Dan,
Thanks for your comments. In principle, I agree with you regarding the
effect of capacitor size and the usefulness of this test, and you
certainly could not use it successfully for small disc or tubular
capacitors. However, the capacitor used in my TR3 certainly does
respond as noted. My analog meter is a "cheapie No-Name" and it's
highest resistance range is only 20 Meg-ohms, but it does the job. Try
it for yourself.
BTW, that was a nice article on the "Electrical Loads, parts one and
two"
Russ
TS43694LO
DANMAS@aol.com wrote:
>
> In a message dated 1/6/99 10:42:23 PM Eastern Standard Time, ruset@flash.net
> writes:
>
> > a condenser can also be checked if you
> > have an analog volt/ohm meter. (you know, one with a meter that has a
> > needle). A condenser can either open circuit or short. By using the
> > ohmmeter and the highest range, when you put the leads on the condenser,
> > if it is shorted, the needle will read "0" ohms. If open, it will read
> > the maximum resistance, or infinity (assuming you don't "short" the
> > probe tips with your fingers). If the condenser is ok, you should
> > notice the needle "kick" up scale a certain amount, and then drift back
> > to infinity as the condenser charges. You can verify it's integrity by
> > reversing the leads to the condenser and recharging it to the opposite
> > polarity. Since the condenser has a charge now, the needle will
> > generally "kick" higher than it did the first time. Of course, this
> > test will not tell you the condenser's integrity when it is at engine
> > operating temperature......
>
> Russ,
>
> This method of testing will work if the capacitor (condenser) is large enough,
> but those used in our ignition systems are not. The time constant for these
> small units is so short that the needle won't have time to deflect before the
> capacitor is charged/discharged. This works quite well for power supply filter
> capacitors - in fact, on some of those, you can connect the meter, go get
> lunch, come back, and the meter will still have a reading.
>
> Dan Masters,
> Alcoa, TN
>
> '71 TR6---------3000mile/year driver, fully restored
> '71 TR6---------undergoing full restoration and Ford 5.0 V8 insertion - see:
> http://www.sky.net/~boballen/mg/Masters/index.html
> '74 MGBGT---3000mile/year driver, original condition - slated for a V8 soon
> '68 MGBGT---organ donor for the '74
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