Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

[mmartell]

This has happened several times now on different sets so now I'm positive there is something wrong with this thing. Reads Va Vs Vzbias etc fine.

It is some Korean unit I've had forever - was given to me by an electrician who may have had a few "oops" with it back in the day. For all I know it was snuck over the border from North Korea before getting here on the slo boat.

Does this have anything to do with floating ground nature of these voltages ?

[retiredcaps]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

Let's see a picture of your meter. A picture of the insides (pcb), both sides, would also help.

It would also help to describe where you are putting the black probe (ground) when measuring. Some people don't realize there are two grounds (hot and cold). Or they don't know where hot and cold ground are.

[mmartell]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

It reads voltages with respect to cold and hot ground fine. I'm talking about Vsc and -Vy which have a pair of test points on the ysus board.

I can't post pics atm will try to find an online pic.

[retiredcaps]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

Okay, I think I understand now. Something like this diagram?

So if your multimeter can read positive and negative readings fine with with respect to ground, what is it showing when you try to read Vsc + and - test points?

[mmartell]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

Yes exactly like that. One reads a lower, fluctuating voltage. The other reads nothing until I flip the scale up to 1k (from 200v) then reads about 1700 ! Can't remember which is which and these readings were from working sets.

[tom66]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

Yes, if you Meyer has inadequate shielding you will find it hard to measure things on a plasma, especially the floating ground parts. What meter do you have?

[mmartell]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

It's an RCC510, at least that's what it says on the front. Not at home and there was little on the www last time I looked.

[mmartell]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

This probably doesn't help but here's an image I found.

http://thumbs2.picclick.com/d/l400/p...ith-probes.jpg

[tom66]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

You should consider investing in a better meter. I'm sure retiredcaps will have something to add but the Fluke 17B is worth a look.

[mmartell]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

Haha ok thanks tom. Btw what type of radiation is interfering with the function of the meter ?

[tom66]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

Electromagnetic radiation...Interference from the plasma panel and sustain boards. Just bring an AM radio near a plasma set with the cover off... it will overpower most stations.

[retiredcaps]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

It is some Korean unit I've had forever

The original design manufacturer is a Fine Instruments 201.

http://www.finest.co.kr/html/pro_10.html

Fine also makes some DMMs rebadged under UEI and Klein.

[retiredcaps]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

You should consider investing in a better meter. I'm sure retiredcaps will have something to add but the Fluke 17B is worth a look.

The newer 17B+ is out now for the same price as the 17B. It has a bit more functionality and larger LCD display digits.

A fellow Canadian now living in New York just posted a video review/teardown.

http://www.youtube.com/watch?v=OCbAWbqiygg

Note: I don't have this meter so I can't give first hand comments about it.

PS. A budget would help narrow down the selection criteria.

[mmartell]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

There it is ! Thing of beauty, isn't it ? Lol.

So would a few well-placed pieces of conspiracy foil allow me to take some measurements until I can go through the process of procuring a replacement ?

[mmartell]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

PS. A budget would help narrow down the selection criteria.

Well quite honestly we're not building Space Shuttles here but I would say under $100 would be about right.

I would like a large lcd screen, continuity beep and auto-ranging is nice as well. Are any of the ones with thermocouples reliable ?

[tom66]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

The foil would only work if it was inside the meter and connected to the common terminal. However this would compromise the safety of the meter if it was not designed in in the first place (flashover distances, etc.)

[retiredcaps]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

For $100, you certainly have a number of choices.

1) I know tom66 has the BK2709b and he is happy with it. It is the winner of the $100 eevblog shootout.

http://www.eevblog.com/2010/07/11/ee...i-t-part-1of2/

2) For $50 CDN, you can get a basic new Fluke 101. It is their lowest cost meter and for the purposes of badcaps repairs, it will meet most of the needs especially if there is another meter to measure current which is rarely required.

I talk about here.

https://www.badcaps.net/forum/showthread.php?t=42109

As I mentioned, the Fluke 107 in Martin's review is identical to the 101 but without all the extra functionality found in the 107.

3) If you are not opposed to buying used, you can get a number of good second hand Fluke meters in the $100 range either locally on kijiji or with patience on ebay.

You want to put these Fluke models on your radar: 115, 117, 77IV 175, 177, 179, 83 III, 85 III, 87 III, 83V, 87V, 187 and 189. All have largeish lcd digits and fast continuity speed. Yes, I have used or own the above listed.

For the 115 and 117, try not to pay more than $70 CDN.

4) BTW, I know some people will comment that brand xyz offers more bang for the buck. While that may be true, probing around plasmas with 200V+ voltages, the safety of the multimeter should be primary concen. If there is PFC circuitry involved, voltages approaching 400V are common on the SMPS hot side.

You will, like I, have an oops moment, and you want both yourself and the multimeter to survive.

Trying to measure the nearly 400 DCV large filter capacitor, but your multimeter is set to measure resistance. Oops.
Trying to measure the ACV of the inverter transformer going to the ccfls on a LCD which is possibly more than 1500V during initial power up. Oops.
Trying to measure the power mosfet on the hot side to see if it is shorted, but forgot power was on? Oops.
Trying to measure voltage, but your probes are in the amps jack. Oops.

5) For non Fluke alternatives, I own a Greenlee DM-200A (made by Brymen). It has nice big lcd digits, fast continuity, proper input protection and is UL listed. I got mine used for $21 USD total (a great deal). I really like the large digits and compact size. You can see a picture here

https://greenlee-media.precis5.com/0...18865aa693cc24

If I could get more for $21 USD, I would buy them.

6) For those wanting to know more about input protection, Dave does a good tutorial using the Fluke 27. Most people, incorrectly, just think that the fuses protect the multimeter.

Note the Fluke 27 doesn't have a very large lcd display and very slow continuity speed. However, if you can get one for $40 or less, it is built to last.

http://www.eevblog.com/2012/10/19/ee...tion-tutorial/

http://www.eevblog.com/2012/10/26/ee...iode-followup/

7) Anyway, I gave you enough to think about and to keep you busy for a couple of hours. You can ask more questions once you narrow down your choices a bit.

[retiredcaps]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

Are any of the ones with thermocouples reliable ?

I had a few occasions where I have used them and they work. I'm not sure how accurate they really are, but I'm happy with the ballpark reading for my purposes.

I also picked up an used Fluke 62 for $20 CDN locally. The deals are out there. You just need to know what is below market value and have patience.

[mmartell]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

That IS alot of options. Will look into them. Thanks.

[retiredcaps]

Re: Is There Some Earthly Reason my Meter Can't Read Vsc and -Vy ???

The foil would only work if it was inside the meter and connected to the common terminal. However this would compromise the safety of the meter if it was not designed in in the first place (flashover distances, etc.)

I agree with Tom to NOT modify the multimeter.

One thing that might help/work is to get a set of really long test probes so you can place the multimeter farther away from the TV. However, this might be a two person job unless your eyesight is really good.