How do you test a capacitor?

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Just bought a generator and it failed within two hours of usage. Mfg. say
maybe capacitor and will ship a new one. But am not sure. I have a voltmeter
with capacitor readings. Know how to test for resistance and voltage but
never tried to test a capacitor. I know the circuit should be open, and this
one is open, but don't know if it is being charged nor how to do that
procedure.

Help!

Wayne



Re: How do you test a capacitor?




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Does the meter show any reading when you test the cap?





Re: How do you test a capacitor?



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say
I tested for continuity and it showed no short circuitry evident. I then
just connected the probes to both terminals and swithce the voltmeter from
high to low.... all indications fell to zero after only a short time...
which tells me that my VM may have charged, then masured as power
dissipated... but I'm just guessing.

I think I need to charge the cap with a battery and then measure... but
don't want to blow my VM... so... advice?

The readings on the cap is 24 microfarads plus minus 5% 400 VAC 50/60 Hz

Wayne

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Re: How do you test a capacitor?




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I would put the meter on ohms and connect it to the cap. Then switch the
leads over where they are connected and see what happens. If the cap is OK
the meter will deflect up and then go down. When reversed the meter will go
below zero come up and go down. This indicates possibly a good cap.

Is this a gas power generator? How did it fail - symptoms?




Re: How do you test a capacitor?



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from
go
OK, I'll try that. This is a brand new 13HP four stroke driving a 5,500 Watt
generator. It started with a single pull and reved up showing full power and
my son started welding. It worked for a couple of hours then simply stopped
producing juice. Motor running fine, no other indication except no output.

He took it back to Pep Boys who refused to exchange it ( after one day!) and
is now saddled with the problem of facing one month service waiting time...
so much for other than Wal-Mart vendors! ( I bought a HDTV from Wal-Mart, it
did not live up to the advertised standards, and they simply gave me a new
one... I think I'm spoiled by their kind of service.)

So son is running around getting replacement capacitors and fuses even
though they may not be needed. And can't get a straight answer from Pep Boys
or the Power Pro 5500 people.
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Re: How do you test a capacitor?




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No fuses or circuit breakers?

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Yes, Costco or Wal-Mart are clearly better than Crap-Boys.

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Did it come with a wiring diagram?




Re: How do you test a capacitor?


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  Simplest things first - did you attempt to reset
the circuit breakers? (Sometimes overlooked because
it can be hard to see they're tripped.)

Ed

Re: How do you test a capacitor?



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then
OK
Watt
and
stopped
output.
and
time...
Wal-Mart, it
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new
Boys

We removed the fuse and tested and is ok. Circuit breaker also.

During the last pull he got a trickle of juice, but then quit producing
anything.

Don't know if he has a circuit diagram. he's out looking for help now.



Re: How do you test a capacitor?




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OK. I just wouldn't suspect a capacitor right off unless it's a known
problem. Can't he just return it for his money back?







Re: How do you test a capacitor?



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He tried to return it in exchange of a working unit. He was told he had to
take it to the factory authorized facility. Two week delay in just getting
an appointment.

Have written to the retailer's HQ and they are asking for more info. So...
I'm hoping for a quick solution but who knows?


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What a scum sucking company.




Re: How do you test a capacitor?



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It may be worthwhile to contact the local Better Business Bureau and
Consumer Protection Agency. Also, see if a local TV station would like to
make this one of their little investigative reporting segments (especially
if they do not have Poop Boys as a sponsor). Maybe talk to a local
competitor and give them a write-up of your problems with an assurance that
they would not treat their customers so callously. Make a big sign for your
car saying "Pep Boys Sucks", with an explanation that people can read.
Write an editorial for the local paper. Make sure Poop Boys gets enough
negative publicity to make them realize they will only lose business by
acting this way. They have now lost mine.

Paul



Re: How do you test a capacitor?


On Wed, 07 Feb 2007 19:23:41 GMT, "Homer J Simpson"

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---
Read the thread, moron.


--
JF

Re: How do you test a capacitor?



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One way to test it is to charge it up to 100 VDC (carefully), and then
discharge it through a 100K resistor. The time constant should be 24 x 0.1
= 2.4 seconds to reach 37 VDC. An even more thorough test would require
charging it to 600 VDC and making sure it is not breaking down or leaking.
Such testing can be dangerous or even lethal, but will be more conclusive
than a simple ohmmeter check.

Paul



Re: How do you test a capacitor?



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Thanks!



Re: How do you test a capacitor?


On Tue, 06 Feb 2007 19:56:32 GMT, "Wayne Lundberg"

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If you have a capacitance range on your meter then simply connect the
probes across the capacitor terminals (make sure all other leads are
disconnected from the cap). Since you know the cap should be 24uF then
.look to see if the meter reads very close to this value (22.8uF -
25.2uF). This is not necessarily an indication that the cap is "good"
- you need other test equipment to determine this, it is a indicator
that it may not be faulty. The cap can measure the right value on your
meter but it may break down when subjected to the much higher voltage
it sees in normal operation. For the general public who can't carry
out full testing the best option is to try a new cap and if the fault
is still evident then the likelihood that your original cap is faulty
is nil. Once this is established then return your generator for a new
one.

The only problem with the self fix route on brand new products is that
the supplier/distributor may void the warranty because you have
"played around with it" when you are not an authorised repairer. It is
generally safer to simply not do anything and take it back and say
"fix it or replace it " under warranty.

Re: How do you test a capacitor?



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voltmeter
this

My son took it back and asked the manager to replace it or fix it. They
refused, saying the unit had to go to the manufacturer's repair shop, which
he did and was told two week minimum. I'm suggesting he get his credit card
company to help him get a refund and return the unit.

I've never heard of such terrible service as buying a new machine and the
vendor not exchanging it if it does not work after one day and only a few
hours of use. Don't know how Pep Boys stay in business!

Wayne



Re: How do you test a capacitor?


On Wed, 07 Feb 2007 16:56:16 GMT, "Wayne Lundberg"

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That is really surprising, the bad treatment at Pep Boys. It makes bad
business sense too. I wonder if it's a local management problem
because I've never had a problem returning something to Pep Boys. The
credit card company may work out really well. Twice I've had a
complaint with a business and notified the CC company. Both times the
CC company was very helpful and I didn't lose any money.
ERS

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Speaking of Pep Boys, had car in shop for heater core replacement,
quoted over the phone $630 to repair and upon picking up the bill
was $890.00 and I refused to pay, after about an hour of them trying
to get me to pay they gave it to me for $630 their quoted price!
Take the thing back and leave it there and call the credit card
company and have them reverse the charges!


Re: How do you test a capacitor?



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I don't know where this is, but I would double check it with state law. Even
if the credit card company will reverse the charges, it could still leave
someone responsable by law, and perhaps the defendant in a small claims
action that you would probably loose. It happend to me.

It doesn't seem right, because we have all gotten real cozy with most no
fault return policys, but it is not required by law. Just make sure to
review the return policy EVERYWHERE you shop. After getting bit on this one
time myself, I did, and it sure changed my buying habits.



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