Initial Equipment for an Academic Power Electronics/Drives Research Lab - Page 1
Forum section: electronics / general

author: magicsmoke
author_rank: Regular Contributor
timestamp: August 04, 2013, 06:12:13 am
content: I need to purchase some initial equipment for an academic power electronics/drives research lab (in the U.S.) ASAP. The lab will primarily be performing research in the area of electric drives, electric machines, and power electronics. Most of drive and power electronic work will be with 208 Vll-rms line inputs (~300 V DC links) though there will be some test setups with 460 Vllrms connections (~650 V DC links). The power range of the test setups will range probably from ~100 W to ~30 kW. The drive and power electronics development will be at both the signal and power level.The already purchased equipment isYokogawa DL850V Scopecorder and input modules (great for mechatronics and power electronics debugging)Yokogawa high voltage differential probesYokogawa current probesYokogawa WT1800 power analyzerThe criteria I have been mentally using to select equipment are:a) Price to performance ratio - The budget is somewhat limited but equipment that performs well for research is also important.b) Longevity – There probably won’t be much of a chance to purchase new equipment for many years.c) Robustness – The equipment will primarily be used by grad students who I am sure will find ways attempt to destroy it.d) Ease of use – Hopefully the grad students won’t have to spend huge amounts of time figuring out how to use a piece of equipment.I have been leaning towards mostly Agilent test equipment as that is what I have used primarily in the past and I have very little time to research other options.The equipment that I am leaning towards so far is the following:Scope (2nd):Agilent 3054X===================More expensive than I would like but very nice.Benchtop DMM: Agilent 34401A========================I am actually not sure how much this will be used compared to the portable DMM. Maybe could get away with a cheaper model. This model also might be EOL.Portable DMM: Fluke 177, Fluke 87 V, (Fluke 289?)====================================The Fluke 289 might be more than is really needed. I might just get a few 177s and one 87V. Other than the Agilent any other recommendations? How serious should I consider Brymen or others?Function Generator: Agilent 33210A===========================Benchtop DC Power Supply: Agilent E3630A, Agilent E3631AI don’t have much of an opinion on benchtop power supplies. Are there some other brands/models that I should consider that are a better bang for the buck (Agilent U8000 series)? I will need to get more of these so a cheaper option would be appreciated.LCR Meter: Agilent 4263B====================I would prefer the E4980AL but it is significantly more expensive. The 4263B seems like it might be EOL too. The test leads for both LCR meters are separate expensive orders. One other LCR meter that I have been considering is the Hameg 8118; any thoughts on it? I have never used Hameg equipment.Variacs: Staco Energy various single and three phase models.============================================Maybe Superior Electric/PowerstatSolder Station Equipment:===================Hakko FX-888D (Maybe a Weller instead)Hakko Chisel Tip 2.4 mm T18-D24Hakko Chisel Tip 1.6 mm T18-D16Hakko Fine Point Tip 0.2 mm T18-BLHakko 611 Solder Spool ReelElectrolube Flux PenMulticore SolderMulticore Solder WickPanaviseSolder Sucker Pump (Any brands to look for?)Anti-static pad and strap (Any brands to look for?)Microscope (I would love a Manta but it is probably to expensive; any other recommendations?)Everything look ok for the solder station equipment? Where is the best place to buy solder station equipment?Large DC Power Supply: Multiple options under consideration including the following.==============================================================Agilent 6035A (I have used this in the past but would like something higher power)Agilent N8700 Series (Has anyone used these?)Magna-Power DC SupplySorensenAny recommendations?A few pieces of equipment I have no idea about so any recommendations would be appreciated:- Crimping tools- Hot air rework station- Circuit breadboard (Any good quality options)- Optical tachometer- Storage cabinets for test equipment- Storage drawers for electronic componentsAny alternative equipment recommendations that I should check out? Anything major I am forgetting other than hand tools, etc.

author: BravoV
author_rank: Super Contributor
timestamp: August 04, 2013, 06:29:53 am
content: Just curious, which scope is that ?

author: jeremy
author_rank: Super Contributor
timestamp: August 04, 2013, 06:43:06 am
content: I have a lab for academic/semi-commercial use that was self-funded, so money is very important. Although my work is the opposite end of the spectrum (literally): high frequency, ultra low power.MM: I have a 34405A, thing is a beast. I'm very happy with mine, I imagine the 34401A is similar.Why no clamp meters?PSU: You could save a lot of money buying ATTEN or similar benchtop supplies. I have an ATTEN triple output, cost me AU$250 and works just as well as the agilents I have used. The technical colleges around me (TAFE for you aussies!) really love these units.http://www.triosmartcal.com.au/dc-bench-supplies/2432-atten-aps3003s-3d-dual-power-supply-0-30v-3a.htmlLCR: do you absolutely need 100kHz? Coming down to 10kHz will save you a lot of money. I have also sometimes found that when people need more than 10kHz, they need a *lot* more than 10kHz (meaning that you should be using a network analyser, not an LCR). Also using an LCR is surprisingly difficult if you want good accuracy; do the grad students have experience in this? the ones I know don't. Sorry, don't know your background but have seen people thinking that measuring L and C is as easy as measuring R and wasting their money. It ain't.soldering: I have the Weller WD1 + 80W iron + WMRP pencil. Worth every cent. Picked mine up from digikey. Also might want to add liquid flux depending on your work, sometimes you just need a ton. Also lots of isopropyl alcohol/isopropyl wipes for cleaning, you can never have too much!microscope: I have an olympus stereo that I picked up off ebay for $150. Have soldered for 5-6 hours with no problems. The question is really are you going to be using it to solder every day? if yes, buy the mantis. If no, get a cheaper one.breadboards: basically all the same quality in my head. Sparkfun ones are nice nonetheless.

author: magicsmoke
author_rank: Regular Contributor
timestamp: August 04, 2013, 06:49:11 am
content: Quote from: BravoV on August 04, 2013, 06:29:53 amThe main scope (not exactly a scope) for power electronics development is a Yokogawa DL850V Scopecorder. It is great for this type of work because of the high channel count (up 16) and high voltage isolation. May also get a Agilent 3054X or a less expensive model.

author: magicsmoke
author_rank: Regular Contributor
timestamp: August 04, 2013, 06:57:10 am
content: Quote from: jeremy on August 04, 2013, 06:43:06 amI have purchased some current probes (very expensive unfortunately). At higher current levels I generally build my own boxes with LEM sensors for measuring output current.Quote from: jeremy on August 04, 2013, 06:43:06 amThanks for the recommendation.Quote from: jeremy on August 04, 2013, 06:43:06 amI do need more than 10 kHz for measuring power magnetic components and bus cap properties. Actually I would prefer slightly more than 100kHz but it gets much more expensive. The grad students don't have experience in this so I suspect I a lot of time will be spent with them.

author: free_electron
author_rank: Super Contributor
timestamp: August 04, 2013, 06:59:56 am
content: Why an lcr meter ? Especially such an expensive one ? Get a handheld one and use the remaini g money to buy better soldering equipment than'crappo'Tha same for the function generator. Why do you need that ?Now, if you are going to be mucking around with power conversion i strongly suggest you look at a power analyser... Imstead of having to do all the crap work by hand , those machines will give you much faster results. Look at the power analysys package for the agilent 4000 series scopes.For high power power supplies : xantrex or sorensen (actually the same thing)

author: magicsmoke
author_rank: Regular Contributor
timestamp: August 04, 2013, 07:12:05 am
content: Quote from: free_electron on August 04, 2013, 06:59:56 amAlready have the power analyzer, Yokogawa WT 1800. It is great for inverter and motor efficiency measurements. In my experience the scope power analysis packages are not very useful for anything three phase.Quote from: free_electron on August 04, 2013, 06:59:56 amThe handheld ones I have looked at don't seem to operate at higher frequencies. The fundamental switching frequency can easily be between 10 kHz to 100 kHz. The response of power magnetic components needs to be characterized for both the fundamental and higher frequencies. For DC link caps it is very useful for checking where they cross-over into an inductive characteristic. Also for measuring ESR. Any recommendations for hand held LCR meters I should check out?Edit: Just took at look at the Agilent LCR meter page again and it does look like they have one handheld which goes to 100 kHz. I am a little concerned that they don't seem to use a 4 wire Kelvin connection though. Will have to check the spec sheet on this one.Quote from: free_electron on August 04, 2013, 06:59:56 amJust useful lab equipment for checking and debugging signal conditioning circuitry. Occasionally, for testing op-amp circuits, ADs, etc.

author: plesa
author_rank: Frequent Contributor
timestamp: August 04, 2013, 08:21:10 am
content: Contact Agilent representative and ask him for quotation ( give him the list of instruments and the ammount of $$$ which you have). I highly reccommended their demo units. They are cheaper with fully warranty and with lot of options.Benchtop DMM: buy the newest model 34461A it is cheap and has more features than 34401ADMM : Buy two or more Fluke 87 VFuncGen: Take into account the availability of free function generator an various oscilloscopes, such as 3000X and etc.Power Supply: It is good choice, available with free U1272A multimeter ( probably only in EU region)LCR : As Free_Electron mention the LCR meter E4980A ir overkill, it is 20k beast quite noisy. I rather use U1733C for everyday work and the E4980A is under my bench. Benefit of 4980 is the bias voltage and amplitude control and manual frequency settings.Soldering: chemitronic wick, Panavise I will buy whole their catalog if I can ;-) PAce soldering stationFor high power supply I have good experiences wih Delta-Elektronikahttp://www.delta-elektronika.nl/, but it is EU company and i'm not sure about availability in US.Ask all lab members to create list of instrumnets which they individually needs with respect to maximal ammount of $$ to help you to set priorities.

author: EEVblog
author_rank: Unknown
timestamp: August 04, 2013, 09:00:23 am
content: You will likely need a bunch of HV differential probes, like:http://teledynelecroy.com/probes/probemodel.aspx?modelid=24&categoryid=3&mseries=430

author: ddavidebor
author_rank: Super Contributor
timestamp: August 04, 2013, 10:32:14 am
content: It's all ok but not the soldering station.I've worked in a power electronic company and the hakko cannot simply do it.You need o a very big (100+w) standard iron or a JBC.Brymen do really good and safe multimeter, you should buy them.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: August 04, 2013, 11:53:43 am
content: For high power stuff you might want to consider a low-end thermal imaging camera.Definitely need a meaty iron - JBC or Metcal. And probably more than one of them.Also a good heated vacuum desoldering tool for desoldering plated groundplanes/multilayer boards - the Metcal one is excellent, not sure if JBC have an equivalent.The Aim-TTi I-prober is probably also worth putting on the list.Func (/arb) gen look at the Rigol DG4000 series. Arb probably more useful than plain funcgen for power stuff.For routine stuff like bench PSUs you can probably spend less than Agilent prices

author: KJDS
author_rank: Super Contributor
timestamp: August 04, 2013, 12:44:21 pm
content: I'd go with Metcal for the soldering, they're better at big stuff than any of the others. I love the finesse of a JBC for small SMD work but Metcal are better at delivering a lot of heat onto big items and will also be more robust in the hands of students.

author: free_electron
author_rank: Super Contributor
timestamp: August 04, 2013, 03:36:50 pm
content: Aim tti prober. YesHigh voltage diff probes like the tektronix onesSince you aregoing to bemucking around with inductors and caps trying to optimize switchers : forget the lcr bridge. Get an impedance analyser. That is what you need as it extracts the entire curve over frequency. Get the biassing splitter and you can see what the parts do in real life.I am doing power converters (well , not 'power' ) 12, 5 or liion in and 1.2 to 0.8 out multiphase , very high switching frequencies . To design the silicon we need to know the behavior of the parts... Out comes the 4395 network analyser with impedance analyser installed.

author: tom66
author_rank: Super Contributor
timestamp: August 04, 2013, 03:38:39 pm
content: I would also get a variac, isolation transformer and high power load resistors ideally adjustable ones (rheostats.)

author: magicsmoke
author_rank: Regular Contributor
timestamp: August 04, 2013, 07:34:28 pm
content: Quote from: plesa on August 04, 2013, 08:21:10 amI agree the 34461A does look better thanks for the tip.Quote from: plesa on August 04, 2013, 08:21:10 amI am considering getting a 3000X scope in addition to the Yokogawa Scopecorder that was already purchased. How is the functionality of the internal function generator in the 3000X compared to an Agilent 33210A?Quote from: plesa on August 04, 2013, 08:21:10 amI am not considering the E4980A (~$17K) but the 4263B(~$2.5K) or E4980AL(~$4.5K) and maybe now the U1733C. The E4980A is out of my price range.Quote from: EEVblog on August 04, 2013, 09:00:23 amAlready have some Yokogawa high voltage differential probes though I don't particularly like the form factor. The Yokogawa scope inputs are also isolated up to 650V or 1000V. Agilent used to make some high voltage differential probes that I liked the form factor butQuote from: mikeselectricstuff on August 04, 2013, 11:53:43 amI was looking at some of the cheaper FLIR cameras. It beats having to stick thermal couples over everthing.Quote from: mikeselectricstuff on August 04, 2013, 11:53:43 amWe had a couple of Metcals at one of my industry jobs and I never really noticed much of a difference compared to some bog standard Wellers we had. Are they really worth the difference in price?Quote from: mikeselectricstuff on August 04, 2013, 11:53:43 amThanks for the recommendation it looks useful.Quote from: mikeselectricstuff on August 04, 2013, 11:53:43 amAny particular brands or models you would recommend? Pretty much all the previous industry jobs and labs I worked at just had Agilents.Quote from: free_electron on August 04, 2013, 03:36:50 pmI agree the impedance analyzer would be nice but I think they are outside of my price range. The 4395 network analyser looks nice but it is discontinued and there doesn't really seem to be an equivalent Agilent model for roughly the same frequency range for a reasonable price.Quote from: tom66 on August 04, 2013, 03:38:39 pmAlready planning to get some Staco variacs. Already have some fixed power load resistors. Any recommendations for power rheostats?

author: magicsmoke
author_rank: Regular Contributor
timestamp: August 04, 2013, 07:45:19 pm
content: Any particular Metcal and JBC models that I should consider?