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Ric
29th June 2006, 01:40 PM
hey there

Capacitors can be flakey little devices and whilst cheap, the cost of replacing rather than testing adds up over time.

Has anyone got or used or tried a DMM capacitance tester such as

http://www.jaycar.com.au/productView.asp?ID=QM1572&CATID=12&keywords=&SPECIAL=&form=CAT&ProdCodeOnly=&Keyword1=&Keyword2=&pageNumber=&priceMin=&priceMax=&SUBCATID=444

looks like a neat little device - goes up to the big 20 000uf caps used on pinball boards too

interesting to hear comments?

Ric

MadMikeAU
29th June 2006, 03:00 PM
Quite a volume discount on 6 !!!
I mean, if we want enough, one person goes and gets and even with postage @ 3.20 a piece. We are still in front.

Having said that, the major cost of replacing caps is the time it takes for potentially no gain. This would be a huge time saver, in that regard. hmmm....

Ric
29th June 2006, 03:14 PM
i think it looks like a nifty tool

and the costs of caps does add up

I just had to replace at least 15 on a board - yes they were smashed but to tes others would be a great help

Prof
29th June 2006, 04:22 PM
I would think you would have to lift at least one leg to take it out of the circuit to test accurately.

Johns-Arcade
29th June 2006, 04:42 PM
Better to use an ESR meter for in circuit caps

Regards,

JWG.

Mrvfone
29th June 2006, 04:53 PM
Well with the age of most of these devices and the fact that at least one leg needs to be lifted from the PCB, (Which is quite hard with some caps) Would it not be a good idea to just replace them anyway? ;)

Not having a go at anyone.. just my 2c.

I know i re-cap all my chassis once they work. I wouldn`t have thought the cost would have been too much over $20. But i do buy in bulk and wholesale... So that would help keep costs down. Most expencive caps are the high voltage ones. Like 200V 680 uF.. I`m sure i saw a place selling them for $7 each.. Also i don`t think Jaycar or tricky Dicky sell them...

The bigest pain with caps is the need to have a "collection" of them if you want to have most on hand ready for action... :D

I haven`t used the meter from Jaycar.. But have used a more expencive meter. But only to check SMD caps cos most don`t have there size on them (Well for 0402 Packages anyway ;).

Mrv.

Ric
5th July 2006, 09:08 AM
sorry for the newbie questions however what would be difference between the ESR meter and the Capacitance DMM

I assume the ESR is giving you an OHMs reading for the series reisstance across the cap and the cap DMM is actually testing the vlaue of the cap

although the ESR can test caps in circuit (from what i have read), doesn't a reading of the caps value give more valuable data?

Ric