Agilent E3648A PSU Schematic - Page 1
Forum section: electronics / testgear

author: gerrysweeney
author_rank: Regular Contributor
timestamp: April 09, 2013, 12:21:31 am
content: Hi All,This is a bit of a cheeky request, I am looking for a schematic for an E3648A PSU as I have a broken one. Normally I would buy the service manual on ebay but have been looking and there is none available. Could any one of you good folks help out?Thanks,Gerry

author: gerrysweeney
author_rank: Regular Contributor
timestamp: April 10, 2013, 05:04:11 pm
content: Anyone? please? %-B Any suggestion as to any other place I might go and look?ThanksGerry

author: eevblogfan
author_rank: Frequent Contributor
timestamp: April 10, 2013, 05:24:42 pm
content: heyI have got the schematic's but cant uploaded themplease dave let me only ones to upload big file to that thread or soI hope someone can input in here and light some thing ..P.S the menual is 6.7MB

author: free_electron
author_rank: Super Contributor
timestamp: April 10, 2013, 05:36:16 pm
content: agilent should have it for download on their site...

author: ve7xen
author_rank: Super Contributor
timestamp: April 11, 2013, 06:59:07 am
content: Quote from: free_electron on April 10, 2013, 05:36:16 pmThat goes without saying.They don't.

author: anotherlin
author_rank: Frequent Contributor
timestamp: April 11, 2013, 08:58:12 am
content: Do a search on google for "E3648A schematic". I've found it, I guess it's the same 6.7MB pdf file mentioned before.Otherwise, just PM me and I'll make it available for you.

author: eevblogfan
author_rank: Frequent Contributor
timestamp: April 11, 2013, 09:14:46 am
content: heyare you sure you found the full schematic ?I've searched and didn't found , although I do have the full schematic I've got from Shahriar ( which I thank him a-lot for that ! )

author: sorin
author_rank: Frequent Contributor
timestamp: April 11, 2013, 10:52:12 am
content: I have find this on web,hash: 015713E20AE230432F25B69A3BC81339I think that is the same.

author: anotherlin
author_rank: Frequent Contributor
timestamp: April 11, 2013, 01:11:29 pm
content: Yes, I think they are complete, the last pages have several pages of schematics along with components placement.

author: free_electron
author_rank: Super Contributor
timestamp: April 11, 2013, 02:18:17 pm
content: Read service notes to begin with. Loose caps !http://litstation.marketing.agilent.com/litapp/SearchSN.do?method=openExternalSNSearch&prodNum=E3646AAnd here is the manual with schematicshttp://ridl.cfd.rit.edu/products/manuals/Agilent/power%20supplies/E3646AE2.pdf

author: eevblogfan
author_rank: Frequent Contributor
timestamp: April 11, 2013, 07:02:12 pm
content: heyYup . thank you free electron , that's the menual I've got . thought Shahriar got that not from internet or soany how , it's good power supply and I hope some one will do full article about the design and the power circuit and loop calculations and so on . it might be you free electron ? or you dave ? or any other smart guy ?thank you in advance

author: gerrysweeney
author_rank: Regular Contributor
timestamp: April 11, 2013, 07:22:41 pm
content: Hi Everyone,I should have looked harder, thank you @anotherlin and @eevblogfan and @free_electron for the link, much appreciated, I have downloaded and it got me started.Unfortunately its not the loose caps, they seem fine but I will definitely re-solder them. The fault is more subtle on the channel 2 read back so I need to be poking around with the main board, and having stripped it down, the cables that connect the transformer and boards are too short to spread the think out on the bench so I have ordered connectors from farnell so I can make an extension.@eevblogfan I am doing a full teardown and repair video which I will post on my blog once done. Its an interesting fault so the video might even be interesting. I will do what I can to describe the PSU at a high level in the video - I recently done a similar thing on an Agilent E3634A which you can see here if you are interested:http://gerrysweeney.com/hpagilent-e3634a-power-supply-teardown-repair/Again, thank you all.Gerry

author: gerrysweeney
author_rank: Regular Contributor
timestamp: April 16, 2013, 07:43:43 pm
content: Hi Everyone,I put the schematic diagram to good use and repaired the PSU. I have documented the repair in a blog post for anyone interested:http://gerrysweeney.com/hpagilent-e3646a-power-supply-teardown-repair/Thank you all for your responses.Gerry

author: Huluvu
author_rank: Regular Contributor
timestamp: May 30, 2013, 06:21:28 am
content: Hi Gerry - just watched your Video - thumbs upResistors especially the precision SMD ones can easily damaged ore pre-damaged by only handling the PCB.This can happen during the manufacturing process and pass all the test and calibration processes.I know this, because we faced the same problem in our our factory while handling a very big Power supply with some precision resistors populated.The PSU's where tested and shipped out without any problem and after some days / weeks of operation together with vibrations from the end application the PSU failed.After very deeply investigation's and verification's we found that those resistors tends to have micro cracks and we changed the handling in our process to avoid any stress to the PCB.After that the problem solved.In your case this can also be explained by a single component failure, but as an conclusion for me (and a recommendation for everyone) I try to avoid any stress or bending while handling any PCB.Rgds Arne

author: TheDefpom
author_rank: Frequent Contributor
timestamp: September 28, 2018, 08:20:31 pm
content: Quote from: free_electron on April 11, 2013, 02:18:17 pmI just received a faulty one of these supplies, I will be doing a repair on it on my youtube channel, this thread was helpful !Just a small update to the quoted text above, the link for the service notes has changed, just substitute keysight for agilent:http://litstation.marketing.keysight.com/litapp/SearchSN.do?method=openExternalSNSearch&prodNum=E3646A