Possible bad caps?

[skeeterbuck]

Do you think this is a possible bad cap?

I have 10 of them and they all read approximately the same.

P.S. is not the meter.

 

[TGP39]

If all ten caps are reading in this range, It’s not the caps. Do other electrolytic caps you have also read wrong? Make sure the black and red leads are fully pushed into the Mastech.

 

[skeeterbuck]

I tried several other electrolytic capacitors values (2.2uf, 33uf & 10uf) and they all read correctly.

The leads are in all the way. On this meter, if the leads aren’t connected, the lead inputs will light up.

 

[RetiredUnit1]

Wow, 71.7 nF....... that comes out to .0717 uF I'd say you have some counterfeit caps there....
Did you check the battery in the meter?
Is there a limit on the capacitance for the meter? Like maybe it topped out and is giving a bad reading?

 

[skeeterbuck]

I was thinking maybe a bad batch. I got them from stomp box parts and their Nichicon brand which is a quality part.

I stated in my earlier post that I tested some other uF rated caps and they all read within specs.

 

[RetiredUnit1]

I was thinking maybe a bad batch. I got them from stomp box parts and their Nichicon brand which is a quality part.

I stated in my earlier post that I tested some other uF rated caps and they all read within specs.

Yeah, I saw that. But most capacitance meters top out at like 2.2nf then 2.2uf then 220uf etc. I noticed this was *right at the limit* of some capacitance meters that I've used in the past.

Like I saw it was autorange, but maybe it doesn't have an 'out of range' error code....

 

[skeeterbuck]

RU1, you might be on to something there.

I don’t have any other caps with that high of a uF value to test against.

 

[Robert]

According to the manual that meters upper limit is 200uF and can take up to 30 seconds to make that measurement.

Hold the leads on there a bit and see if you get a higher measurement.

https://panda-bg.com/datasheet/646-340035-Multimeter-MS8268.pdf

 

[skeeterbuck]

Good catch RU1

I checked the online manual for my meter and the max uf range is 200.

Thanks to all for the help!

 

[skeeterbuck]

Just noticed your post Robert. FYI: I did leave the leads on for about a minute. It did finally go to “OL” which is an indication that the range had been exceeded.

 

[RetiredUnit1]

Good catch RU1

I checked the online manual for my meter and the max uf range is 200.

Thanks to all for the help!

I had to buy a better capacitance meter for the same reason!!!!

 

[RetiredUnit1]

I ended up getting a used dedicated capacitance meter that goes up to 2200 uf, like this one. Works very well!

Krista Capacitance Meter Model 30B-240 | eBay

Does not include battery or test leads.

www.ebay.com

 

[skeeterbuck]

As a follow up, a friend has a designated capacitance meter and I was able to use it to check the cap.

Results was 222 uF.

 

[mnemonic]

I always get real annoyed trying to test any electro larger than like 10uf with my multimeter, having to sit there and hold the leads while it thinks about it.

I got one of those mega328 tester kits off eBay for like £8 and I use that for electros now, way faster. Also it seems more accurate for picofarad caps too.

 

[RetiredUnit1]

Here's my old school capacitance tester. Uses a TUBE called a magic eye. I really bought this for the leakage to ground testing, you can pop an electrolytic in there at 600v and see if it has a ground leak. Most do leak at first, for a few seconds and then stop. Coupling caps can also be tested, their leakage doesn't change.

First video shows how to test for capacitance, second one shows how to test for leakage. This was a quite a few years ago before I retired....

 

[giovanni]

I love learning new stuff on this forum!