What is the easiest way to test a capacitor

[zorgan]

Are there any dedicated/specialised meters which can test capacitors on the market?

 

[Taylortwocities]

Try looking HERE

 

[zorgan]

Try looking HERE

smart arse

no I'm wanting to see if anyone on here has experience using certain testers, tell me their experience with them!! lol

 

[Taylortwocities]

Oh, you'll be wanting someone who knows about electronics then?

That's different. Byeeee.

 

[bernardgreen]

Testing capacitors is not straight forward and a single piece of test equipment that will perform all tests any capacitor is not going to exist. ( or if it does it will be very large and very expensive.

Capacitor vary in value ( capacity ) from several Farads down to 1 or 2 pico Farads

1 Farad = 1,000,000 micro Farads

1 micro Farad = 1,000,000 pico Farads

That alone makes a universal meter difficult.

Capacitors leak as the insulation between the plates is not perfect, this leakage is an important parameter. In small ceramic capacitors the leakage is very small, almost zero ands is measured by measuring the resistance of the capacity at DC which will be in many hundreds of Mega Ohms, but in larger electrolytic capacitors it can be significant and is often measured by charging the capacitor to a voltage and then recording the rate at which the voltage drops as charge is lost by leakage.

 

[TicklyT]

One check we used to use was to connect to an analogue resistance meter. The meter needle would kick, then drop towards infinity as the meter battery charged the capacitor through the internal resistance of the meter. The larger the capacitor, the longer it takes for the current to drop.

Of course, a large capacitor already charged could wrap the meter needle around it's end stop...

 

[chivers67]

One check we used to use was to connect to an analogue resistance meter. The meter needle would kick, then drop towards infinity as the meter battery charged the capacitor through the internal resistance of the meter. The larger the capacitor, the longer it takes for the current to drop.

Of course, a large capacitor already charged could wrap the meter needle around it's end stop...

Old BT Test Desk? That's how i used to test to see if a telephone was connected to a subs line.

 

[timbim]

As Bernard says, no single, cheap device can handle the full range of caps available. For smaller caps, most decent multimeters will have a capacitance test function, sometimes called LCR mode (inductance, capacitance, resistance). You should be able to pick up such an instrument for under £50.

 

[ban-all-sheds]

smart a**e

The key word there being "smart".

As in not dumb.

no I'm wanting to see if anyone on here has experience using certain testers, tell me their experience with them!! lol

Are there any dedicated/specialised meters which can test capacitors on the market?

which is not the same thing at all, is it?

 

[Taylortwocities]

Thanks BAS

I must have been confused by the title of the topic.

"What is the easiest way to test a capacitor"

Silly old me.......

 

[plugwash]

Are there any dedicated/specialised meters which can test capacitors on the market?

There are a wide variety of meters on the market that can be used to test capacitors but to get an idea what equipment would be suitable for you we need to know.

1: what sort (types and range of values) of capacitors are to be tested?
2: what do you want to test them for?

 

[zorgan]

First of all thanks to the people who have replied on topic and most helpful posts, you guys know your stuff thanks I will research into those different methods for testing capacitors more.

ban-all-sheds why don't you make a constructive post "on topic" here (mainly the topic of capacitors and your advice on testing them) instead of analysing the "way" I have asked my question and we might get somewhere here.

the first question is "what is the easiest way to test a capacitor?" on the topic title then the second question within the body of the first post --> "Are there any dedicated/specialised meters which can test capacitors on the market?"

the answer could be "Google it to find out", this is an electronics forum and this question is about electronics which is "on topic" furthermore I want to interact via the question which is why people post on a forum in the first place. I'm sorry I wasn't clear or specific enough for some people on the forum but it seems some people have actually replied constructively.

so what is your view on this subject ban-all-sheds ? have you tested some capacitors in the past, if so which method did you use to test them?

 

[stillp]

this is an electronics forum

Umm... NO! The forum title is "Electrics UK"

More constructively, what type and value of capacitors did you want to test, and what parameters do you want to test them for?

Usually in electronic servicing, small capacitors are tested by replacement. That would not often be economic for power factor correction capacitors.

 

[zorgan]

I stand corrected sorry it's "Electrics UK" lol

components where these --> 470 microfarad 24v capacitors, I replaced them yesterday on a power supply, the repair went fine however I had a power supply I was looking at the day before which had a lot of different caps on it, none visually bulging but could however had been faulty, I usually always swap test but there were quite a few on this board so decided to leave it out as it was a time factor at the time.

 

[plugwash]

Something like the atlas LCR would probablly be a good choice for testing such capacitors.

However you can't reliablly test components while in-circuit as other parts of the circuit can give false readings and in some cases could even be damaged (though this is unusual as meters tend to give false readings) so you would have to remove them for testing and by the time you've gone to the effort of removing electrolytic capacitors you may as well just replace them all. If some of them have failed it's likely others are on the way out too.