Fluke 5440B replacement - Page 1
Forum section: electronics / general

author: e61_phil
author_rank: Frequent Contributor
timestamp: October 10, 2018, 05:47:23 pm
content: Hi,our Fluke 5440B at work died and it seems to be quite hard to find a "new" one these days.Most of the time, the unit was used a a stable source for 5V, 10V, 625V and 1000V in both polarities.I looked for a Fluke 5720A, but the service period will end next year and we don't want to spend 30k€ for a unit which can't be repaired in two years or so.A Fluke 5730A will start over 60k€ and is quite pricey as a replacement of the Fluke 5440B which costs 2k5 two years ago.A Fluke 5522A is still quite pricey and its stability is only 3ppm over 24h at 1000V. That is far too much. The 5440B was specified with 0.5ppm and that is what we need.Does anyone know another calibrator which has comparable stability to the 5440B and is available on the market? If the costs are above 10k it should also be serviceable.ThanksPhilipp

author: Dr. Frank
author_rank: Super Contributor
timestamp: October 10, 2018, 05:59:28 pm
content: Rainer-foertig.de still lists a 5440B for 1899€.What about repair, by you capable volt-nuts?

author: HighVoltage
author_rank: Super Contributor
timestamp: October 10, 2018, 06:24:40 pm
content: The cal lab I have been using officially here has 3 Fluke 5730AWhen I asked him about the 60k euro price tag, he said that it is just an inflated list price.So may be you can negotiate the price dramatically.

author: e61_phil
author_rank: Frequent Contributor
timestamp: October 10, 2018, 08:12:04 pm
content: Quote from: Dr. Frank on October 10, 2018, 05:59:28 pmI found many pages with used stuff, but I wasn't aware of Rainer-Foertig. Thanks!!Quote from: HighVoltage on October 10, 2018, 06:24:40 pmInteresting! I'm already in contact with CalPlus...

author: Mr. Scram
author_rank: Super Contributor
timestamp: October 10, 2018, 09:44:07 pm
content: Out of curiosity, what does it approximately cost to have one of these Fluke 5440Bs calibrated?

author: MadTux
author_rank: Frequent Contributor
timestamp: October 10, 2018, 10:11:01 pm
content: Get a second 5440B so you can swap boards for quick diagnostics.Apart from that, these instruments have good stability, have few custom parts inside and full schematic is available, so I wouldn't change unless you absolutely have to. Don't think that new calibrators are that serviceable, much more custom parts and usually no schematic.

author: RobK_NL
author_rank: Frequent Contributor
timestamp: October 11, 2018, 07:21:40 am
content: I have two 5440s I want to part with. PM me if you're interested.

author: e61_phil
author_rank: Frequent Contributor
timestamp: October 11, 2018, 07:26:07 am
content: Quote from: MadTux on October 10, 2018, 10:11:01 pmThis is what I've done at home. But this question here is for a replacement in the company. And Fluke will hopefully service the 5730A the next years.Nobody here in the company will repair these units by themself (that doesn't make sense economically).Quote from: RobK_NL on October 11, 2018, 07:21:40 amI will do so

author: MadTux
author_rank: Frequent Contributor
timestamp: November 22, 2018, 10:15:57 pm
content: Recapping the inguard PCBs makes them much more reliable.Just resurrected my 2th 5440B by just recapping the inguard regulator board (last board in the back).It had random "inguard bus failure" fault or something, especially during warmup, when it needed most power.Almost all electrolytics in the inguard section have really bad ESR in my units, especially the yellow 22uF/50V ones. Capacity is more or less fine, but ESR is really bad, 1++ Ohm usually. I'm currently in the process of recapping all inguard boards with better, larger capacity electrolytics to fix them completely.3th 5440 has display problem and also problem with PSU and power distribution on backplane, backplane connectors got damaged during shipping some times in the past, probably because heavy transformer wasn't attached with screws. But shouldn't be too hard to fix once I have 2 working ones.

author: ManateeMafia
author_rank: Frequent Contributor
timestamp: November 22, 2018, 10:29:14 pm
content: This is my current project. I have been chasing +5v issues in the inguard section. It appears a leaky capacitor has caused some corrosion on that same regulator board. Some cleaning has been successful but I need to deep clean that area. My cap order showed up yesterday and will be performed tomorrow. I still have inguard comm errors that seem to be related elsewhere but I hope this will clear it up the +5v rail for a while.I think I will change the 5 optocouplers on the guard crossing pcb for good measure.The unit had no errors when I got it a few years ago but was never fully tested and now it is sitting on the bench.