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Question about failing starter capacitors on electric motors

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Bob Parker

Jan 1, 1970
0
Thanks Bob. I will go and have a look today. Its one of those tools
that occasionally you say 'I wish I had one of those'. Whilst i very
rarely have anything to do with hardware it does still arise from time
to time.

Are DSE clearing out all there kit stock?


Good question - it sorta looks like they might be, doesn't it?
 
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Bob Parker

Jan 1, 1970
0
Sounds like they need more shelf space for the farting ashtray lines ;-(


You might be thinking of Jaycar? ;)

In the case of DSE it'd be MP3 players, cordless phones and TomToms
etc...
 
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Bob Parker

Jan 1, 1970
0
There were two of each on the shelf in the Box Hill (Melb) store,
tagged at $49.95 - but the counter check showed they were $25.
Thanks for the heads-up, I almost bought one six months ago at >$70.
Now I have a MK2 to build.

What're the main differences in capability between the MK1 and MK2?

The Mk2 version can do some basic checks of its own circuitry if
there's a problem getting it working after construction. Generally
irrelevant if you know how to solder and put components in the right
place. ;)
Also the automatic switch-off time is 3 minutes as against 2 minutes
for the Mk1. Mk1 is powered by a 9V alkaline battery while Mk2 uses 6 x
AAA cells. Mk2's front-panel typical ESR value chart is more up to date.
There's no difference in their circuit boards or components.
What else can it be used for apart from testing electro's?

Phil's already given some possible uses. The kit notes have more
suggestions (page 13). You can download it as a 1.3MB .pdf file from:
http://members.ozemail.com.au/~bobpar/k7214.pdf
There's also a lot of suggestions/hints from users at:
http://members.ozemail.com.au/~bobpar/esrhints.htm

Hope this answers your questions.



Cheers
Bob
 
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Bob Parker

Jan 1, 1970
0
Hi Bob,

I came across this review website and wondered if you think the
comments and tests on your design are fair?

http://www.anatekcorp.com/testequipment/esrcompar.htm


G'day Geoff,
Reasonably fair. What it doesn't mention is that you don't need a
lot of accuracy to identify which electrolytic cap's causing a problem
in a circuit. Its measured ESR will be so far above what the chart says
(often not even giving a reading because it's >99 ohms), that it'll
stand out like the proverbial(s). That's why the meter's only got a 2
digit display.
I don't agree that there's a problem with the component quality.
No-one's ever complained to me about it.

Bob
 
B

Bob Parker

Jan 1, 1970
0
"Geoff C"



** How about this quote then:

" But a good 1 ufd, 200 volt aluminum electrolytic can have an ESR of 100
ohms or more. That is beyond the measurement range of all of the meters
listed above! "


I just checked a number of old but unused electros bought from WES in a bulk
pack.

Values ranged from 0.47uF to 1.0 uF with voltages from 250 to 400 volts -
physical size all about 12mm by 8mm dia.

None tested more than 30 ohms on Bob's Mk1 meter.

Any that test over 100 ohms are FAULTY !!!


........ Phil


I agree with Phil!

Bob
 
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Phil Allison

Jan 1, 1970
0
"Bob Parker"
I don't agree that there's a problem with the component quality.
No-one's ever complained to me about it.


** But what folk here don't know is that Bob is very large, heavily
tattooed and very mean looking .....





........ Phil ;-)
 
B

Bob Parker

Jan 1, 1970
0
** But what folk here don't know is that Bob is very large, heavily
tattooed and very mean looking .....


....... Phil ;-)


DAMN!!!!
I was hoping no-one would identify me at the aus.electronics
get-together.
Now the cat's outta the bag.


Bob
;-)
 
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Tom

Jan 1, 1970
0
Bob said:
If you decide to get one, be aware that DSE's selling the Mk1 (1996)
version of the meter for the same price, and the Mk1 and Mk2 cartons
tend to get mixed up on the shelf.
That's true, both Mk1 and Mk2 are the same price, I wanted to get one yesterday and first DSE shop I went had only Mk1, had to drive to a second one but it was worth it as they had Mk2 (and few more cheap kits in stock).
Tom
 
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Bob Parker

Jan 1, 1970
0
That's true, both Mk1 and Mk2 are the same price, I wanted to get one
yesterday and first DSE shop I went had only Mk1, had to drive to a
second one but it was worth it as they had Mk2 (and few more cheap kits
in stock).
Tom

Well done! I hope the meter pays for itself before too long. :)

Bob
 
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Tom

Jan 1, 1970
0
Bob said:
Well done! I hope the meter pays for itself before too long. :)

At that price it is well worth buying even if I don't use it too often and this kit stands out of the rest - good quality PCB with overlay and nice front panel. Good work Bob!!!!

Tom
 
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Bob Parker

Jan 1, 1970
0
Hi Bob,

I gave up, and got my Dad (who lives in Brisbane) to get me one and mail
it over. Thanks :)

Cheers
Terry

Hi Terry
Postage to NZ from the Western Island shouldn't be too pricey so
you'll still get it at a good price. ;-)
I hope it'll pay for itself in time saved.

Cheers
Bob
 
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Phil Allison

Jan 1, 1970
0
"Bob Parker"
I don't agree that there's a problem with the component quality. No-one's
ever complained to me about it.


** I picked up an ESR Meter mk2 kit from DSE's "Mid City Centre" store on
Saturday - for a mere $25 it means I now have a spare. All the components
look to be of good quality and the instructions even printed on decent (
glossy) paper for once.

However, the LTS5503AE displays included are rather dim - IMO not
useable in the sort of light most would have on a service bench. My old one
used the LSD5114s and is quite OK in such light.

Farnell have common cathode HE red displays from Kingbright ( # 622-205 )
for about $1.40 each + gst that should be a lot better.




........ Phil
 
D

David L. Jones

Jan 1, 1970
0
"Bob Parker"




** I picked up an ESR Meter mk2 kit from DSE's "Mid City Centre" store on
Saturday - for a mere $25 it means I now have a spare. All the components
look to be of good quality and the instructions even printed on decent (
glossy) paper for once.

However, the LTS5503AE displays included are rather dim - IMO not
useable in the sort of light most would have on a service bench. My old one
used the LSD5114s and is quite OK in such light.

The Mk2 kit I got the other day also has the dim display, pretty
annoying. But considering that I will rarely use such a meter it's not
a big deal for me. But I can imagine it would drive a tech who uses it
every day nuts.

Dave :)
 
B

Bob Parker

Jan 1, 1970
0
The Mk2 kit I got the other day also has the dim display, pretty
annoying. But considering that I will rarely use such a meter it's not
a big deal for me. But I can imagine it would drive a tech who uses it
every day nuts.

Dave :)


OK, now I can say I've had complaints about component quality. :-(
In the original project, I specified Kingbright SC56-11SRWA 'super
red' high efficiency displays. In fact when Jaycar were making the kit,
they did the right thing and included them. You can almost read a Jaycar
ESR meter in direct sunlight.
DSE decided to supply those considerably dimmer orange displays they
were already selling. I was never very happy about their brightness.
Looks like they've gone to including even lower efficiency displays now.
The Kingbright SC56-11EWA ones Phil's found appear to be a later
version of the original SC56-11SRWA and should be brilliant. Thanks for
the info, Phil.

Cheers
Bob
 
B

Bob Parker

Jan 1, 1970
0
it should do; 30 minutes will suffice. at present I use a signal
generator, a little PCB I made and a small amount of arithmetic. But at
that price, its silly not to get one.

interestingly enough, I want it to measure motor run caps. I'm finishing
off a design now that starts and runs three-phase SCIMs on a single
phase supply, with no inrush (which is a fairly good trick). Suffice it
to say I use +24Vdc and -900Vdc to achieve this, along with some baby
1200V 30A SCRs.

besides, arent we east Tassie?

Cheers
Terry


I never was too good at geography. :)
Good luck with your design, and just be careful to discharge those
caps before you touch them, let alone measure their ESR....

Cheers
Bob
 
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David L. Jones

Jan 1, 1970
0
OK, now I can say I've had complaints about component quality. :-(

Well, if you want to get picky then there were also some incorrect
pitch capacitors supplied, and some of the resistors were incorrect
tolerance. Also, I got Orange 3mm LEDs with Red 7-seg displays.

Dave :)
 
B

Bob Parker

Jan 1, 1970
0
Well, if you want to get picky then there were also some incorrect
pitch capacitors supplied, and some of the resistors were incorrect
tolerance. Also, I got Orange 3mm LEDs with Red 7-seg displays.

Dave :)


Thanks for the feedback... I like to know what people building the
kits are experiencing, so I know what they're talking about if they
contact me about problems.

Bob
 
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David L. Jones

Jan 1, 1970
0
Thanks for the feedback... I like to know what people building the
kits are experiencing, so I know what they're talking about if they
contact me about problems.

Bob

Oh, and your software fault diagnostics works a treat too. Built mine
in haste during lunch hour at work and my brain wasn't switched on, so
accidentally installed a wrong value resistor and got the F1 error
message :-/
Yes, you can build it and test it (and troubleshoot it) in under 1
hour, and still have time to each your lunch.

Dave :)
 
B

Bob Parker

Jan 1, 1970
0
Oh, and your software fault diagnostics works a treat too. Built mine
in haste during lunch hour at work and my brain wasn't switched on, so
accidentally installed a wrong value resistor and got the F1 error
message :-/
Yes, you can build it and test it (and troubleshoot it) in under 1
hour, and still have time to each your lunch.

Dave :)


I did the self-test function to try and reduce the number of e-mails
I was getting from people with construction problems (mostly solder
whiskers).
It was amazingly successful.... I hardly get any e-mails like that
now. :)

Bob
 
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