Shopping for a 500-1000VDC Lab Supply - Page 1
Forum section: electronics / testgear

author: SmallCog
author_rank: Frequent Contributor
timestamp: March 04, 2020, 09:41:59 pm
content: Firstly, apologies if this is in the wrong place or been extensively covered... I've done some searches but it all seemed to be related to home made supplies or multimeter calibrators.I find myself in need of a high voltage DC source for testing some gear at work and my existing 250VDC supply just isn't quite enough.For health and safety reasons DIY is not an option, the supply needs to be something off the shelf, preferably from an Australian retailer. Realistically it doesn't need infinite variability and could even just be a single fixed voltage.I'm thinking 1000VDC would be nice to have. Currently the most I need is 800VDC but I could make do with 500VDC if I had to. Realistically 50mA is probably enough for what I'll be doing at the moment but more current makes it more useful for things that haven't come across my bench yet.Under $2000AUD is the target budget. The cheapskate in me already tried doing it with a megger but the trusty yakogawa just didn't have enough mAMy googling has found these options:500VDC 1A - not a brand or retailer I'm familiar with and I've not found any reviewshttps://www.amazon.com.au/Regulated-Precision-Adjustable-Power-Digitals/dp/B07QVKCRVK500VDC 50mA - I like that it's made in Australia, not much is any more...https://www.wiltronics.com.au/product/6166/iec-high-voltage-laboratory-power-supply/Above 500V seems to jump straight out of my budget, but I'm hopeful someone here may have some suggestions?

author: beanflying
author_rank: Super Contributor
timestamp: March 04, 2020, 10:22:14 pm
content: One option to consider is used Electrophoresis Power Supplies. Not so common secondhand in Oz but plenty in the USA some very cheap. Worst case is you will need to run a stepdown transformer as well and while that is a bit of a cludge they are handy to have around for possible other bits of US sourced gear.Evilbay listings are vague with generally not much in the way of specs so you will need to do some leg work or do the rounds of the local medical/scientific secondhand dealers locally.

author: SmallCog
author_rank: Frequent Contributor
timestamp: March 05, 2020, 04:55:13 am
content: Quote from: beanflying on March 04, 2020, 10:22:14 pmUnfortunately I need to buy new/local but I've hit up Thermo for a quote on their offerings, such as:https://www.thermofisher.com/order/catalog/product/EC1000XL?SID=srch-srp-EC1000XL#/EC1000XL?SID=srch-srp-EC1000XLAnd found these ones on the google as well, also requested a quote:http://adelab.com.au/electrophoresis-tank-power-supplies/biocom-electrophoresis-power-suppliesFingers crossed the prices are reasonable.

author: beanflying
author_rank: Super Contributor
timestamp: March 05, 2020, 05:03:00 am
content: I ran across them as a possible source some time ago and while they may not suit everyone the pricing is better than some of the Typical test gear brands. I think that Fischer one you linked was a bit over $2k USD as I bumped into a price this morning when checking my poor spelling with googleThere has been plenty of threads here about people wanting to build HV supplies from scratch but I can't think of any that got to satisfactory completion someone else may have a link)But for this sort of thing OH&S and HV are an issue if it goes wrong.Let us know what sort of prices you get back too.

author: SmallCog
author_rank: Frequent Contributor
timestamp: March 31, 2020, 10:21:36 pm
content: Quote from: beanflying on March 05, 2020, 05:03:00 amPrices are a bit hard for me to publicly post due to where I work...I have however ordered a 1200VDC supply that was more than I hoped to spend, but significantly less than it would have been if I'd just bought the first one I saw...Most of the (brand new, retailed in Australia) electrophoresis supplies I looked into had biology lab features that limited their usage for my purpose without bodging stuff. Issues I encountered were things like shutdown or not start up if the load was too low, and shutdown if the load changed mid experiment. These are probably handy things for nerds that dissect frogs and electrify jelly but would have gotten in my way.Some models had the ability to turn these failsafes off, but some don't.

author: ArthurDent
author_rank: Super Contributor
timestamp: April 01, 2020, 06:34:34 pm
content: I bought a nice used 1000VDC supply (photo below) for less than $100USD and some of the 'features' these supplies have can be a problem for general use as you say. I was using my supply to power a tube type radio receiver and when the audio level changed the supply would shut down because it sensed a change in load resistance. It also would shut down if there was no load as well. Some of these problems could be easily worked around by having a resistor load that draws just a few Ma or a capacitor across the output to fool the supply but those are features I'd rather not have in a power supply. I haven't checked for ripple/noise on the output because that probably isn't something that would be important in these supplies but the one I bought seems to be very well built.

author: AVGresponding
author_rank: Super Contributor
timestamp: April 01, 2020, 07:58:47 pm
content: In general I'd say the older the design the better, for general electronics use when it comes to EP supplies, but this is unlikely to be a viable option for someone buying equipment for work, due to all kinds of health and safety regulations.I have a couple myself, an LKB 2197 that goes all the way up to 2.5kV, and allows real time voltage/current adjustment, and a much newer VWR 300V which goes to... well, 300 volts...The VWR doesn't allow live adjustment, and also has a no-load shutoff that kicks in around 3V as it ramps the output up quite slowly.The LKB will ramp the voltage as fast as the current limit allows, and the only safety shutoffs are a 0.6mA earth leakage limit, and the sockets have optical sensors in them and wont turn on unless plugs are present.Useful for me for testing insulation, and leakage current on high voltage caps, and I paid less than £100 for both of them (separately, though from the same supplier by coincidence) including shipping.

author: thm_w
author_rank: Super Contributor
timestamp: April 01, 2020, 09:59:40 pm
content: Quote from: ArthurDent on April 01, 2020, 06:34:34 pmDid you check inside to see if the sudden load detection might be an analog circuit or is it all digital?All of the specs are stated as 1%, so theoretically 10V ripple at 1000V, but I'm guessing its better than that at low loads.https://www.marshallscientific.com/v//vspfiles/specs/PowerPac13_specs.pdf

author: CDaniel
author_rank: Frequent Contributor
timestamp: April 02, 2020, 07:19:40 pm
content: Actually +/-1%, I doubt in this case that it means 20Vpp noise . Usually the ripple is not defined in this way