pm
content: yes

author: Soertier
author_rank: Contributor
timestamp: November 02, 2012, 08:23:18 pm
content: Quote from: M. András on November 02, 2012, 08:12:46 pmI am talking also about the not so good choice of capacitors made by TTi in some models, this is nothing they can "fix", unless they change the design.There are many that have $600+ power supplies. I am not expecting teardowns from all of them, I just was just saying that it would be nice for some more users to post tearsdowns of power supplies.

author: circlethecat
author_rank: Newbie
timestamp: November 02, 2012, 10:00:02 pm
content: I agree with everything LawrenceW said.TTi supplies just work. All day. Every day.The only other PSU I'd consider is a big name vendor like Agilent or Tektronix but TTi has them beat on value.They sell well on ebay - if you need to upgrade you can easily get your money back.

author: LaurenceW
author_rank: Frequent Contributor
timestamp: November 02, 2012, 10:09:50 pm
content: Soertier, I don't think I am claiming that my TTI power supply is "Really superior in every respect". It is not superior in its purchase price, for example. Or weight. Although I will grant you that it is superior in every respect that matters to me.I am afraid that there is a lot of misplaced opinion (in my opinion) around the facts of capacitor reliability, and many stories hark back to the debacle about ten years ago of large bad batches of caps where the electrolyte chemistry was just wrong. This caught many good equipment manufactures such as Dell out. We have moved on since then. Yes, there are good manufacturers, and indifferent ones. Let us not forget that every cap manufacturer also has higher spec and lower spec components in their ranges, and then every equipment manufacturer who has a budget to work to, and maybe makes good or poor design choices as a result. The manufacturers making the poor design decisions end up in Dave's Dumpster.Most (but not all) capacitor failures that we are reading about here are when the caps are under the stress of SMPS switching circuits. Caps in linear supplies generally have an easier life. And even in the highly unlikely event that they ever gave out, anyone with enough knowledge to own a power supply in the first place should know enough to fix them.There are reputable companies such as Agilent, Fluke, etc. (you know the ones) who work very hard to build and then maintain their standing. Why would any manufacture risk that with cheap components? The returns/repair bill alone would rapidly outstrip the costs of the correct (not necessarily the best) choice of component in the first place.Look at what TTI Thandar did when the "broken clips issue" came up. How was that for good service? Yes, they cocked up with a poorly made mechanical part, which only showed up following the effects of probably rough shipping. But they reacted, and put it right. Do you think you would get the same attention from a far-eastern no-name supplier who does not have a reputation to maintain, and has achieved his end goal when his product shipped to you? I rather doubt it.Sorry if I am sounding a bit like a Thurlby Thandar evangelist! I'm not - and I have no connection with the company. But don't let one issue with a broken component (that was fixed), or misgivings about their choice of capacitors colour your judgement. I don't believe that they made a "not so good choice" of capacitors in these power supplies.At the end of the day, you do generally get what you pay for, especially if you take the long view. If you don't need it, or want to pay for reputation/support/performance, then through the wonders of eBay and cheap international shipping, then you don't have to. Cheap options do have their place, and it all goes back to the original question "It depends what you want it for."Teardown? Well, I can't be bothered with lots of pics and words, but here's what's inside my PL330TP that marks it out;Passive cooling design. Massive heat sinks, no fansMultiple output devices. SIX (I think) 2N3055s share the brief to produce up to 3A. Some cheaper designs might risk one or two devices onlyModular assemblies on good quality glass fibre boards, all components markedNeat wiring looms between boards. No cables flapping aboutAll through hole construction (but my PL330TP is no longer a current product)Documentation! Ask TTI nicely and they may even make available calibration manuals with with full circuit diagrams and detailed descriptionsOne FAT transformer for EACH power supply. Some manufacturers would get by with just one across multiple outputsOutputs are reverse bias protected (and the 5V output even has a built in over-voltage crowbar safety device)Good quality V and I pots, with sensible ranges and sensitivities.Did I mention this thing is bloody heavy?Individual output on/off switches, as well as mains on/off. When an output is off, you can set the max/constant current limitVery good transient load response. Difficult to catch the output out in you suddenly load or unload it.Good resolution and accuracy meters down to 10mV and 1mA. That is quite rare, and well worth having (in my view). Many supplies (including others in TTI's own range) stop at 0.1V and 10mA resolutionFast responding meters. My displays are screaming-clear half-inch red LEDs. I prefer these to LCDs but that's my own preference.Analogue preset pots allow internal recalibration if required (which it does not, in my case - mine is spot on)Good quality, dual (now, that's really useful) 4mm sockets and bare-wire screw terminal output connectionsOutput noise is below my ability to measure accurately, at probably less than 1mV rmsOutput AC mains ripple is below my ability to measure (lost in the noise)All-metal case construction. Later modules starting to use quite nice-looking plastic moulded componentsMine has a captive mains lead, not an IEC connector, which maybe newer products have. But then it's hardly portable, so once installed, the captive mains lead is no real issue.Maybestarting to look a bit dated, but then it is a power supply and not a fashion statement. New ones are maybe a bit cuter.A solid, very well behaved, box.A good number crop up on eBay, but you might have to pick your moment if you want a bargain. These are not cheap, and there's a reason for that. Still, cheaper than an Agilent/HP equiv, and there's a reason for that, too!

author: nack
author_rank: Regular Contributor
timestamp: November 02, 2012, 10:35:14 pm
content: Well actually I have also bought a PL330 from ebay (still unused in box) as well as another PL154 later on as I was quite impressed with the quality.The internal build quality was really nice, accounting for the relatively dated trough hole construction of course. The pots have a nice quality, the on-off and enable-disable switches feel really solid and passive cooling! No loud fans which is really great.The PL154 I bought from ebay had no shorting bars in between the front sensing terminals. I couldn't find them on a Dutch webshop so I decided just to email TTi and ask if they could send me some. To my surprise really they came back to me very quickly and I could even order a few new from knobs. No problem at all and for a really nice price!Once I got the parts, I send them an email to thank them about their service and asked them if a service manual was available. And within an our or so I had the Service Manual for the PL series in my mailbox! I was quite impressed by their service. Especially because I have a discontinued model...Don't know about this el-cheapo caps rumour in new models, but their service from my personal experience is great!

author: circlethecat
author_rank: Newbie
timestamp: November 02, 2012, 11:36:15 pm
content: OK, Lawrence and nack have done a nice job of describing why TTi supplies are really good kit. For a bit of fun, let me show you this piece of far eastern crap I was given to use at work last week, see attached pic.At first glance I thought this looks useable, at least the LED displays are bright and clear.For some reason the left hand channel is labelled as "channel 2" and the right as "channel 1", eh? Strange but no big deal.With the adjustment knobs at the side of the display, I found my hand could get in the way of reading the display while adjusting. So, right hand to adjust right channel, left hand for left channel. Hmmmm.It's a twin channel PSU but you can't disable them independently, both on or both off. WTF?With the output disabled (as shown in picture) the current readings are zero, not the current limit as you might expect - the only way to set the current limit is short the output and switch it on then adjust! You gotta be kidding me?Then, after 3 minutes of putting out something like 0.5W the very noisy cooling fan kicked in....that's when I flipped and went searching for our TTi PL303QMD-P.Good test gear just makes your day a bit nicer.

author: Soertier
author_rank: Contributor
timestamp: November 03, 2012, 07:11:12 am
content: I agree with good resolution meters, that is what attracted me to the QL355, which I want to buy. Seems different of some TTi power supplies because it has a fan, at least compared to the ones talked about in this thread.

author: T4P
author_rank: Super Contributor
timestamp: November 03, 2012, 01:09:14 pm
content: Most power supplies show current readings being shorted.AND caps whether or not it's from samwha it's still a BAD CAP. If it failed faster than a good japanese cap it doesn't mean it won't do the same thing in a Linear PSU what do you think it won't affect lifetime? IT WILL! A company that makes consistently bad caps will always make bad caps

author: tom66
author_rank: Super Contributor
timestamp: November 03, 2012, 01:16:05 pm
content: Quote from: circlethecat on November 02, 2012, 11:36:15 pmThe microcontroller lab at Uni has the same PSUs on each desk. One other defect they have: they blow fuses like nothing else. Seriously, turn it on and off more than about 10 times then pop! goes the fuse. Replace it and it works fine, clearly blowing due to inrush. Poor design. I do like the hundred clicks you get from the relays when you turn it off... wonder if there's any attempt to synchronise that so the output doesn't go high when turned off.

author: andys electronics
author_rank: Newbie
timestamp: November 03, 2012, 11:51:17 pm
content: i have a older version Thandar psu at work must be more than 15 years old now think its a TS3021, and has never given any problems, they are very stable, clean, highly accurate and well built.

author: mnm972
author_rank: Newbie
timestamp: November 06, 2012, 02:03:17 pm
content: Quote from: LaurenceW on November 01, 2012, 08:11:42 pmThanks for the info, The PSU was offered for 200~, It's a bit too much for me.I also learned about the diff between Analog and Digital PSU from thishttp://www.bkprecision.com/support/downloads/power-supply-guide.htmlThere is important info on the diff Analog/Digital Psu on:"Which is best: switching mode or linear?"section.Thanks for all for sharing.

author: Dagon
author_rank: Regular Contributor
timestamp: November 06, 2012, 03:16:15 pm
content: QuoteThat's a useful page for beginners.

author: Unknown
author_rank: Unknown
timestamp: November 06, 2012, 04:00:55 pm
content: Well after all that's been said, Thandar being of UK manufacture and now ageing, would be a very good buy if, you are or intend to use for development work, especially at low frequencies; why ! because digital SMPSU's create lot's of radiated pulsesthat will swamp any sensitive equipment, RF spectrum low to high... so, analogue is the way to go.

author: bingo600
author_rank: Super Contributor
timestamp: September 10, 2013, 11:27:49 am
content: I have a TTi PL310 beside my HP E3610 , and i think they are comparable in specs (ripple, regulation etc).I do like the "low profile" of the E3610 , but they cost 2x TTi price.I just bought 2 x TTi PL154 for 100€ , and look forward to get them.The PL series has even better specs than the TS series , and are excellent for OCXO testing./Bingo