EDS CapAnalyzer 88A Series II Assembly instructions

EDS-88A
CapAnalyzer Series II
In-Circuit Electrolytic Capacitor DCR/ESR Tester
OPERATING INSTRUCTIONS
and
OWNER’S MANUAL
©EDS-Inc 1997-2018
For Technical Assistance
parts or FAQs go to
www.eds-inc.com

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TROUBLESHOOTING CAPACITOR-
RELATED PROBLEMS
using the CapAnalyzer 88A
ATTENTION: THIS UNIT IS DESIGNED TO CHECK ELECTROLYTIC
CAPACITORS IN OR OUT OF CIRCUIT WITH POWER DISCONNECTED FROM
THE CIRCUIT UNDER TEST. IF THE UNIT UNDER TEST IS POWERED UP,
THE POWER WILL BACKFEED INTO YOUR CAPANALYZER AND DAMAGE
BOTH UNITS!
DO NOT ATTEMPT TO BEND THE TWEEZER PROBE ENDS, THEY ARE
HARDENED BERYLLIUM COPPER AND WILL SNAP OFF.
Troubleshooting and locating defective electrolytic capacitors has been a thorn in the
side of all technicians for many years. The CapAnalyzer 88A will help solve problems
caused by electrolytics in audio, video, power supply, and system control circuits. This
manual will also show how to locate these bad capacitors easily without having to unsolder
and test, or cut up the pc board, and without needing the service manual, by using
specialized test equipment specifically designed to make you more productive. Although
you will have to unlearn your old-fashioned, slower methods, those who will be progressive
enough to learn these tricks will have much more time on their hands to spend with their
family and friends.
There are several ways a capacitor can fail. High temperatures usually cause electrolytics to
dry up. In high-frequency circuits such as digital pulse-width power supplies, the capacitors
tend to leak. In low-voltage circuits such as system control and low-voltage supplies,
capacitors tend to short, partially or completely. Therefore, the technician must first check
all electrolytics for DCR (DC Resistance) shorts or leakage, then check for physically leaky
or dried-up capacitors by measuring high-frequency ESR (Equivalent Series Resistance).
These methods will not require a soldering iron, a service manual, or any cutting tools. It
will require some logical reasoning, good eyesight, and some specialized equipment; your
$29 DVM won't help you find the tough dogs. With the CapAnalyzer 88A (and the
LeakSeeker 82B or LeakSeeker 89), hours can turn into minutes, and repairs that were once
considered "no-fixers" can now be profitable.
DRIED UP and PHYSICALLY LEAKY CAPACITORS
As a capacitor dries up internally, it can become electrically leaky. As the cap dries up, it
can cause strange problems in the particular circuit it is in. For example, in the TV's vertical
section, it can cause vertical overlap, insufficient vertical, too much overscan, or non-linear
scanning. If the cap is in the power supply, jail bars or "hairy" interference may ride on the

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video and power semiconductors can keep failing. In the audio section it can cause
distortion, feedback or low audio. In the system control supply it can cause intermittent
functions and microcontroller confusion, shutdown, even a blank display. In the video
circuits it can cause incorrect colors, distortion, even a fully scrambled picture.
Usually, the problem will be less noticeable if the unit is left on for some time. That's
because a dried-up capacitor will usually decrease its ESR with higher temperature.
Other consumer electronic components can also have these problems, but with a different
culprit: surface mounted capacitors. Most camcorders, VCRs, and big screen TVs now use
surface mounted electrolytic capacitors in modules. In VCRs, they are usually in the sound
MPX decoder module. In big screen TVs, they can be in the sound module and in the video
PIP and video convergence circuits as well. In camcorders they are everywhere, usually
showing up as varying speeds if they are in the servo circuits, color or sync problems if in
the video, and low, distorted, or missing audio if in the audio circuits.
Most technicians already know these symptoms, and have an idea where on the board to
start. The first step is visual observation; vacuum all debris off of the board and look for
dark areas under each cap, for bulging tops, and for splitting vinyl covers. On surface mount
caps, look for the solder connections under the cap to have a cloudy look. After replacing
the obviously defective caps, it is important to clean the board with a stripper solvent and to
check all local feedthroughs, as these type of capacitors leak an acidic electrolyte that loves
copper!
After visual observation and replacement of the obvious offenders, it will be necessary to
measure the rest of the caps. The problem of measuring each capacitor is more difficult than
measuring resistors, which can be measured in circuit quite easily with any cheap DVM.
That is because any circuit that encompasses an electrolytic already has some DC resistance
and some capacitance from other parts of the circuit. Some "capacitor checkers" claim to
work in circuit, but since they actually measure circuit capacitance and resistance, they give
such erroneous readings that caps usually have to be unsoldered and re-measured out of
circuit anyway. In fact, even some of the most expensive capacitor meters (over $2000) will
not always measure capacitors accurately in circuit. Some meters measure the capacitance at
two different frequencies, and show it as two different readings. Most ESR meters will show
a partially or fully shorted cap as "perfect".
Speaking of "ESR" meters, their designers already know that the trick to locating bad
capacitors in circuit is not to measure capacity at all! Years of testing by many technicians
and engineers has shown that as a capacitor ages, its Equivalent Series Resistance increases.
What is ESR? Without going through the math, a perfect capacitance will measure as an

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open circuit at DC, and will show less and less resistance as the frequency across it
increases. Some inexpensive cap meters utilize this fact by measuring a cap's impedance at a
fixed frequency such as 1KHz and translating the reading to capacity. In reality, checking a
cap at 1KHz only works if the cap is being used in a circuit that also utilizes 1KHz.
Television and VGA monitor video circuits use frequencies into the megahertz, and in
PWM power supplies, frequencies of 100KHz and higher are commonly used. It makes
more sense to forget about capacitance altogether and use our knowledge that high
frequency ESR increases with age and as a cap dries up.
Several ESR cap checkers have appeared throughout the years. The originator was a simple
meter that used 50KHz and a simple mechanical meter. A more recent meter is a slightly
improved version, still using an old-fashioned mechanical meter, but running at a more
accurate 100KHz. However, these meters have their limitations; they cannot check for leaky
or shorted caps and the technician must individually discharge each cap before testing. Also,
the cheap test probes add their own capacitance and readings varied depending on the
position that the technician held the probes (and whether or not he or she was sweating!)
The most widely used in-circuit ESR/DCR tester is the CapAnalyzer 88 series by EDS. This
unique meter uses a test frequency higher than most others, automatically discharges the cap
under test, checks for low DCR, then checks and displays ESR on a 20 segment LED bar
scale. It includes a low-capacitance one-handed tweezer test probe, and beeps from one to
five beeps depending on the ESR reading of the cap. Because it is microprocessor
controlled, it has more features and is much more accurate than the older designs. Possibly
its best attribute is a three-colored chart on the front panel that shows typical ESR readings
of good, fair, and bad caps depending on their capacitance. There have been cheap Oriental
copies made for years, so always make sure your CapAnalyzer is purchased from EDS or an
authorized EDS distributor. All CapAnalyzers made after 2001 are series II units, even
though the front labels don't show "series II".
The CapAnalyzer 88A claims 100% accuracy in circuit because of its testing parameters.
The frequency is variable and high enough to make the cap's actual capacity insignificant,
so it measures only the ESR. The high test frequency also helps isolate the cap under test
from the rest of the circuit via the high inductance of the pc board copper foil. This
frequency is also high enough to ignore any coils over 5 uH. ESR testing is done with a
calibrated low resistance at the test point which allows it to compensate for normal circuit
resistance. Both DCR and ESR measurements are under 50 millivolts so that no active
devices are turned on. Therefore only the component at the test point will rerspond.
However, because it checks DCR first, it will alert the technician immediately if the cap or
anything else in that circuit is shorted or leaky, before it checks ESR. This test parameter
(DCR OHMS SET ALERT) is user adjustable from zero to 500 ohms.

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USING THE CapAnalyzer 88A to CHECK ELECTROLYTICS
When the CapAnalyzer 88A is first turned on, after a second of internal calibration checks,
it will briefly check all leds, multi-tone beeper and the battery; then it will flash the OVER
led slowly to indicate ready. The DCR OHMS slider set alert is normally set to about 150
ohms, as shown in the figure. To test an electrolytic, simply hold the tweezer test probe
across the cap leads; polarity does not matter. The CapAnalyzer will chirp once to let you
know that you have a good connection, and the DISCHARGING led will turn on for a
fraction of a second.
The first test is the DCR test, and the CapAnalyzer will show either a NORMAL or LOW
led, depending on the setting of the DCR OHMS SET ALERT slider. If the slider is set to
50 ohms, the CapAnalyzer will sound an alarm and light the DCR LOW led if the DC
resistance is lower than 50 ohms. Most circuits will never show this low normally; however,
in some circuits, the circuit's resistance might be lower or higher. In these cases, you may
set the slider for as low a DC resistance as you expect the circuit resistance to be normally.
For example, on a high power industrial motor controller supply, where the supply must
power a 15 ohm motor, you could set the slider to 10 ohms. The CapAnalyzer would treat
any DC resistance above 10 ohms as normal and warn you if measured DC resistance is
lower than 10 ohms. In fact, you can set the DCR SET ALERT anywhere from a fraction
of an ohm by setting the slider all the way down to 0, to as high as 500 ohms DCR.
Be advised that if you have the slider set higher than 100 ohms and try to measure a very
large electrolytic, the charging time to test the electrolytic may exceed the DCR test period
and you may get a false DCR LOW, or the CapAnalyzer may try testing the cap over and
over because of conflicting test results. Therefore, use 50 ohms as a guideline when
measuring most medium to large electrolytics, and use the values higher than 100 ohms
when measuring small tantalum and surface-mounted capacitors. Surface-mounted
tantalums can become leaky by as high as 500 ohms.
Try this now: set the DCR OHMS slider all the way down to zero and touch the probe ends
to a 10 ohm resistor. The CapAnalyzer will pass the DCR test and show the ESR as 10
ohms. Try the test again with the slider set anywhere above 10 and the DCR LOW led will
come on and the alert will sound continuously. The ESR test will not be done since the DC
resistance is lower than the setting, and the "capacitor" is considered to be shorted.
Now check a capacitor. As you touch and hold the probe across the cap, the unit will chirp
once to indicate testing has started, will pass the DCR test, then will chirp one or more

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times depending on the ESRof the cap. The CapAnalyzer 88A has been designed to chirp
once if the ESR is less than one ohm; Two chirps from one to two ohms, three chirps from
two to three ohms; four chirps from four to eight ohms; and five chirps from 8 to 20 ohms.
The handy three-color chart on the front panel shows typical ESR readings, so if a 2.2 uF
cap chirps three times and shows 3.00 ohms ESR, the chart shows that this is in the green,
good. If you ever used the original CapAnalyzer 88 or 88A, you might have discovered the
unusual case where the CapAnalyzer chirped five times and there was no reading at all; this
usually indicated a good bi-polar capacitor (found in some TVs) which show less than zero.
CapAnalyzer 88A Series II units will correctly show the actual ESR.
As a rule, some caps can show in the yellow area, and may still work adequately. It is up to
the technician to make the decision on whether to replace these questionable caps, or not.
However, any caps that show ESR in the red areas are out of spec and must be replaced. For
capacitors that check as shorted, see the SHORTED CAPACITORS section.
Low-voltage surface mounted caps are usually very poor in quality and even new ones may
show in the yellow areas. Most quality-oriented service companies replace surface mount
caps with conventional caps, as long as they will fit, assuming the technician has the skill to
cut the leads very short and solder them in without melting everything in sight.
Note that if an electrolytic capacitor is in such bad condition to be over 20 ohms ESR, the
CapAnalyzer will treat it as an open circuit and will not even try to test it. The OVER
indicator will continue to flash. Replace these caps, as they are bad, no matter what their
capacity is. If you wish to double-check the test probe, short the probe contacts together
while turning on the unit to activate the InstaESR mode, and the CapAnalyzer will do a
self-test; the top LED should be lit, steady. Wiggle the test cable at each end to check for
frayed strands. You can also check calibration at any time with a 10 ohm resistor: set the
DCR OHMS alert to zero and measure across the resistor; the 10 ohm ESR led should
illuminate. And always make sure the tweezer tips are kept clean or accuracy will suffer.
In some cases, you may find capacitors that are physically leaking, yet they check as perfect.
Although the cap is leaking, it has not leaked enough electrolyte to render it defective and
will still operate perfectly in the circuit...for a while. If you wish to avoid callbacks, replace
them anyway.
NOTE: Although the CapAnalyzer automatically discharges capacitors before testing,
remember that there are limits. If the capacitor is large enough, and there is enough voltage
stored to blow the ends off of the test probes, you will have to replace the probes as well as
the discharge diodes and resistors in the discharging circuit of the instrument. Therefore,
use common sense when measuring large electrolytics that may have a serious charge

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stored. If you damage your unit, it will appear to try to test a cap as soon as it is turned on.
You can easily repair it yourself; go to the website for this and other important information.
QUICK InstaESR TEST
Normally, the CapAnalyzer discharges the cap, then tests for DCR, then measures ESR, as
we have shown. In many cases, you might already know for sure that there are no shorted
capacitors and might wish to save some time by eliminating the full test and just want to
quickly check the ESR. To put the CapAnalyzer 88A in this special InstaESR test, turn the
unit on while shorting the probes ends together. Instead of the multi-tone song, the
CapAnalyzer will only beep twice and be ready for testing. Keep in mind that a shorted cap
will show a low ESR, so we recommend to use only the full test. This feature also uses less
power and will result in much longer battery life.
SHORTED CAPACITORS
A shorted capacitor can cause several individual problems at one time. That's because it can
cause a supply voltage to be low, or missing. The cap you have just checked that shows
shorted might be shorted, or then again, it might be ok. Because various circuits feeding
from the same supply have their own capacitors, the shorted reading will be the same further
down the pcb track across another capacitor. Finding the one shorted capacitor can be
difficult because most DVMs will measure the same short resistance at every capacitor.
That's because most ohmmeters don't have enough resolution (0.001 ohm) to add or subtract
the pc board track resistance from the actual shorted cap's resistance to judge where the
short might be.
Some technicians find these capacitors by cutting the pc board tracks in various places and
measuring the resistances on each side of the cuts. When in the area they believe the short to
be in, they unsolder all suspicious pads and keep measuring until the one shorted part is
found. This is not only time-consuming, but makes a mess of the board. Forget to repair just
one cut or one solder connection, and the unit will be inoperable.
Another method used by some techs is to supply a current-limited voltage source to the
shorted supply and measure the low DC voltages at different points with a sensitive
millivoltmeter. The lowest reading is the location of the short. This works to some degree,
except that the current has to be high enough to get a reading...and maybe high enough to
burn up the board under test, especially if the board uses very thin lands.
Another alternative is to use a four or five digit DVM with milliohm scale which has the
resolution of 0.001 ohm required to measure all of the caps to ground and choose the one

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with the lowest reading to ground. This only works if the cap is shorted--If the cap is only
partially shorted, say over 9.99 ohms, resolution drops to a useless 10 milliohms-or about a
5 inch length of pc board track.
EDS test equipment owners use the LeakSeeker EDS-82 or 89 series to locate shorted, or
even leaky components, with resistance readings from zero to as high as 300 ohms.
The LeakSeeker is a dedicated instrument with only one purpose...to identify the exact
place on a pc board where a given reference resistance is at the lowest reading. The
LeakSeeker automatically calibrates itself to the defective component as soon as it's test
lead is touched anywhere along the pc board track that shows the short or low reading
(under 300 ohms). Then, as the tech touches pads along the track, the Leakseeker beeps
higher or lower depending on whether the tech is getting closer or further from the defect.
This instrument recalibrates itself automatically as you get closer to the defect. The current
version is the EDS-89, which also works with multi-layer boards with ground and power
planes.
LOW BATTERY WARNING
The CapAnalyzer 88A uses four alkaline AAA batteries (6 VDC). Although continuous
operating time is several hours, most users will only need to replace the batteries at three to
six month periods. We advise to measure a few capacitors, then turn off the CapAnalyzer
when you find and replace the bad cap. If left on without being used, a three-minute
warning timer will chirp three times every three minutes.
At 5.1 volts, the LOW BATTERY indicator will illuminate. The unit will still operate for
some time on a low battery, until voltage falls to 4.9 volts, with a slight reduction in
accuracy. Below 4.9 volts, the unit may ignore shorted capacitors, so a good test if you are
not sure is to short the probe tips and see if the DCR LOW led comes on and the alert
sounds, as it should.
Do not attempt to use any external voltage source more than 6VDC. If you need to keep
the CapAnalyzer on continuously, you may send your unit to EDS and a power jack and
specially modified external adapter will be supplied. Alternatively, you can install the AC
adapter easily yourself with a drill and soldering iron; order the optional adapter kit.
If you need help or assistance, we recommend that you check out the CapAnalyzer owners
technical assistance page on our website at: http://www.eds-inc.com/eds88.html for any
last-minute updates, FAQs, and modifications. Replacement tweezer probes are available.

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Declaration of Conformity for European Union
The product listed on this Declaration of Conformity has been tested and verified to comply
with the essential requirements of the Electromagnetic Compatibility Directive 2004/108/EC of 15
December 2004, on the approximation of the laws of the Member States Relating to Electromagnetic
Compatibility (EMC).
Standards to which conformity is declared:
EN 55011: 2007 Industrial, scientific and medical (ISM) radio-frequency equipment -
Electromagnetic disturbance characteristics - Limits and methods of
measurement
EN 61326: 1997+A1:1998+A2:2001+A3: 2003 Electrical equipment for measurement, control and
laboratory use - EMC requirements
Manufacturer:
Merced Electronics under license/permission of Electronic Design Specialists, Inc.
1343 W. 18
th
St
Merced, CA 95340
European Contact:
Eurocoin Ltd
Fortune House
Moxon Street
Barnet Herts
GB EN55TS UK
Description of Equipment:
Product Name: CapAnalyzer 88A series II
Model Number: EDS-88A
Designed and built in the U.S.A.
Electronic Design Specialists, Inc. hereby declares that the equipment specified above conforms to the
protection requirements of the above named Directive(s) and Standards.
David T. Miga, CET President, EDS Inc. April 25, 2008

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Product category 8 and 9 exclusions
Medical devices, and monitoring and control instruments comprise RoHS Category 8 and
Category 9 products respectively. The EU recognizes that these products are manufactured in
small numbers and generally have a long product life. Further, these products are often used in
mission-critical applications where their failure can reasonably be expected to be extremely
disruptive, if not catastrophic. Since the long term effects of lead-free solder, a primary RoHS
objective, cannot be known for a period of at least five years following the directive’s application
to the remaining eight categories, the EU has established at least a temporary moratorium for
Category 8 and 9 products. The EDS CapAnalyzer 88A Series II units made after 2007 use parts
that are RoHS compliant, but may use conventional solder for reliability.
In an effort to gain more insight the EU commissioned a study to assess when and if the RoHS
directive should be applied to Category 8 and 9 products. Released in July 2006, the Review of
Directive 2002/95/EC (RoHS) Categories 8 and 9 –Final Report recommended that Category 8
and 9 products remain exempt from the RoHS directive until 2012 or 2018 depending upon
specific product sub-categories and applications.