[SOLVED] Cheapest way, to 1kV - Page 1
Forum section: electronics / projects

author: andymcc
author_rank: Newbie
timestamp: May 01, 2022, 06:22:56 pm
content: Sorry if this is an FAQ. TBH this post is a bit of an impulse. I am mulling over my options for a quick and dirty, 1kV supply/reference, for testing purposes. The load is a 1Mohm voltage divider. With what I have lying about I can probably lash something up with a variable AC PSU unit and a transformer, rectifiers etc from the parts bin.Are there any cheaply available (used ex-corporate, ebay, china etc.) options that folks are using for this sort of thing ? The electroporesis units don't really go up to 1kV do they, unless there are.. hacks.. ?Edit: Erm.. I see this actually an FAQ, apologies.

author: magic
author_rank: Super Contributor
timestamp: May 01, 2022, 06:38:24 pm
content: QuoteProbably Cockcroft–Walton.A bunch of diodes and capacitors (not even rated for the full output voltage) plus some AC source a few times lower than the DC you want.

author: andymcc
author_rank: Newbie
timestamp: May 01, 2022, 06:55:02 pm
content: Thx.

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 01, 2022, 09:38:32 pm
content: Take a CCFL inverter and rectify the output. Run it from a variable bench power supply to adjust the output.

author: cdev
author_rank: Super Contributor
timestamp: May 01, 2022, 09:52:01 pm
content: I have some 120volt ionizer modules that output >1000v. They cost almost nothing.. They have spikes on their tops, I could photograph one for you. its just right downstairs, that would be easy.. let me know..I forget where I got mine.. some surplus seller.

author: Gyro
author_rank: Super Contributor
timestamp: May 01, 2022, 09:53:48 pm
content: Quote from: NiHaoMike on May 01, 2022, 09:38:32 pmYou'll need to bypass the series capacitor on the output of the inverter. Maybe use the footprint for the rectifier if it's T/H.

author: exmadscientist
author_rank: Frequent Contributor
timestamp: May 02, 2022, 06:52:34 am
content: If you are looking for something more "bench instrument" and less "weekend project", most Hi-Pot testers can do this. Just make sure you find one that can output DC (it's often an add-on option) and whose UI will let you create a test step that runs long enough to do what you want. And, as always with HV, mind the grounding (or not) of the outputs. A 1W load should be no trouble.This sort of thing is a fairly common use case for Hi-Pot equipment, so it is decently well supported, but every manufacturer's UI will be different. (They are also all bad.)

author: Someone
author_rank: Super Contributor
timestamp: May 02, 2022, 07:19:56 am
content: Quote from: andymcc on May 01, 2022, 06:22:56 pmWith correct spelling: electrophoresis, you might find more. As with any similar "high voltage" products past 1kV they become rather niche. High prices when new, and occasionally an amazing deal when someone needs to sell quickly.

author: Someone
author_rank: Super Contributor
timestamp: May 02, 2022, 07:22:53 am
content: Quote from: exmadscientist on May 02, 2022, 06:52:34 amSimilarly, megohmmeter or insulation testers usually have well regulated outputs. They were my go-to for a short duration test that needed a 1kV source.

author: Psi
author_rank: Super Contributor
timestamp: May 02, 2022, 08:28:53 am
content: Cheapest way to 1kv from parts laying around is probably 4x little junky low voltage iron core mains transformers, like 240V to 5V/9V/12V.Reverse them, wire all 4x 240V windings in series.Then parallel up the 5V/9V/12V windings .Feed the low voltage side with the speaker output from a generic audio amp playing a 50/60hz sinewave sound file. (Depending on the ohms you end up with you might want to put a resistor in series to keep the amp happy).Then add a some 1kV diodes on the output to turn it back to DC. Should get over 1kV DC, maybe 1.3kV.Or you could use less transformers and more diodes/caps to do voltage doubler/triplerBe safe though, 1kV is dangerous.

author: nali
author_rank: Frequent Contributor
timestamp: May 02, 2022, 08:45:09 am
content: If 12V > 1500V@1mA is any use I have one of these kicking around you can have for say a tenner incl postage? Unused, bought on impulse "that'll be useful one day". PM me if interested.https://datasheet.ciiva.com/4645/gma-301-4645200.pdf

author: Psi
author_rank: Super Contributor
timestamp: May 02, 2022, 10:22:22 am
content: At least with something like that there's some inherent safety due to it's power rating being 1.5W / 1mA @ 1500V.But i'd still want to do some tests loading it down to 100V and seeing what sort of current it can source absolute max before id trust being too casual around it.

author: Someone
author_rank: Super Contributor
timestamp: May 02, 2022, 11:50:34 am
content: Quote from: Psi on May 02, 2022, 08:28:53 amNot a great idea as most mains transformers like those are not designed to float/isolate more than their rating, expecting both sides to be earthed.

author: Psi
author_rank: Super Contributor
timestamp: May 02, 2022, 12:04:01 pm
content: Quote from: Someone on May 02, 2022, 11:50:34 amDidn't say it was a great idea, just that it was the cheapest one.

author: themadhippy
author_rank: Super Contributor
timestamp: May 02, 2022, 12:49:11 pm
content: Quoteor wire a dc motor in series with the primary's and power from a lantern battery

author: nali
author_rank: Frequent Contributor
timestamp: May 02, 2022, 12:55:22 pm
content: Quote from: Psi on May 02, 2022, 10:22:22 amOut of curiosity I thought I'd measure it with a couple of resistors I had convenient as loadsNo Load - 1580V1 Meg - 1360V150K - 90VI also noticed it states "output proportional to input" on the DS, so I guess it can be used with a feedback loop.

author: Psi
author_rank: Super Contributor
timestamp: May 02, 2022, 01:00:11 pm
content: Seems relativity safe then.So long as no one adds an output capacitor.

author: oz2cpu
author_rank: Frequent Contributor
timestamp: May 03, 2022, 07:15:44 pm
content: here is a nice regulated wayhttps://youtu.be/WPruls5KfbQuse english subs