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Test report:
The Peak Atlas ESR tester
Electrolytic capacitor ESR testing has done a lot to help and to speed up
CE equipment servicing in recent years. Peak has recently introduced a
new tester, Model ESR60, with several interesting features. Eugene
Trundle has given one an extended test
The Peak Atlas ESR
tester Model ESR60.
I
n the past few years electrolytic of conventional fault diagnosis by more cost-effective designs. But
capacitor ESR (Effective Series testing all, or most, relevant elec- equipment designers seem to have a
Resistance) testing has become a trolytic capacitors in a piece of blind spot when it comes to the
common topic in this magazine. equipment and replacing any that physical design, component specifi-
There have been articles and con- produce an excessive resistance cation and layout of chopper power
structional projects, amongst which reading. Very often this will cure a supplies. The combination of a rela-
there was an excellent practical fault that could be producing very tively cheap capacitor, a high ripple
design by Alan Willcox in last strange symptoms – ones that, espe- current and the close proximity of
December’s issue. This is the one I cially in digital equipment, you hot components will often lead to
have been using in my workshop might not readily attribute to a faulty failure sooner or later, despite the
lately, with great success. electrolytic capacitor. Typical exam- fact that the equipment gets out of
In practice the ESR of an elec- ples might be DVD players and the factory door OK and usually sur-
trolytic capacitor is much more sig- satellite set-top boxes for which we vives through the one-year warranty
nificant than its actual capacitance have no service manual or circuit period! Experienced technicians
value, especially in the signal-cou- diagram. have learnt what type of capacitor, in
pling and supply-decoupling roles Electrolytic capacitor failure is which place (usually the power-sup-
such capacitors perform in the sort becoming one of the most common ply section), to go for first in carry-
of equipment we handle. Once causes of breakdown in consumer ing out a general test with an ESR
you’ve got used to working with an electronic equipment as plugs, sock- meter.
ESR tester you would never want to ets, switches and similar connectors Apart from the DIY designs that
be without one. A testimony to the are designed out, as mechanics are have appeared in this magazine, I
usefulness of an ESR tester is that I simplified, as ICs and their jointing know of two sorts which are avail-
and others in our workshop are often become more reliable and as compe- able commercially: the analogue-
able to short-circuit (!) the business tition and price-cutting demand ever meter reading Capacitor Wizard that
460 June 2005 TELEVISION
costs about £145, and the Electronic measurement is more likely to be resistance had increased.
Design Specialist type, with a 20- accurate with the component isolat- When I came to check the tester’s
segment LED readout, that costs ed. For further details, see Table 1. vulnerability to damage from a
about £175. Both are effective, charged capacitor, I used a bench
though with the former, care is On test power supply to charge an out-of-
required to discharge the capacitors This little gizmo kept me company circuit capacitor to just the specified
before connecting them for test. I on the bench and in the field for sev- ‘abuse’ level. I then connected it,
don’t know of any that have a digital eral weeks. At the end of the assess- with some trepidation, to the tester.
readout or a facility for measuring ment I took a bunch of good and duff No harm came from this, but it’s
the capacitance of the component electrolytic capacitors home and obviously best to ensure that the
being tested. played with the meter at length. I capacitor being tested has been dis-
found it satisfactory in every way, charged. The internal discharge
Description once I had made some needle-point- should, I feel, be regarded as emer-
Peak Electronic Design has been ed test probes to connect to the mini- gency protection rather than being
making small test equipment items crocodile clips provided – these relied on for each test, especially as
for some years, in hand-held form. probes facilitated easier connection to there’s a limit of 40V with capacitors
They come in curvy little cases, size capacitors in situ. The long test leads of value higher than 10µF. Better
10 x 7cm, with a digital-readout supplied were appreciated in use safe than sorry!
panel. A colour-coding system is with, for example, a large-screen TV
used for different functions, general- set, especially in the field where the Verdict
ly red for cable testing, yellow for instrument needs to be out in the The introduction of the Peak Atlas
LCR checking, orange for triacs and light for easy reading. For situations ESR60 will, I believe, force a
blue for semiconductor devices. This like this an ‘eyes-off’ indication of rethink amongst makers and sellers
one, as the accompanying picture low ESR, in the form of a bleep, of ESR testers that cost twice as
shows, is purple. It’s powered by an would have been useful, cutting in at much or more. This one is smaller,
internal 12V alkaline battery, of the say resistance values below 1Ω or lighter, has more features and is
sort used in car-security fobs. 0·5Ω. It would also have been good more useful. I never thought that
There is only one control, an on to have had ESR readings of up to anything would prise me away from
key that initialises the instrument. 20Ω, to take into account low-value, my trusty analogue ESR tester, but
After that it takes a few seconds to high-voltage capacitors such as the this one has done it!
go through a test cycle. Any DC 1µF and 2·2µF, 100-400V types typi- Excellent indeed, and designed
charge (within reason, see the speci- cally found in the ‘kick-start’ circuit and priced for the service technician
fication table) is first removed, after in a chopper power supply – they – unlike some pieces of test equip-
which the meter takes about eight often fail. These are minor points ment that have come to my notice
seconds to calculate the electrolyt- however. lately.
ic’s ESR and capacitance values, The meter performed very well in
which are then shown simultaneous- all respects. I have no reason to Availability
ly in the two-line LCD panel. The doubt the accuracy of either the ESR The Peak Atlas ESR tester Model
instrument shuts down automatically or the capacitance readings, and the ESR60 costs, with delivery, £67.23
after a further twenty seconds – simplicity of operation is a great plus VAT, a total of £79. A one-year
there’s no need for an off switch! benefit. The analyser’s ability to read guarantee is included. It’s available
ESR from 0-10Ω can be read, with a capacitance as well as ESR showed from Peak Electronic Design Ltd.,
resolution of 0·01Ω below 1Ω and clearly that an electrolytic capaci- Buxton, Derbyshire. The phone
0·1Ω above 1Ω. The capacitance tor’s value in µF can remain correct number is 01298 70 012 and the
measuring range is 1-22,000µF, with though its internal resistance is email address
an accuracy of about ±4%. The test excessively high. But I found a few sales@peakelec.co.uk
frequency is 100kHz, current 20mA capacitors, mainly old ones, whose There’s a website at
(short-circuit) and voltage 2·5V value had decreased as their series www.peakelec.co.uk
(open-circuit).
The test leads supplied are Table 1: Peak Atlas ESR60 specification
450mm long, and each has two con-
ductors, one to apply the test wave- ESR measuring range 0-10Ω
form and one to measure the result. Resolution <1Ω, 0·01Ω; >1Ω, 0·1Ω
This Kelvin arrangement increases Accuracy <1Ω, ±2%, ±0·02Ω; >1Ω, ±2%,
the accuracy by removing the effect ±0·2Ω
of lead inductance. Inside the unit I Capacitance range 1-22,000µF
found a rugged construction on a Accuracy ±4%, ±0·2µF
fibreglass PCB, with half a dozen Peak test current into s/c 20mA
ICs, a precision crystal, the LCD Peak test voltage across o/c 2·5V
panel and a handful of other items. Operating frequency 100kHz
The only internal parts that appear to Abuse voltage <10µF, ±400V; >10µF, 40V
have a finite life-span are, ironically, Battery GP23A 12V alkaline
a couple of surface-mounted, 100µF, Battery voltage range 12–8·5V, with low-battery warn
16V electrolytic capacitors! They ing at 8·5V
would be easy to replace should this Inactivity time-out 10 seconds
ever be necessary. Dimensions 103 x 70 x 20mm (w x h x d)
The instrument can be connected Operating temperature range 10-40°C
to the capacitor under test either way Accessories supplied Battery, leads and instruction
round, and will test capacitors in or book with ESR value table
out of circuit for ESR. Capacitance
TELEVISION June 2005 461
