Using Dick Smith Esr Capacitor Tester or Meter
to Check Ceramic and Non-Polarity Capacitors On Board
A Dick Smith ESR Meter
The dick smith esr capacitor
tester or meter besides can be used to check electrolytic
capacitor, it can also measure the non-polarity one such as the
Ceramic, Mylar, Film and so on. It is not mentioned in the meter’s
manual that it can test the non-polarity caps. In fact this esr
meter is specifically designed to check bad electrolytic capacitor
only.
When I began to do
some experiment with the Dick Smith esr capacitor tester i found
that it have the capabilities to check the non-polarity cap as
well. There’s only one disadvantage in testing the non-polar caps,
where it can’t test non polarity capacitor in the lower capacitance
value.
Any capacitance
value lower then .1 microfarad (104), the meter will not show esr
reading. This is due to that the dick smith esr meter can only read
esr values until 99 ohms. Perhaps others high end ESR meter such as
the B & K and Sencore lc103 capacitor tester have the special
range to test it. You will even be surprised too to discover that
the dick smith esr meter can test the non-polarity capacitor on
board (in-circuit without taking out the capacitor from the
board).
There was a Philips 17” Computer Monitor send for repair with
the complaint of top part of the display jump horizontally. You
could notice a bunch of horizontal black lines that appeared across
the top display. Since the fault was jumping horizontally, so the
caused of the problem would be in the vertical section.
The weird part was
that there were no components found faulty in this section. The
supply voltage, vertical output and oscillator ic and all
surrounding components checked to be okay. Even the vertical yoke
coil also in good condition. So where was the fault? For your
information I used digital capacitance meter to check the
non-polarity caps and esr meter to check the electrolytic
capacitors.
The display
jumping still looks very obvious and I’m almost giving up on this
repair because it took me lots of my time. Every track and every
component I have checked to be working fine and I’m still wondering
why I still could not locate the culprit in this little section of
vertical part.
I made my last attempt to tackle this problem by using the Dick
Smith ESR Meters. I compared all the non-polarity capacitor esr
value located surrounding the vertical output or driver ic. Finally
I found a capacitor with the esr value very high. The normal value
for a .22 microfarad non-polarity cap is between 6.5 to 7 esr ohm
but the defective one have a value of 14 ohms! It is almost double
in the esr value but the capacitance tested okay with a digital
capacitance meter.
Because of out of
normal esr ranges, the display jump. The good news is I discovered
the bad capacitor while checking it on board. If you are a
beginner, I strongly suggest that you remove one leg of the
capacitor and test it. Once you have mastered the art of using the
meter, you can begin to test non-polarity capacitor on board.
Changing the faulty cap with a new one solved the display jumping
problem.
Not long ago, a repair friend of
mine sends me an Oven circuit board. Upon checking the esr value of
the non-polarity capacitors, I found a capacitor esr value totally
out. The value has gone too high and caused the board to stop
working. The normal value of the capacitance is 824 (.82
microfarad) with a low 1.6 esr ohms, but the faulty one read 23
ohms esr value! Replacing the capacitor solved the
problem.
A good .82 microfarad ESR reading
A Bad ESR
Reading
If you really want to accurately
test a non-polarity capacitor, besides measuring the capacitance
value with a digital capacitance meter or using analogue multimeter
to measure the charge and discharge function, I recommend also that
you check it with a esr capacitor tester or meter as well. If you
missed one capacitor (which is suppose to be faulty and you think
it is good), the rest of your troubleshooting time is just a waste.
Hope this article will inspire you to get a esr capacitor tester or
meter to include to your range of troubleshooting tools. Happy
repairing!
Note:- Dick Smith ESR meter is no
longer available from the market because it has been replaced by
BLUE ESR
Meter.
Click here for more
information
|