EDS LeakSeeker 89 User manual

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ELECTRONIC DESIGN SPECIALISTS
LeakSeeker 89 AutoRanging Fault Locator
OPERATIONS MANUAL
Rev 8/28/2020
Please read this manual completely before trying to use the LeakSeeker for the first
time. There is a short tutorial on page 6 that will guide you on your way to the “Ah-
Hah!” moment of understanding. Skipping the tutorial will make your understanding
far more difficult. Watching the videos at www.eds-inc.com/leak.html is advised.
This unit is designed to be used on a non-powered circuit, as it supplies its own precise
test voltages. Be sure power is disconnected from the unit under test, or your
LeakSeeker may be damaged!
It is advised to check the Technical Assistance page at www.eds-inc.com for any last-
minute additions to this manual and to answer frequently asked questions.

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Preliminary
The LeakSeeker model EDS-89 will locate a shorted or leaky component or any other
shorted condition (such as a pinched wire or solder bridge) with a short resistance value
from zero to 300 ohms, to the exact spot on a pc board. If the unit has multiple pc boards,
LeakSeeker will first identify which board contains the defective component, then will
guide the technician directly to the location of the defective component on that board.
The EDS-89 version is an updated version of the original LeakSeeker EDS-82 series with
three sensitivity modes, all fully automatic. Tests are done simply by touching the solder
pads along a “shorted” foil trace and the pad with the highest pitch marks the defect.
This unit includes a universal AC adapter with a 2.1mm plug. The internal regulator in
LeakSeeker allows it to run from any AC or DC adapter or battery from 9 to 25 volts AC
or DC, as long as it has a 2.1mm plug.
How the Leakseeker works
The EDS-89 LeakSeeker pinpoints the exact location of a shorted or leaky component by
comparing the resistance at different component solder pads along a shorted pc foil trace,
and subtracts the foil's milliohm resistance from the value of the defective component.
Therefore, there is a different reading at each pad, although by a very small amount, with
the lowest reading at the short. Leakseeker consists of a 16 bit self-calibrating digital
comparator with a range of zero to 300 ohms, auto memory, and a variable gain
comparison circuit with visual and audible indicators. Initial search for a shorted
component automatically starts at the LeakSeeker's maximum range and counts down to
the resistance of the defective component, within a "window" that is indicated by nine
small distance LEDs. It also uses a variable pitch tone, which will be at its highest when
the test probe is touching the pad where the resistance is lowest.
LeakSeeker can use one of two different test methods to locate the defect. The NORMAL
test causes a precise voltage/current to appear at the test PROBE, and as the technician
touches each pad, the small difference in the voltage/current readings is translated into
the change of the beep pitch and distance LEDs. This test method is ideal for finding the
location of typical “dead” shorts under a few ohms.
The 3-WIRE test is used when the readings are confusing, for example, if the "short" is
actually many ohms, and a large electrolytic capacitor is somewhere along the trace.
Instead of a steady tone, the pitch may constantly change as the capacitor tries to charge
or the leaky defective component warms up, making stable readings impossible. The 3-
WIRE test separates the precise voltage reference +REF from the PROBE port. It is
more difficult to use, so the technician should have a thorough understanding of the

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normal testing methods first.
First, some important notes that you need to remember:
LeakSeeker recalibrates itself automatically to a new range as you get closer to the defect,
as ohms get lower. If you get further from the short and resistance goes higher, a lower
pitch of the tone, and eventually no tone at all and the lowest red indicator will be the
only indication. If you loose your way, or accidentally touch the wrong pad, you can push
RESET and LeakSeeker will re-calibrate itself again, as soon as the PROBE is touched
to the correct pad. Remember that all tests must start by pushing the RESET button to
clear the memory.
During the normal test, you would touch any pad along the “shorted” foil and allow
LeakSeeker to recalibrate automatically as you get closer to the defect. However, if all of
the solder pads seem to have the same tone because of the low resistance of the ground
plane power source of a multi-layer board, using a higher GAIN allows you to increase
the resolution many times.
Normal testing
You should be sure that you are looking for a shorted or leaky part by verifying that the
pc board trace you are about to test shows a suspiciously low ohms reading. A quick
method for checking any type of unit for shorts is to simply measure the resistance across
the largest main filters in the power supply with your ohmmeter. In a normal circuit, you
will usually see the cap charging up to several thousand ohms. If you own a CapAnalyzer
88, set the LOW DCR warning slider to 50 ohms. Any cap that shows 50 ohms or less is
probably the supply line that feeds the shorted component. Be advised that using an
ordinary DVM ohmmeter will not find active shorts. Instead, use the CapAnalyzer or
LeakSeeker as you would an ohmmeter. Normal circuit conditions would produce no
warnings, while passive or active shorts 300 ohms or less will make LeakSeeker calibrate
to the short and give you a steady reading.
For example, a normal power supply output usually shows several thousand ohms, after
the filter caps finish charging. If you feel that you have a problem with the supply
because voltage readings are low while the unit is powered up, or CapAnalyzer warned
you with DCR TOO LOW, remove power and use an ohmmeter across the cap to see if
the reading is lower than 300 ohms (the maximum range of the LeakSeeker) to ground.
Typically, most good supplies show resistances in the thousands of ohms while most with
"shorts" will show just a few ohms, or even less than an ohm. The exception to this

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instance is when you suspect an active short, where a supply is pulled down by a
component that does not show shorted with your ohmmeter. This can happen when, for
example, a component shorts, but is powered through a diode. Although your ohmmeter
cannot measure past the diode, the LeakSeeker (and CapAnalyzer) can. A steady tone
after the LeakSeeker calibrates indicates that it found a suspicious reading under 300
ohms and your search can go on. If it simply chirps or gives no reading at all, then no
short (active or normal) was found.
Getting Started
Look at the GAIN switch. Notice that the lower gain setting is best for thin pc foil traces,
and should be your first choice. If you notice very little pitch changes as you hop from
pad to pad, you can raise the GAIN, as the foil traces might be thicker. You would use
the highest GAIN setting for very thick traces or multi-layer boards with ground planes.
In the NORMAL test, the BLACK ground wire alligator clip is connected to the best
ground available, preferably at the power source. The connection must be of high quality
or the results will be misleading. You can ignore the alligator clip and solder the bare
wire (behind the alligator clip) to ground to eliminate this source of errors.
Push the RESET button to let LeakSeeker know to start a new search. The test probe is
then touched on a solder pad anywhere along the pc board copper trace that you believe a
shorted or leaky component is soldered to. If the board is dense, you might use a thin
Sharpie marker to outline the trace, to prevent confusion so that you don’t accidentally
touch the wrong pad.
As you hold the test probe on the first pad, LeakSeeker will beep at its highest pitch and
light the WAIT lamp brightly for a few seconds as it ramps quickly down to the short
value. Be patient. As it gets closer, the search will slow, the WAIT LED will flash dimly
and you will hear the pitch clicking step by step as it gets a few milliohms closer and
closer. When it has calibrated, the pitch will be low and steady and one (or a group) of
the nine distance LEDs will be lit. Touching the test probe to the next solder pad along
the pc trace should make the pitch higher or lower, depending on whether you are moving
in the correct direction. The distance lamps will also give rough indications that you are
getting closer or further from the defective component. As you touch the probe from pad
to pad in the correct direction, the beeps will get higher in pitch and the distance LEDs
will go CLOSER > to the green LEDs. As you get out of range of the window, the
WAIT LED will come on as LeakSeeker recalibrates the window. If you get further from
the short, the LEDs will reverse toward the red LEDs and the pitch will get lower. You
should always make it a habit to go back one pad after each new pad test to make sure the
pitch is higher on the new pad and lower on the old pad, as LeakSeeker will recalibrate
very quickly and you might not notice.

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If you accidentally touch the probe to a wrong pad not on the shorted circuit, like maybe
ground, and LeakSeeker notices the huge change, it intentionally waits a second before
accepting the huge change and recalibrating. The delay is intentional; if you accidentally
touched the wrong pad (like a ground), this delay gives you the time to change your mind
as long as you lift off of the pad before the WAIT LED comes on and recalibration is
complete. You should always double-check your progress by touching the previous pad--
-the pitch should be lower than the pad closest to the short. If you goof, just press
RESET and start off the last valid solder pad.
On older boards with large traces, or on multi-layer boards with groundplanes, you may
find that many pads close to each other may have the same pitch. Use the highest GAIN
setting and now you will see and hear a slight change between the two pads. The pad with
the highest pitch is your objective. When the tone no longer changes and the WAIT LED
is off, the window is perfect.
As you touch each pad, remember to always go back one to double-check that the tone is
lower (or gone completely as that window is now long gone). At some point, the beep
will be highest in pitch at only one pad along the trace. This is the short, and may be the
location of the defective component. If you continue past this pad, the pitch will start to
go lower and the distance indicator will start to head towards the red indicators. If you
backtrack, the pitch will always be highest at the pad with the lowest resistance, and of
the possible defective component.
But what if the highest pitch can’t be the bad part?
If the highest pitch comes from a pad that is a jumper or wire, or coil or transformer, for
example, a component that is supposed to conduct, this means that the defect is probably
on the other side of the component, in another area of the board. For example, if you are
tracing a short at the collector of the horizontal output transistor and find that the highest
pitch is at the flyback transformer primary, this does not necessarily mean that the
transformer is shorted; the short may be on the other side of the winding, at the B+
supply. Follow it like a detective, as you may find that you may be jumper-hopping, coil-
hopping, possibly even board-hopping, for example from the HV board, to the supply
board and so on, to where the bad part actually is. The obvious parts that could be bad are
parts that should never show as a low resistance in the first place, such as a capacitor,
cathode of a diode, B+ pin of an IC chip and so on.
Using the Hot/Cool thermal test method
If the defect is several ohms, you can search for the defective component in another,
much easier way. To keep your hand free to hold a can of freeze spray or a soldering iron
or hot air blower, use the extra plug-in test cable supplied with LeakSeeker that has the

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solder wire tip, plug it into the REF+ port, and solder the tip to any pad along the shorted
trace. The test mode switch remains in the NORMAL position, which joins the REF+
and PROBE ports together. Press the RESET button and wait for a stable reading.
Higher resistance defective components are always thermally responsive. You can use a
can of freeze spray to spray each component on the board while the solder tip test cable is
soldered on the suspected trace. The spray will make the LeakSeeker change quickly in
pitch when the defective component is sprayed.
3-Wire testing
3-Wire testing is used for times when Normal testing becomes difficult. In these cases, a
component may not be shorted, but just leaky; perhaps 50 or more ohms, and a capacitor
along the trace tries to charge each time the test probe is touched to a pad. Instead of
steady tones, the LeakSeeker will chirp from high to low, or the pitch will vary, making
testing very difficult in the NORMAL position as you wait forever for the pitch to get
stable, but the 3-Wire test will separate the +REF from the PROBE port, and allow the
circuit to stabilize under power. Only use the 3-wire test for higher-ohm shorts over about
10 or 15 ohms and when normal testing is too difficult.
Solder the +REF wire solder tip to the normal source of the power in the supply line you
are troubleshooting, for example, at the output of the power supply at the big electrolytic
that shows a short to ground. This is important, as the 3-Wire test does not allow testing
to start anywhere on the board as the NORMAL testing allows. Make sure the mode
switch is in the 3-WIRE test mode. You must start probing at the normal source of
power, like at one end of the trace by the large power supply capacitors. Allow about 15
seconds for all voltages, currents and temperatures to stabilize, push the RESET button,
then touch and hold the test PROBE at the starting point where the +REF is soldered,
and allow LeakSeeker to calibrate. Then touch each pad along the bus and proceed as you
would in the NORMAL test. Each reading should now be quick and easy since the
special signal from LeakSeeker +REF now is no longer changing.
As you proceed, just as in the NORMAL test, the pitch of the tone and distance
indicators will guide you towards the defect. As you probe different branches, you will
find that some branches do not have any changes from pad to pad. That is because there
are no problems in that branch. Go back to the fork and try another branch.
At some point, you will reach the defect and pass it, and the distance indicators and tone
pitch will again no longer change, just like the previous branches that had no problems.
The first pad on the branch that is highest in pitch is the location of the defect. Going
back towards any other branch will cause the tone to get lower, and going forward will no

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longer cause the highest pitch to change. Therefore, be sure to notice the exact location at
which point the readings no longer change as you pass the defect. The exact location of
the first pad that has the highest pitch will be the exact location of the defect. All pads
beyond this point will have the same pitch as the first pad of the highest pitch. You can
verify the defect by using a blast of freeze spray or directed heat on the suspicious
component. LeakSeeker will change pitch drastically only when the defective part is
cooled or heated.
Tutorial
To best be familiar with LeakSeeker, try this little experiment. It will give you the
direction and understanding in real time of how to use LeakSeeker. You will intentionally
create a defect by soldering in a low-value resistor across a capacitor in a power supply
trace, and then use your LeakSeeker to find it.
On an old pc board or discarded electronic component, locate a power supply trace on the
main board and check the resistance to ground. You will see how a normal circuit should
show, probably a few thousand ohms. Now, solder in a low-value resistor across a large
capacitor, or maybe somewhere further down the trace to ground, to simulate a leaky
capacitor. For example, you could solder a 4.7 ohm resistor to ground at an integrated
circuit B+ or small filter cap. (Of course, don't power up the unit, or you might damage
its power supply). Use your DVM or ohmmeter to verify that you get the same 4.7 ohm
reading to ground, everywhere along the trace.
With the LeakSeeker power switch in the NORMAL test, push RESET once. Start at
some distance from the “short” resistor, along the same foil. Use a Sharpie marker if the
trace is very thin so you don’t get lost. You should follow the instructions for the
NORMAL test and follow the LeakSeeker's advice, tracing a path along the pcb foil trace
pads, wires, jumpers and connectors, and end up at the resistor that you soldered in.
(Don't forget to remove the tutorial resistor from your experiment when done!)
As you progress, you will get the feel and the personality of your LeakSeeker. Try the 3-
WIRE test method only after you have mastered the NORMAL test, as this test is more
difficult. You’ll usually only need this test with shorts higher than 10 ohms anyway,
which are rare.
IN CASE OF TROUBLE
If you accidentally forget to remove power from the unit under test, the power would try
to feedback into the LeakSeeker and cause damage. There are two 0.47 ohm fusible
resistors and one 9 volt zener diode soldered to the board near the test probe, clearly
marked on the board. These are designed to self-destruct and protect the LeakSeeker's

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electronics. There are indications that these protection devices have done their job;
LeakSeeker will immediately beep and try to calibrate to nothing as soon as it is turned on
and the RESET button is pressed if the zener diode is shorted, or you would get no
function at all if the fusible resistor is open.
60 DAY MONEY-BACK GUARANTEE
EDS, Inc. guarantees that the user may return this product to original place of purchase
for a full refund within 60 days of receipt under the following conditions:
1: The product must be undamaged and returned in the same condition as received and
with the original packing material. A copy of the bill of sale is required. You must call
the reseller for a return authorization number. You are responsible for return shipping
charges and for providing correct insurance coverage. Units received damaged will be
returned to you. Any missing probes or hardware will be deducted from the refund.
Original shipping costs will be refunded only if the unit has a factory defect.
2: All EDS products are unique and some effort is required to learn to use an unfamiliar
new device. It is expected that you attempt to use and learn this product for at least two
months, and to read and follow the directions in the owner’s manual. If you are confused
about any instructions in the manual or need any assistance, please contact your
distributor or EDS-Inc for assistance and make an honest effort to learn to use the
product. If the product proves to be too difficult for you to learn, feel free to make
comments or suggestions to help EDS improve the product or revise the owner’s manual
when you return your LeakSeeker.
THREE-YEAR LIMITED WARRANTY
EDS, Inc. warrants this product to be free from factory defects for a period of three years
from date of purchase. A copy of the original bill of sale is required for any claims. The
customer will call for return authorization and mail the unit to EDS for repair or
replacement. This warranty does not include any damage caused by shipping, abuse,
lightning, or incorrect testing procedures. Test probes or any other wires or cables are not
covered under this warranty. EDS shall not be responsible for any action or consequential
damages caused by the user, and assumes no responsibility for liability due to the actions
of the user. The user/operator assumes complete responsibility in using this product and
is expected to conduct their operating procedure in a safe and professional manner.

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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, as amended July 2011, on the approximation of the laws of the
Member States Relating to Electromagnetic Compatibility (EMC).
Standards to which conformity is declared:
EN 61326-1, CISPR 11, EN 55011 Electrical equipment for measurement, control and
laboratory use - EMC requirements
Manufacturer:
Electronic Design Specialists, Inc.
21621 Reflection Ln
Boca Raton, FL 33428
European Contact:
Eurocoin Ltd
Fortune House
Moxon Street
Barnet Herts
GB EN55TS UK
Description of Equipment:
Product Name: LeakSeeker 89
Model Number: EDS-89
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. June 9, 2013
Product category 9 exclusions as amended July 2011
Industrial Monitoring and Control Instruments are considered RoHS Category 9 products. The
EU recognizes that these products are manufactured in small num ers and generally have a
long product life. Further, these products are often used in mission-critical applications where
their failure can reasona ly e expected to e extremely disruptive, if not catastrophic. The EU

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has esta lished at least a temporary moratorium for Category 9 products until July 2017. EDS
products use parts that are RoHS compliant, ut may use conventional 60/40 solder for
relia ility at certain junction points.
RoHS2 DIRECTIVE 2011/65/EU
http://www.ce-mark.com/RoHS2.pdf http://www.ce-mark.com/Rohs2 final.pdf
www.eds-inc.com