Which used calibrator to put the hands on? - Page 1
Forum section: electronics / general

author: branadic
author_rank: Super Contributor
timestamp: February 27, 2019, 08:19:24 pm
content: In case you have a limited budget and should by a used dc voltage calibrator of ebay, what would you choose and why? I found:- Fluke 322A- Fluke 335D- Fluke 343A- Fluke 3330BAre there other units to look for?-branadic-

author: grizewald
author_rank: Frequent Contributor
timestamp: February 27, 2019, 09:33:18 pm
content: I'd actually like to see any of those devices at something close to a realistic price from any EU seller.Getting one from the USA and having to ship it via courier to avoid the black hole that is Postnord's customs handling makes it prohibitively expensive.

author: Conrad Hoffman
author_rank: Super Contributor
timestamp: February 27, 2019, 09:41:37 pm
content: What do you actually want to do with it? Some of those old Flukes are real boat anchors. I gave one away because it really didn't offer anything special compared to a small voltage source, save for the 1000 V range, and it took up too much space and weighed a ton. Some of the others are more versatile, but it all depends on the application.

author: beanflying
author_rank: Super Contributor
timestamp: February 27, 2019, 11:25:47 pm
content: I just did a similar exercise with DC Calibrators, my conclusion was 332D (no Null meter) or 335D purely on specs in the end I got a 335D as a pristine one turned up in Australia instead of paying $3-400USD for shipping. Have a careful look at the other Fluke offerings specs and you really need to move up to one of the 'newer' Multifunction units to get a better result.I do own a Valhalla AC Calibrator and I was fairly keen on getting a matching DC (2701) one of theirs but the spec wasn't flash compared to the 332/5D.eBay auction: #301075692003The EDC ones if you want to do it on a budget are an option and also fairly affordable to ship due to a smaller form factor and lower weight than the flukes but if it is just based on just on specs it's a no.eBay auction: #123649408131The HP 740B I own is another to keep an eye out for but getting a bag of rocking horse poo is more likely especially if you want one with the input and output boxes. These are 2ppm while the Fluke 332/5D are 1PPM.Buy a real Anchor you know you want too

author: w6te
author_rank: Newbie
timestamp: February 27, 2019, 11:30:12 pm
content: A Fluke 5100B will generate a calibrated source for AC, DC, Ohms and Amps (AC & DC). They can be picked up for a few hunderd dollars.

author: beanflying
author_rank: Super Contributor
timestamp: February 27, 2019, 11:41:14 pm
content: Quote from: w6te on February 27, 2019, 11:30:12 pmI think you may have slipped a decimal point. I haven't seen one that works for under 1k USD?

author: DC1MC
author_rank: Super Contributor
timestamp: February 28, 2019, 12:14:28 am
content: Right now there are a couple of good looking 5100B's from Poland on the Germanbay, the sad story is they are ca. 2.2K EUR each.I still hope that someone around Mannheim will ever be willing to share some time on his calibrator, the structural integrity of my little apartment will be seriously affected by such a beast, not to mention the damage will do to my bank account integrity.On the other side, I have a fey pieces of TE crying silently for calibration, so it's tough call.Good luck,DC1MC

author: beanflying
author_rank: Super Contributor
timestamp: February 28, 2019, 06:47:16 am
content: Was below Caffeine functionality levels a while back with my earlier post and forgot to mention this baby Fluke 515A Calibrator.I have had it on all day and it has remained within a few PPM at worst from 20-35C against the 335D while the 34401A has done it's normal 1-2PPM/5C (5 flicking 6 PPM) rise over that time.Just a thought if you want to calibrate other lower spec meters to say 4 1/2 digits. Bit of a rare bare but it will do 100V AC, DC and R over select ranges and does have a battery option if you can find one fitted. Mine was only $200'ish from a local evilbay Auction.Add a Hamon Divider to the front end and away you go.

author: e61_phil
author_rank: Frequent Contributor
timestamp: February 28, 2019, 08:34:18 am
content: I would search a Fluke 5440B. I had two 343A before and the 5440B is a complete other class. It's linearity is really good and it is remote controllable.Linearity adjustment of these old Fluke ones with dials is a real pain.

author: branadic
author_rank: Super Contributor
timestamp: February 28, 2019, 04:25:21 pm
content: They are almost located outside EU and shipping is quite expensive. What to say about Datron 4000A?-branadic-

author: DC1MC
author_rank: Super Contributor
timestamp: February 28, 2019, 05:33:49 pm
content: Quote from: branadic on February 28, 2019, 04:25:21 pmNoooo, not that one, the seller will accept 1k and then what I will dream about !!!I was looking for a long time at it onbay, but didn't get 1K available, I hope you get a nice unitif you choose to get it.But for the Polish ones, the 30EUR shipping it's not that much, it's the 2K+ price that hurts.Cheers,DC1MC

author: alm
author_rank: Super Contributor
timestamp: March 03, 2019, 03:05:52 pm
content: Quote from: beanflying on February 27, 2019, 11:25:47 pmI think you're off by an order of magnitude there. The Fluke 332/5D is specified as 10 ppm basic accuracy over 60 days.Quote from: grizewald on February 27, 2019, 09:33:18 pmDoes the eBay global shipping program ship to Sweden? For all it faults, it moves the burden of the customs paperwork and fees to eBay, so that may help in your case.Quote from: DC1MC on February 28, 2019, 12:14:28 am2.2k EUR for a 5100B is ridiculous in my opinion. Waiting for one to pop up on US eBay for $1k and shipping that should be cheaper. And even $1k is expensive in my opinion. That's similar to a Fluke 5440B, which, though it is less versatile (only DCV, no ACV, current, resistance), is in a different league in accuracy and linearity.From this list in the first post, the Fluke 335D has the best specs, but it is a boat anchor and from what I've read somewhat of a bear to maintain. The older ones have a mechanical chopper. Later versions had a FET chopper.Here is an alternative circuit that should perform better.Some lighter calibrators are the Valhalla 2701B/C (quite close in specs, but from what I've read not as stable in real-life) and Data Precision / Analogic 8200. Shipping these from the US can be quite affordable. Don't get fooled by "buy it now" prices. If you're patient, you should be able to find much lower prices. For example, I see a Data Precision / Analogic 8200 that recently sold for $300, and also a Valhalla 2701B for $300. That is a similar to what the Fluke 335D usually sells for, but shipping should be much cheaper.The Datron 4000A is much more modern than the analog Fluke calibrators, has better specs and can be fitted with optional resistance and current functions. Not sure how repairable they are.

author: e61_phil
author_rank: Frequent Contributor
timestamp: March 03, 2019, 03:15:21 pm
content: I repaired a data precision 8200 last year. I would stay away from such a unit. It is very simply build, but the linearity is very bad.

author: Conrad Hoffman
author_rank: Super Contributor
timestamp: March 04, 2019, 04:18:26 pm
content: I have to disagree on the 8200. I've had one for years and it's both stable and linear. Reliability has been good, save for one flaw. The encoder switches get dirty and don't work as predictably as they should. It's not a show stopper, and they can be cleaned, but replacement is the best answer. I wouldn't pay a huge amount of money for one, but it's one of the most useful things on my bench. Just wish I had the GPIB option for it.

author: grizewald
author_rank: Frequent Contributor
timestamp: March 04, 2019, 06:21:57 pm
content: Quote from: alm on March 03, 2019, 03:05:52 pmSome do and some don't. The problem is that even using the GSP doesn't really help to get the prices within a reasonable area. For example, there's a Fluke 731B in the USA listed for $420 that ships with GSP. The shipping cost is $55 and the import charges $122 for a total of $597, which isn't worth it.Likewise, there's a 5100B for $1050, but shipping with GSP is $468 with import charges of $363.I'm resigned to my chances of buying any kind of useful calibrator being "slim to none".

author: e61_phil
author_rank: Frequent Contributor
timestamp: March 04, 2019, 06:35:38 pm
content: Quote from: Conrad Hoffman on March 04, 2019, 04:18:26 pmDo you have some measurements of the linearity? Unfortunately I can't find measurements to my unit. Mine had the GPIB Interface, but the linearity was the cause of selling it. It tried several times to adjust it, but it wasn't possible. But I never expected such a good performance from the design of the DAC.

author: Conrad Hoffman
author_rank: Super Contributor
timestamp: March 04, 2019, 09:07:31 pm
content: No numbers, but I have a couple decent KVDs (Julie & ESI) and did a direct comparison with those. It matched them within a couple counts over the 10 V range, which is really the limit of the KVDs. I do remember having one of the close tolerance 1 kohm resistors go bad. Replaced it with a Vishay foil and no further trouble. IMO, the performance of the unit is highly dependent on the quality of the parts making up the DAC. Obviously it's also only as good as the adjustment of the summed sections and I don't have anything like a 7.5 or 8.5 digit meter to make the job easy.

author: e61_phil
author_rank: Frequent Contributor
timestamp: March 04, 2019, 09:38:39 pm
content: A couple of counts means a couple of ppm FS. On a 5440B for example we have more than an order of magnitude less INL.The DAC is a simple divider string with lots of 4051 muxers. For such a design the INL isn't bad.

author: branadic
author_rank: Super Contributor
timestamp: March 05, 2019, 07:54:27 am
content: QuoteI'm so sorry.-branadic-

author: RobK_NL
author_rank: Frequent Contributor
timestamp: March 05, 2019, 09:25:43 am
content: I happen to know there's this guy in The Netherlands who wants to get rid of a 5101B and two 5440B's ...They were in working condition last time I checked, but that's, eh, "some time ago"I'll need a bit of time to dust them off and check them out, but I'm hellish busy at the moment, so that will be late March, early April or so.Oh, and for those interested: there's a 5220 and a 5450 as well.Rob

author: beanflying
author_rank: Super Contributor
timestamp: March 05, 2019, 09:33:04 am
content: And all the Europeans in 'need' of Calibrators go

author: RobK_NL
author_rank: Frequent Contributor
timestamp: March 05, 2019, 09:38:05 am
content: I'mnotgoing to give a refund on any device that's full of drool. Just so you know

author: DC1MC
author_rank: Super Contributor
timestamp: March 05, 2019, 07:59:17 pm
content: Quote from: branadic on March 05, 2019, 07:54:27 amIt's gone now, did you get it, how much?!?!Cheers,DC1MC

author: grizewald
author_rank: Frequent Contributor
timestamp: March 05, 2019, 09:39:23 pm
content: Quote from: RobK_NL on March 05, 2019, 09:25:43 amTwo 5440Bs?!Guess I'd better get saving some krona and hope.

author: beanflying
author_rank: Super Contributor
timestamp: April 01, 2019, 12:29:22 am
content: Slightly obscure all in one Calibrator to add to the list of possibilities. Rotek 710http://rotek.com/dismodel710.htmlI turned it up looking for something similar yesterday. Not the worlds greatest specs for 6 1/2 and up but very usable for a lab transfer standard.It was on evilbay Germany and sold a few hours ago for 350 Euro. Should have maybe gone to one of the nearby thread posters here I passed it on to but they had a Gixen failure

author: ArthurDent
author_rank: Super Contributor
timestamp: April 03, 2019, 03:17:29 am
content: Reading all this reminded me I have a COHU 355 standard that I've been planning to repair for a few years and I'm now inspired to check out the problem. It was working fine then just stopped so I don't think it is a major problem. Here are the specs on the unit which are a little hard to find. I have the manual so I have a chance of finding the problem.

author: Solodolo47
author_rank: Newbie
timestamp: March 04, 2024, 01:43:44 am
content: Hello would you be able to send me a copy of the manual? I have just acquired a 355 and I have half of the manual. I really need the calibration portion of the manual.