scott2000



mjrippe

Re: Invention Release! Carlson LV Capacitor Leakage Tester
« Reply #1 on: May 11, 2018, 12:29:21 PM »
Watched it last week.  His Valium voice annoys me, but I made it through.   Sadly he only compares it to two vacuum tube era testers.  If he showed it was better than my Sencore LC75, for example, I would be tempted to build one. 

scott2000

Re: Invention Release! Carlson LV Capacitor Leakage Tester
« Reply #2 on: May 11, 2018, 12:45:40 PM »

I think your information is very useful for me.


lol

Yeah the build is smd anyway....I can't imagine putting it on a board would be recommended or reliable??? Guess I'll keep researching..... always wanted a leakage tester....

fazer

Re: Invention Release! Carlson LV Capacitor Leakage Tester
« Reply #3 on: May 12, 2018, 10:45:00 AM »
I use an old cap checker with a magic eye dispalay so can check up to 500 volts. 

I have a article for building one from a past audio amateurs mag.  If I find it I’ll post it.

scott2000

Re: Invention Release! Carlson LV Capacitor Leakage Tester
« Reply #4 on: May 12, 2018, 11:21:29 AM »
I use an old cap checker with a magic eye dispalay so can check up to 500 volts. 

I have a article for building one from a past audio amateurs mag.  If I find it I’ll post it.

That would be Great!

mjrippe

Re: Invention Release! Carlson LV Capacitor Leakage Tester
« Reply #5 on: May 12, 2018, 01:52:51 PM »
I use an old cap checker with a magic eye dispalay so can check up to 500 volts. 

I have a article for building one from a past audio amateurs mag.  If I find it I’ll post it.

The video makes a point about how his low voltage tester catches bad caps that the HV ones don't.  However he also describes how he set the leakage test point at only a few uA.  My Sencore has voltages up to 500, but includes charts of "acceptable" leakage amount for various cap values.  So in theory, his tester is only appropriate for a certain range of cap values.  There are a lot of factors to consider and any tester is only capable of checking a few of them at best.

scott2000

Re: Invention Release! Carlson LV Capacitor Leakage Tester
« Reply #6 on: May 12, 2018, 02:30:45 PM »
I may sound stupid asking as I don't know if I've had issues with any new or even  NOS caps from surplus afaik but, would a leakage tester for high voltage caps be a good investment to consider??? They're pretty steep but, seems like it's an important item?????

scott2000

Re: Invention Release! Carlson LV Capacitor Leakage Tester
« Reply #7 on: June 27, 2018, 08:50:47 PM »
Any opinions on the Eico 950B???? I just want a good leakage tester..... And want to get one as cheap as possible and restore it if needed....

rackmonkey

Re: Invention Release! Carlson LV Capacitor Leakage Tester
« Reply #8 on: July 01, 2018, 04:19:35 PM »
I saw this when he posted the first video.  Interesting. I’m about to start building one to play with. I have a Heathkit IT-28 that I restored a while back that I currently use. I intend to compare results with that. Will report back what I find.

Also, wouldn’t this post be more appropriate for the Chamber than the Brewery?

BT
Whether you think you can or you think you can't, you're probably right.

scott2000

Re: Invention Release! Carlson LV Capacitor Leakage Tester
« Reply #9 on: July 01, 2018, 04:39:28 PM »
I saw this when he posted the first video.  Interesting. I’m about to start building one to play with. I have a Heathkit IT-28 that I restored a while back that I currently use. I intend to compare results with that. Will report back what I find.

Also, wouldn’t this post be more appropriate for the Chamber than the Brewery?

BT

Very cool....I'm not comfortable with surface mount yet or else I'd try.....I'm guessing it maybe wouldn't be the same specs if it were done  a different way????


rackmonkey

Re: Invention Release! Carlson LV Capacitor Leakage Tester
« Reply #10 on: July 01, 2018, 07:33:28 PM »
I plan to do it with through hole components. He built the prototype on perfboard for the first version of the device.
Whether you think you can or you think you can't, you're probably right.

scott2000

Re: Invention Release! Carlson LV Capacitor Leakage Tester
« Reply #11 on: July 02, 2018, 01:14:14 PM »
I plan to do it with through hole components. He built the prototype on perfboard for the first version of the device.

Ok!  I think I'll wait to hear some comparisons. I have no way of knowing/comparing how well it may work.....


but probably will get the bom.......is the mmbt3906 the same as the 2n???? I guess I need to research the surface mount to TH deal....


Please keep us updated....!!
« Last Edit: July 02, 2018, 07:10:53 PM by scott2000 »

Gold

Re: Invention Release! Carlson LV Capacitor Leakage Tester
« Reply #12 on: July 05, 2018, 01:06:08 PM »
I don't have to do DC leakage tests very often. The only time I test for DC leakage is for large  computer type caps that would be hard and expensive to replace. Often they have odd mounting methods. For everything else it's easier to just replace them.

I was thinking a variac into a step up transformer followed by a bridge rectifier would do for occasional use. Anything wrong with that plan?

Re: Invention Release! Carlson LV Capacitor Leakage Tester
« Reply #13 on: July 06, 2018, 09:24:46 PM »
I have a Solar capacitor tester, it needs new caps but overall its ok. It doesnt have a magic eye, instead it has a standard analog meter to display leakage in mA , the magic eye is more intuitive but it only tells you if its good or bad, the analog meter tells you how much leakage current is actually flowing. I also have ESR testers.

In my opinion ESR testers are much more useful than leakage testers specially when troubleshooting a SMPS or similar, leakage testers such as the EICO, Heithkit and such are pretty much boutique accesories to fool around with old caps. If you think about it, they are only there to confirm that a capacitor is bad after you replaced the capacitor, and if you already replaced the capacitor, who cares if the original was leaky or not? it can of course confirm that the failure in your equipment was due to a leaky cap I'll grant you that, but then again, if you are restoring an old radio or similar, you just replace those paper capacitors and electrolytics no questions asked and you dont need a capacitor leakage tester to do that. An exception is what Gold mentions, when you cant replace the caps because they are either very exotic or expensive.

I always though that those old capacitor testers are a one trick pony, the only useful feature is the leakage test, the rest is completely obsolete and can be done with a simple DMM. In my opinion, its better to own something like an insulation tester that can measure voltages as low as 50V and as high as 1000V, you can use them to test old capacitors but you can also use the meter for what its meant to be used, so you have a more versatile instrument. Even better, to measure leakage you can use a high voltage PSU, and use something like a 6 1/2 digit multimeter as a current meter in series with the cap or the EEVBlog microcurrent, much more precise than any cap tester I know.
« Last Edit: July 06, 2018, 09:45:43 PM by Dualflip »

scott2000

Re: Invention Release! Carlson LV Capacitor Leakage Tester
« Reply #14 on: July 06, 2018, 10:15:43 PM »
I'm just interested in mostly the polys and micas in a bunch of the tube stuff.... I always replace electros and wax, etc but some of these polys and oil caps can still be good and , I hate to throw them out.....

I had an old Hammond that I couldn't get rid of some hum and weird stuff.... All the polys and oil cans used for coupling and some smoothing tested fine but, I replaced them anyway because I was at the end of my rope..... Fixed the problem.....

I still saved the caps for when I can test them beyond capacitance and a cheap esr but, my guess is they are leaky.......

What are these other tests you mention???Any links???? I've kinda heard about using a megger before but never dove into it......... the eevblog ...current.....??? Sounds interesting.....


Re: Invention Release! Carlson LV Capacitor Leakage Tester
« Reply #15 on: July 06, 2018, 10:45:24 PM »


What are these other tests you mention???Any links???? I've kinda heard about using a megger before but never dove into it......... the eevblog ...current.....??? Sounds interesting.....

A standard multimeter in ohms range is not suitable to measure capacitors because it produces a very small voltage, a megger is simply a high voltage ohm meter, so say you have a poly or mica cap rated at 100V , you set your megger at 100 volt and you should see (ideally) an infinite or very high resistance, a megger is primarily used to test insulation, but you can test capacitors aswell. The advantage of a megger is that you can also test high voltage capacitors like those 1KV ceramics, most capacitor meters I've seen wont go beyond 600V.

The other set up I was talking about is using a high voltage PSU and a very sensitive current meter in series with a capacitor, the EEVBlog microcurrent is something you use in conjunction with your DMM to measure very low currents, but it is not absolutely necessary, a simple DMM in current mode should suffice to measure capacitor leakage current. Here is a youtube vid using this setup https://www.youtube.com/watch?v=ASqMIFotKVo

I've also used that setup with lower voltage electrolytics using a standard PSU and a DMM, it works great.
« Last Edit: July 06, 2018, 10:51:04 PM by Dualflip »

scott2000

Re: Invention Release! Carlson LV Capacitor Leakage Tester
« Reply #16 on: July 06, 2018, 11:47:35 PM »
Ok cool!! Yeah I like this guy.Has tons of good info on his channel

Love his plate current video using transformers....Such an old method but I never knew about it before....

Thanks!! I'll check these things out...

Re: Invention Release! Carlson LV Capacitor Leakage Tester
« Reply #17 on: July 07, 2018, 12:47:10 AM »
Ok cool!! Yeah I like this guy.Has tons of good info on his channel

Love his plate current video using transformers....Such an old method but I never knew about it before....

Thanks!! I'll check these things out...

If you are on a budget, you can get an insulation tester for <100 USD, check e-bay

Whoops

Re: Invention Release! Carlson LV Capacitor Leakage Tester
« Reply #18 on: August 22, 2018, 04:08:09 AM »
I like Carlson Lab videos, great info

Cool Dude


 

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