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Main
Date: 14 Mar 2007 11:36:36
From: Randy G.
Subject: Craftsman mini multimeter with K thermocouple
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Craftsman Digital Mini Multimeter
>http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=TOOL&cat=Electrical+Shop&subcat=Multi-Meters%2C+Testers+%26+Accessories&pid=03482345000
(http://tinyurl.com/3byoa7)
Comes with type K thermocouple
$9.99 and free in store pickup
No experience with it- just thought about folks looking for a cheap
thermometer, etc.
Randy "sorry, it's not free" G.
http://www.EspressoMyEspresso.com
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Date: 21 Mar 2007 09:13:37
From: daveb
Subject: Re: Craftsman mini multimeter with K thermocouple
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On 21, 10:41 am, pltrgyst <pltrg...@spamlessxhost.org > wrote:
> On 21 2007 06:03:49 -0700, "daveb" <davebobbl...@gmail.com> wrote:
>
> >I think it would be best to relegate this little TOY to the household
> >toolbox, to measure volts and ohms, etc.
>
> ... and to get a free thermocouple thrown in for use with your better multimeter
> (Fluke, etc.). 8;)
>
> -- Larry
Yeah, all in all -- not a bad deal.
:)
[except that it inflates the trade deficit with (red) China! ]
remember when it was called that?
dave
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Date: 22 Mar 2007 20:51:19
From: Barry Jarrett
Subject: Re: Craftsman mini multimeter with K thermocouple
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On 21 2007 09:13:37 -0700, "daveb" <davebobblane@gmail.com > wrote:
>[except that it inflates the trade deficit with (red) China! ]
>
>remember when it was called that?
it isn't any more?
--barry "chicom"
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Date: 21 Mar 2007 06:03:49
From: daveb
Subject: Re: Craftsman mini multimeter with K thermocouple
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>
> On the serious side, an inaccurate measurement would not be bad as long as
> it was consistent in it's performance. The down side would be if you were 2
> degrees high on one measurement, and 2 degrees low on the next.
>
> --
>
I think it would be best to relegate this little TOY to the household
toolbox, to measure volts and ohms, etc.
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Date: 21 Mar 2007 10:41:49
From: pltrgyst
Subject: Re: Craftsman mini multimeter with K thermocouple
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On 21 2007 06:03:49 -0700, "daveb" <davebobblane@gmail.com > wrote:
>I think it would be best to relegate this little TOY to the household
>toolbox, to measure volts and ohms, etc.
... and to get a free thermocouple thrown in for use with your better multimeter
(Fluke, etc.). 8;)
-- Larry
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Date: 17 Mar 2007 09:35:21
From: rasqual
Subject: Re: Craftsman mini multimeter with K thermocouple
|
On 16, 5:24 pm, "daveb" <davebobbl...@gmail.com > wrote:
> On 16, 6:09 pm, "rasqual" <scott.qua...@gmail.com> wrote:
> > OK, so if I have a TC already that has a mini-connector for
> > thermocouples, how am I supposed to adapt it to the plug in the meter?
>
> > Anyone have any sources for such non-standard thermocouple plugs that
> > can be easily connected to TC wire?
>
> > - S
>
> omega.com-
Is insertion loss at all an issue with TC stuff?
- S
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Date: 16 Mar 2007 19:35:21
From: wes
Subject: Re: Craftsman mini multimeter with K thermocouple
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On 16, 12:04 pm, "The Other Funk" <bob...@moondoggie.com > wrote:
> Finding the keyboard operational
> EskWI...@spamblock.panix.com entered:
>
>
>
>
>
> > In alt.coffee, The Other Funk <bob...@moondoggie.com> wrote:
> >> Finding the keyboard operational
> >> EskWI...@spamblock.panix.com entered:
>
> >>> In alt.coffee, Roger Shoaf <s...@nospamsyix.com> wrote:
>
> >>>> So let me see, if you were measuring water temp and you got a
> >>>> reading of 200F, +- 1.0% translates to +- 2 degrees F, but exactly
> >>>> what does +5 digits mean?
>
> >>> 200.00F
>
> >> No it means that the error at 200F can be +/- 7F
>
> > I don't understand that. Are you certain?
>From the manual:
"Accuracy specifications consist of two elements:
(% reading) - this is the accuracy of the measurement circuit
(+ digits) - this is the accuracy of the analog to digital converter"
>
> 20+ years calibrating test equipment including several years at Fluke. 7 of
> those years at AT&T Bell Labs.
> Digital meter specs in the form of +/- % reading + digits should be written
> as +/-(% reading +/- displayed digits) I have never seen specs given as A/D
> error for a DMM.
> Bob
>
> --
> --
> Coffee worth staying up for - NY Timeswww.moondoggiecoffee.com- Hide quoted text -
>
> - Show quoted text -
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Date: 16 Mar 2007 15:29:16
From: daveb
Subject: Re: Craftsman mini multimeter with K thermocouple
|
On 16, 2:56 pm, EskWI...@spamblock.panix.com wrote:
> In alt.coffee, The Other Funk <bob...@moondoggie.com> wrote:
>
> > 20+ years calibrating test equipment including several years at Fluke. =
7 of
> > those years at AT&T Bell Labs.
> > Digital meter specs in the form of +/- % reading + digits should be wri=
tten
> > as +/-(% reading +/- displayed digits) I have never seen specs given as=
A/D
> > error for a DMM.
>
> Cool. And very interestng.
>
> What accounts for the loose specs in cheap digital equipment (I am
> assuming that +/-n%+5 is not SOTA)? Is it some sort of repeated rounding
> error?
>
> --
> The whole problem with the world is that fools and fanatics are always so
> certain of themselves, but wiser people so full of doubts.
> -- Bertrand Russel
Here are the specs for a good thermometer: Fluke 51 series II
Temperature accuracy
Above -100 =B0C: J, K, T, E, and N-type: =B1[0.05% + 0.3=B0C]*
R and S-type: =B1[0.05% + 0.4=B0C]*
Below -100 =B0C: J, K, E, and N-types: =B1[0.20% + 0.3=B0C]*
T-type: =B1[0.50% + 0.3=B0C]
Temperature
J-type: -210 =B0C to 1200 =B0C
K-type: -200 =B0C to 1372 =B0C
T-type: -250 =B0C to 400 =B0C
E-type: -150 =B0C to 1000 =B0C
N-type: -200 =B0C to 1300 =B0C *
R and S-type: 0 =B0C to 1767 =B0C *
Temperature scale
ITS-90
Applicable standards
NIST-175
but then, it is $200.00
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Date: 16 Mar 2007 15:24:51
From: daveb
Subject: Re: Craftsman mini multimeter with K thermocouple
|
On 16, 6:09 pm, "rasqual" <scott.qua...@gmail.com > wrote:
> On 16, 5:02 pm, "daveb" <davebobbl...@gmail.com> wrote:
>
>
>
> > On 16, 4:23 pm, "J. Clarke" <jclarke.use...@cox.net> wrote:
>
> > > Miss Penny wrote:
> > > > On 16, 2:56 pm, EskWI...@spamblock.panix.com wrote:
> > > >> In alt.coffee, The Other Funk <bob...@moondoggie.com> wrote:
>
> > > >>> 20+ years calibrating test equipment including several years at
> > > >>> Fluke. 7 of those years at AT&T Bell Labs.
> > > >>> Digital meter specs in the form of +/- % reading + digits should be
> > > >>> written as +/-(% reading +/- displayed digits) I have never seen
> > > >>> specs given as A/D error for a DMM.
>
> > > >> Cool. And very interestng.
>
> > > >> What accounts for the loose specs in cheap digital equipment (I am
> > > >> assuming that +/-n%+5 is not SOTA)? Is it some sort of repeated
> > > >> rounding error?
>
> > > > what do you want for $10.00 ?
>
> > > > accuracy?
>
> > > I figure for 10 bucks how bad can it be? Certainly can't be any worse
> > > than the same money spent on coffee at Starbies.
>
> > LOL!
> > ----------------------
> > well, I rushed out and got one, and it works, and for $10 -- why not
> > indeed?
>
> OK, so if I have a TC already that has a mini-connector for
> thermocouples, how am I supposed to adapt it to the plug in the meter?
>
> Anyone have any sources for such non-standard thermocouple plugs that
> can be easily connected to TC wire?
>
> - S
omega.com
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Date: 16 Mar 2007 15:13:26
From: rasqual
Subject: Re: Craftsman mini multimeter with K thermocouple
|
On 16, 5:09 pm, "rasqual" <scott.qua...@gmail.com > wrote:
> OK, so if I have a TC already that has a mini-connector for
> thermocouples, how am I supposed to adapt it to the plug in the meter?
Argh. The jack in the meter.
- S
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Date: 16 Mar 2007 15:09:57
From: rasqual
Subject: Re: Craftsman mini multimeter with K thermocouple
|
On 16, 5:02 pm, "daveb" <davebobbl...@gmail.com > wrote:
> On 16, 4:23 pm, "J. Clarke" <jclarke.use...@cox.net> wrote:
>
>
>
>
>
> > Miss Penny wrote:
> > > On 16, 2:56 pm, EskWI...@spamblock.panix.com wrote:
> > >> In alt.coffee, The Other Funk <bob...@moondoggie.com> wrote:
>
> > >>> 20+ years calibrating test equipment including several years at
> > >>> Fluke. 7 of those years at AT&T Bell Labs.
> > >>> Digital meter specs in the form of +/- % reading + digits should be
> > >>> written as +/-(% reading +/- displayed digits) I have never seen
> > >>> specs given as A/D error for a DMM.
>
> > >> Cool. And very interestng.
>
> > >> What accounts for the loose specs in cheap digital equipment (I am
> > >> assuming that +/-n%+5 is not SOTA)? Is it some sort of repeated
> > >> rounding error?
>
> > > what do you want for $10.00 ?
>
> > > accuracy?
>
> > I figure for 10 bucks how bad can it be? Certainly can't be any worse
> > than the same money spent on coffee at Starbies.
>
> LOL!
> ----------------------
> well, I rushed out and got one, and it works, and for $10 -- why not
> indeed?
OK, so if I have a TC already that has a mini-connector for
thermocouples, how am I supposed to adapt it to the plug in the meter?
Anyone have any sources for such non-standard thermocouple plugs that
can be easily connected to TC wire?
- S
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Date: 16 Mar 2007 15:02:37
From: daveb
Subject: Re: Craftsman mini multimeter with K thermocouple
|
On 16, 4:23 pm, "J. Clarke" <jclarke.use...@cox.net > wrote:
> Miss Penny wrote:
> > On 16, 2:56 pm, EskWI...@spamblock.panix.com wrote:
> >> In alt.coffee, The Other Funk <bob...@moondoggie.com> wrote:
>
> >>> 20+ years calibrating test equipment including several years at
> >>> Fluke. 7 of those years at AT&T Bell Labs.
> >>> Digital meter specs in the form of +/- % reading + digits should be
> >>> written as +/-(% reading +/- displayed digits) I have never seen
> >>> specs given as A/D error for a DMM.
>
> >> Cool. And very interestng.
>
> >> What accounts for the loose specs in cheap digital equipment (I am
> >> assuming that +/-n%+5 is not SOTA)? Is it some sort of repeated
> >> rounding error?
>
> > what do you want for $10.00 ?
>
> > accuracy?
>
> I figure for 10 bucks how bad can it be? Certainly can't be any worse
> than the same money spent on coffee at Starbies.
LOL!
----------------------
well, I rushed out and got one, and it works, and for $10 -- why not
indeed?
dave
> --
> --
> --John
>
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Date: 16 Mar 2007 12:51:31
From: Miss Penny
Subject: Re: Craftsman mini multimeter with K thermocouple
|
On 16, 2:56 pm, EskWI...@spamblock.panix.com wrote:
> In alt.coffee, The Other Funk <bob...@moondoggie.com> wrote:
>
> > 20+ years calibrating test equipment including several years at Fluke. 7 of
> > those years at AT&T Bell Labs.
> > Digital meter specs in the form of +/- % reading + digits should be written
> > as +/-(% reading +/- displayed digits) I have never seen specs given as A/D
> > error for a DMM.
>
> Cool. And very interestng.
>
> What accounts for the loose specs in cheap digital equipment (I am
> assuming that +/-n%+5 is not SOTA)? Is it some sort of repeated rounding
> error?
>
what do you want for $10.00 ?
accuracy?
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Date: 16 Mar 2007 16:23:24
From: J. Clarke
Subject: Re: Craftsman mini multimeter with K thermocouple
|
Miss Penny wrote:
> On 16, 2:56 pm, EskWI...@spamblock.panix.com wrote:
>> In alt.coffee, The Other Funk <bob...@moondoggie.com> wrote:
>>
>>> 20+ years calibrating test equipment including several years at
>>> Fluke. 7 of those years at AT&T Bell Labs.
>>> Digital meter specs in the form of +/- % reading + digits should be
>>> written as +/-(% reading +/- displayed digits) I have never seen
>>> specs given as A/D error for a DMM.
>>
>> Cool. And very interestng.
>>
>> What accounts for the loose specs in cheap digital equipment (I am
>> assuming that +/-n%+5 is not SOTA)? Is it some sort of repeated
>> rounding error?
>>
>
>
> what do you want for $10.00 ?
>
> accuracy?
I figure for 10 bucks how bad can it be? Certainly can't be any worse
than the same money spent on coffee at Starbies.
--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
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Date: 16 Mar 2007 08:33:17
From: daveb
Subject: Re: Craftsman mini multimeter with K thermocouple
|
>
> Multimeters have become disposables.
ACCURATE ones are not.
dave
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Date: 16 Mar 2007 05:24:51
From: MOJO
Subject: Re: Craftsman mini multimeter with K thermocouple
|
On 15, 11:40 pm, jggall01 <jggal...@yahoo.com > wrote:
> On Thu, 15 2007 23:06:11 GMT, "The Other Funk"
>
> <bob...@moondoggie.com> wrote:
> >+/- 5 digits means that the last digit could be high or low by 5. In your
> >example, a three digit display measuring 200F could read 193 to 207. A three
> >and a half dsisplay (00.0 - 199.9) could read 199.3F to overload.
>
> The +/- 5 digits is for C scale. Spec's say the F scale is +/- 9
> digits.
>
> Jim
Well this device obviously does not have a 9 digit display. Everything
shown indicates it has a four digit display. I believe the correct
interpretation of the tolerance (per the spec sheet) for a Fahrenheit
reading in the range of 60 to 750 degrees F is +-(1% reading + 9
digits).
My understanding of this specification is as follows: For 200 degrees
F this is represented as 200.0 x .0100 = 2.000 Scientific notation
could be used to clarify the significant digits but if you stay with
the displayed figure, and make sure that you maintain accuracy
throughout then the calculation for the tolerance would be accurate.
It is not done yet though. Place the +9 value in the position of the
least significant digit and add it to the initial calculated tolerance
making the actual tolerance +-(2.000+ 0.009) = +-2.009 =
1.0045% and going back to four sig digs 1.005% makes the actual range
between 197.9(9) deg. F and 202.0(1) deg. F or with careful rounding
198.0 to 202.0.
For a Celsius or Centigrade reading in the same range a tolerance is
given a +-(1% reading +5 digits). It is a little different. Taking the
reading of 93.30 degrees the tolerance is +- (.9330 + .0005) = +-(.
9335) = +- 1.001 % making the actual range 92.37 deg. C to 94.23 deg.
C.
A smidge tighter for the Centigrade scale.
That's how I see it.
It is definitely close enough for me. I ordered one.
MOJO
(Roasters Mate Second Class)
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Date: 14 Mar 2007 22:31:09
From: Bwisit
Subject: Re: Craftsman mini multimeter with K thermocouple
|
Bought one of these when they were still $19.99, which irks me since
it wasn't too long ago, but long enough that I can't get a refund. I
like it, works well. But be warned, there's blue tape that is stuck
to the end of the thermocouple, won't survive anything above 400F.
Mine melted in the beans I was roasting. Oh well. Still tasted good.
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Date: 15 Mar 2007 14:28:13
From: yoma
Subject: Re: Craftsman mini multimeter with K thermocouple
|
Randy G. wrote:
> Craftsman Digital Mini Multimeter
>> http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=TOOL&cat=Electrical+Shop&subcat=Multi-Meters%2C+Testers+%26+Accessories&pid=03482345000
> (http://tinyurl.com/3byoa7)
> Comes with type K thermocouple
> $9.99 and free in store pickup
>
> No experience with it- just thought about folks looking for a cheap
> thermometer, etc.
Specs. from the online manual:
17C to 400C, 60 to 750F, +/-(1.0% reading + 5 digits)
Pretty impressive.
Just an intergated-circuit (AD595) alone would cost more than the whole
setup above.
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Date: 15 Mar 2007 10:10:50
From: Roger Shoaf
Subject: Re: Craftsman mini multimeter with K thermocouple
|
"yoma" <yoma@yoma.net.au > wrote in message
news:45f8bd4d$0$8368$5a62ac22@per-qv1-newsreader-01.iinet.net.au...
> Specs. from the online manual:
>
> 17C to 400C, 60 to 750F, +/-(1.0% reading + 5 digits)
>
> Pretty impressive.
>
> Just an intergated-circuit (AD595) alone would cost more than the whole
> setup above.
So let me see, if you were measuring water temp and you got a reading of
200F, +- 1.0% translates to +- 2 degrees F, but exactly what does +5 digits
mean? Also how fast does the probe talk to the meter? In other words, does
the reading indicate what the probe is seeing now? Or what it is seeing 20
seconds ago?
--
Roger Shoaf
About the time I had mastered getting the toothpaste back in the tube, then
they come up with this striped stuff.
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Date: 15 Mar 2007 23:06:11
From: The Other Funk
Subject: Re: Craftsman mini multimeter with K thermocouple
|
Finding the keyboard operational
Roger Shoaf entered:
> "yoma" <yoma@yoma.net.au> wrote in message
> news:45f8bd4d$0$8368$5a62ac22@per-qv1-newsreader-01.iinet.net.au...
>
>> Specs. from the online manual:
>>
>> 17C to 400C, 60 to 750F, +/-(1.0% reading + 5 digits)
>>
>> Pretty impressive.
>>
>> Just an intergated-circuit (AD595) alone would cost more than the
>> whole setup above.
>
>
> So let me see, if you were measuring water temp and you got a reading
> of 200F, +- 1.0% translates to +- 2 degrees F, but exactly what does
> +5 digits mean? Also how fast does the probe talk to the meter? In
> other words, does the reading indicate what the probe is seeing now?
> Or what it is seeing 20 seconds ago?
+/- 5 digits means that the last digit could be high or low by 5. In your
example, a three digit display measuring 200F could read 193 to 207. A three
and a half dsisplay (00.0 - 199.9) could read 199.3F to overload.
Then you have to add in the thermocouple error which is the greater of 2.2C
or 0.75% of the reading. (info from http://www.omega.com/thermocouples.html)
Display updates are a function of thermal coupling of the probe to the
heated object, the thermal mass of the porbe and the A to D converter.
OTOH for $10.00 you really can't go wrong.
Bob
--
--
Coffee worth staying up for - NY Times
www.moondoggiecoffee.com
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Date: 15 Mar 2007 23:40:47
From: jggall01
Subject: Re: Craftsman mini multimeter with K thermocouple
|
On Thu, 15 2007 23:06:11 GMT, "The Other Funk"
<bobbie@moondoggie.com > wrote:
>+/- 5 digits means that the last digit could be high or low by 5. In your
>example, a three digit display measuring 200F could read 193 to 207. A three
>and a half dsisplay (00.0 - 199.9) could read 199.3F to overload.
The +/- 5 digits is for C scale. Spec's say the F scale is +/- 9
digits.
Jim
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Date: 16 Mar 2007 07:24:57
From: yoma
Subject: Re: Craftsman mini multimeter with K thermocouple
|
Roger Shoaf wrote:
> "yoma" <yoma@yoma.net.au> wrote in message
> news:45f8bd4d$0$8368$5a62ac22@per-qv1-newsreader-01.iinet.net.au...
>
>> Specs. from the online manual:
>>
>> 17C to 400C, 60 to 750F, +/-(1.0% reading + 5 digits)
>>
>> Pretty impressive.
>>
>> Just an intergated-circuit (AD595) alone would cost more than the whole
>> setup above.
>
>
> So let me see, if you were measuring water temp and you got a reading of
> 200F, +- 1.0% translates to +- 2 degrees F, but exactly what does +5 digits
> mean? Also how fast does the probe talk to the meter? In other words, does
> the reading indicate what the probe is seeing now? Or what it is seeing 20
> seconds ago?
Thermocouples (TC's) are used because of their speed - they provide an
immediate voltage level depending on the temperature. If it's
encapsulated in a steel covering it will slow down - depending on encasing.
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| | | |
Date: 15 Mar 2007 20:18:48
From:
Subject: Re: Craftsman mini multimeter with K thermocouple
|
In alt.coffee, Roger Shoaf <shoaf@nospamsyix.com > wrote:
> So let me see, if you were measuring water temp and you got a reading of
> 200F, +- 1.0% translates to +- 2 degrees F, but exactly what does +5 digits
> mean?
200.00F
--
The whole problem with the world is that fools and fanatics are always so
certain of themselves, but wiser people so full of doubts.
-- Bertrand Russel
|
| | | | |
Date: 15 Mar 2007 23:07:53
From: The Other Funk
Subject: Re: Craftsman mini multimeter with K thermocouple
|
Finding the keyboard operational
EskWIRED@spamblock.panix.com entered:
> In alt.coffee, Roger Shoaf <shoaf@nospamsyix.com> wrote:
>
>> So let me see, if you were measuring water temp and you got a
>> reading of 200F, +- 1.0% translates to +- 2 degrees F, but exactly
>> what does +5 digits mean?
>
> 200.00F
No it means that the error at 200F can be +/- 7F
Bob
--
--
Coffee worth staying up for - NY Times
www.moondoggiecoffee.com
|
| | | | | |
Date: 16 Mar 2007 15:15:56
From:
Subject: Re: Craftsman mini multimeter with K thermocouple
|
In alt.coffee, The Other Funk <bobbie@moondoggie.com > wrote:
> Finding the keyboard operational
> EskWIRED@spamblock.panix.com entered:
> > In alt.coffee, Roger Shoaf <shoaf@nospamsyix.com> wrote:
> >
> >> So let me see, if you were measuring water temp and you got a
> >> reading of 200F, +- 1.0% translates to +- 2 degrees F, but exactly
> >> what does +5 digits mean?
> >
> > 200.00F
> No it means that the error at 200F can be +/- 7F
I don't understand that. Are you certain?
--
The whole problem with the world is that fools and fanatics are always so
certain of themselves, but wiser people so full of doubts.
-- Bertrand Russel
|
| | | | | | |
Date: 16 Mar 2007 17:04:04
From: The Other Funk
Subject: Re: Craftsman mini multimeter with K thermocouple
|
Finding the keyboard operational
EskWIRED@spamblock.panix.com entered:
> In alt.coffee, The Other Funk <bobbie@moondoggie.com> wrote:
>> Finding the keyboard operational
>> EskWIRED@spamblock.panix.com entered:
>
>>> In alt.coffee, Roger Shoaf <shoaf@nospamsyix.com> wrote:
>>>
>>>> So let me see, if you were measuring water temp and you got a
>>>> reading of 200F, +- 1.0% translates to +- 2 degrees F, but exactly
>>>> what does +5 digits mean?
>>>
>>> 200.00F
>
>> No it means that the error at 200F can be +/- 7F
>
>
> I don't understand that. Are you certain?
20+ years calibrating test equipment including several years at Fluke. 7 of
those years at AT&T Bell Labs.
Digital meter specs in the form of +/- % reading + digits should be written
as +/-(% reading +/- displayed digits) I have never seen specs given as A/D
error for a DMM.
Bob
--
--
Coffee worth staying up for - NY Times
www.moondoggiecoffee.com
|
| | | | | | | |
Date: 16 Mar 2007 23:30:08
From: pltrgyst
Subject: Re: Craftsman mini multimeter with K thermocouple
|
On Fri, 16 2007 17:04:04 GMT, "The Other Funk" <bobbie@moondoggie.com >
wrote:
>>>>> So let me see, if you were measuring water temp and you got a
>>>>> reading of 200F, +- 1.0% translates to +- 2 degrees F, but exactly
>>>>> what does +5 digits mean?
>>>>
>>>> 200.00F
>>
>>> No it means that the error at 200F can be +/- 7F
>>
>> I don't understand that. Are you certain?
>
>20+ years calibrating test equipment including several years at Fluke. 7 of
>those years at AT&T Bell Labs.
Except that in this case, the above is wrong. This display is commonly called a
3.5 digit display -- Sears describes it as a "2,000 count". This means the
display runs from 0 to 1999. The manual is available in PDF at the Sears site.
Such a display *could* display in tenths of a degree up to 199.9, but we don't
know for sure that it does -- it could well display only in whole degrees. For
anything over 199.9, it can *only* display in whole degrees -- and those "+5"
digits can only represent whole degrees of error.
I have two on order as well, so we'll see soon. And remember, those figures
above don't include thermocouple accuracy or repeatability. So this is not
exactly a lab grade instrument. It's probably no more accurate than a Radio
Shack dual-temp. indoor/outdoor thermometer.
-- Larry (10 years at RCA's Sarnoff Research Center, 5 at WE Engineering
Research Center, 4 yrs. at Bell Labs Holmdel, 5 at MITRE, now 20 at the US
Patent Office. Is someone compiling CVs? 8;) )
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Date: 17 Mar 2007 18:15:39
From: The Other Funk
Subject: Re: Craftsman mini multimeter with K thermocouple
|
Finding the keyboard operational
pltrgyst entered:
> On Fri, 16 2007 17:04:04 GMT, "The Other Funk"
> <bobbie@moondoggie.com> wrote:
>
>>>>>> So let me see, if you were measuring water temp and you got a
>>>>>> reading of 200F, +- 1.0% translates to +- 2 degrees F, but
>>>>>> exactly what does +5 digits mean?
>>>>>
>>>>> 200.00F
>>>
>>>> No it means that the error at 200F can be +/- 7F
>>>
>>> I don't understand that. Are you certain?
>>
>> 20+ years calibrating test equipment including several years at
>> Fluke. 7 of those years at AT&T Bell Labs.
>
> Except that in this case, the above is wrong. This display is
> commonly called a
> 3.5 digit display -- Sears describes it as a "2,000 count". This
> means the display runs from 0 to 1999. The manual is available in PDF
> at the Sears site.
>
> Such a display *could* display in tenths of a degree up to 199.9, but
> we don't know for sure that it does -- it could well display only in
> whole degrees. For anything over 199.9, it can *only* display in
> whole degrees -- and those "+5" digits can only represent whole
> degrees of error.
>
> I have two on order as well, so we'll see soon. And remember, those
> figures above don't include thermocouple accuracy or repeatability.
> So this is not exactly a lab grade instrument. It's probably no more
> accurate than a Radio Shack dual-temp. indoor/outdoor thermometer.
>
> -- Larry (10 years at RCA's Sarnoff Research Center, 5 at WE
> Engineering Research Center, 4 yrs. at Bell Labs Holmdel, 5 at MITRE,
> now 20 at the US Patent Office. Is someone compiling CVs? 8;) )
That will teach me to RTFM before saying anything.
Well, I've been wrong before and will be again.
BTW I was at RCA Solid State Somerville in the late 70s. Small world.
Bob
--
--
Coffee worth staying up for - NY Times
www.moondoggiecoffee.com
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Date: 18 Mar 2007 01:15:40
From: pltrgyst
Subject: Re: Craftsman mini multimeter with K thermocouple
|
On Sat, 17 2007 18:15:39 GMT, "The Other Funk" <bobbie@moondoggie.com >
wrote:
>> -- Larry (10 years at RCA's Sarnoff Research Center....
>
>BTW I was at RCA Solid State Somerville in the late 70s. Small world.
Greetings from Nipper!
Strange world, actually -- I grew up in Edison, lived around Princeton and in
Hopewell for so many years; made a lot of trips to RCA in Lancaster and out in
Indy, but I never visited RCA Somerville, right next door. 8;)
-- Larry
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Date: 18 Mar 2007 11:37:36
From: The Other Funk
Subject: Re: Craftsman mini multimeter with K thermocouple
|
Finding the keyboard operational
pltrgyst entered:
> On Sat, 17 2007 18:15:39 GMT, "The Other Funk"
> <bobbie@moondoggie.com> wrote:
>
>
>>> -- Larry (10 years at RCA's Sarnoff Research Center....
>>
>> BTW I was at RCA Solid State Somerville in the late 70s. Small world.
>
> Greetings from Nipper!
>
> Strange world, actually -- I grew up in Edison, lived around
> Princeton and in Hopewell for so many years; made a lot of trips to
> RCA in Lancaster and out in Indy, but I never visited RCA Somerville,
> right next door. 8;)
>
> -- Larry
And the world keeps shrinking! I grew up in Edison myself! Washington Park
area. The south end. About half a mile from Edison High school. Spent about
12 years on the First Aid squad.
Bob
--
--
Coffee worth staying up for - NY Times
www.moondoggiecoffee.com
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Date: 18 Mar 2007 12:16:07
From: pltrgyst
Subject: Re: Craftsman mini multimeter with K thermocouple
|
On Sun, 18 2007 11:37:36 GMT, "The Other Funk" <bobbie@moondoggie.com >
wrote:
>> Strange world, actually -- I grew up in Edison...
>
>And the world keeps shrinking! I grew up in Edison myself! Washington Park
>area. The south end. About half a mile from Edison High school. Spent about
>12 years on the First Aid squad.
Wow -- this is wierd. 8;)
Washington Park here too. 38 Colton Road, to be precise. That huge oak tree in
the back yard, visible in satellite photos? I planted it in 1951 when we moved
there.
My family move to North brunswick in 1965, so I never really lived in Edison
after high school (Edison, '64). I was last up for our 40th reunion -- took my
wife to have a Tastee sub and some goodies from the old bakery on Rt. 27 near
The Pines.
What street did you live on?
Wait a minute -- Funk? Any relation to Fred Funk?
-- Larry
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Date: 18 Mar 2007 17:13:50
From: The Other Funk
Subject: Re: Craftsman mini multimeter with K thermocouple
|
Finding the keyboard operational
pltrgyst entered:
> On Sun, 18 2007 11:37:36 GMT, "The Other Funk"
> <bobbie@moondoggie.com> wrote:
>
>>> Strange world, actually -- I grew up in Edison...
>>
>> And the world keeps shrinking! I grew up in Edison myself!
>> Washington Park area. The south end. About half a mile from Edison
>> High school. Spent about 12 years on the First Aid squad.
>
> Wow -- this is wierd. 8;)
>
> Washington Park here too. 38 Colton Road, to be precise. That huge
> oak tree in the back yard, visible in satellite photos? I planted it
> in 1951 when we moved there.
>
> My family move to North brunswick in 1965, so I never really lived in
> Edison after high school (Edison, '64). I was last up for our 40th
> reunion -- took my wife to have a Tastee sub and some goodies from
> the old bakery on Rt. 27 near The Pines.
>
> What street did you live on?
>
> Wait a minute -- Funk? Any relation to Fred Funk?
>
> -- Larry
31 Baldwin Rd. for me.
Fred Jr. is my older brother and you might remember my older sister Joan
too. Class of 64 works out about right for Fred.
A few years ago I had to have some surgery and as soon as the Doctor allowed
me solid food, I sent my wife down to Tastee for a number 7.
Email is Bob at the website below..
Bob
--
--
Coffee worth staying up for - NY Times
www.moondoggiecoffee.com
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Date: 17 Mar 2007 08:51:38
From: Ian Smith
Subject: Re: Craftsman mini multimeter with K thermocouple
|
On Fri, 16 2007 23:30:08 -0400, pltrgyst <pltrgyst@spamlessxhost.org > wrote:
> On Fri, 16 2007 17:04:04 GMT, "The Other Funk" <bobbie@moondoggie.com>
> wrote:
>
> >>> No it means that the error at 200F can be +/- 7F
> >>
> >> I don't understand that. Are you certain?
> >
> >20+ years calibrating test equipment including several years at
> >Fluke. 7 of those years at AT&T Bell Labs.
>
> Except that in this case, the above is wrong. This display is
> commonly called a 3.5 digit display -- Sears describes it as a
> "2,000 count". This means the display runs from 0 to 1999. The
> manual is available in PDF at the Sears site.
>
> Such a display *could* display in tenths of a degree up to 199.9,
> but we don't know for sure that it does -- it could well display
> only in whole degrees. For anything over 199.9, it can *only*
> display in whole degrees -- and those "+5" digits can only
> represent whole degrees of error.
So, for 200F it can only display whole degrees, so the error would be
7F, so in what way is the statement wrong?
regards, Ian SMith
--
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Date: 17 Mar 2007 11:33:40
From: pltrgyst
Subject: Re: Craftsman mini multimeter with K thermocouple
|
On 17 2007 08:51:38 GMT, Ian Smith <ian@astounding.org.uk > wrote:
>>So, for 200F it can only display whole degrees, so the error would be
>7F, so in what way is the statement wrong?
Not your statement -- the example to which you referred, which was "200.00F".
-- Larry
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Date: 17 Mar 2007 16:04:21
From: Ian Smith
Subject: Re: Craftsman mini multimeter with K thermocouple
|
On Sat, 17 2007, pltrgyst <pltrgyst@spamlessxhost.org > wrote:
> On 17 2007 08:51:38 GMT, Ian Smith <ian@astounding.org.uk> wrote:
>
>> So, for 200F it can only display whole degrees, so the error would
>> be 7F, so in what way is the statement wrong?
>
> Not your statement -- the example to which you referred, which was
> "200.00F".
1: That wasn't my statement. Mothing was my statement. I did not
refer. I had not previously posted in the thread.
2: It's a bit odd to say "no that's wrong" when what you mean was
wrong was something someone said days ago way up a chain of quotes.
regards, Ian SMith
--
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Date: 16 Mar 2007 18:56:03
From:
Subject: Re: Craftsman mini multimeter with K thermocouple
|
In alt.coffee, The Other Funk <bobbie@moondoggie.com > wrote:
> 20+ years calibrating test equipment including several years at Fluke. 7 of
> those years at AT&T Bell Labs.
> Digital meter specs in the form of +/- % reading + digits should be written
> as +/-(% reading +/- displayed digits) I have never seen specs given as A/D
> error for a DMM.
Cool. And very interestng.
What accounts for the loose specs in cheap digital equipment (I am
assuming that +/-n%+5 is not SOTA)? Is it some sort of repeated rounding
error?
--
The whole problem with the world is that fools and fanatics are always so
certain of themselves, but wiser people so full of doubts.
-- Bertrand Russel
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Date: 17 Mar 2007 02:38:15
From: The Other Funk
Subject: Re: Craftsman mini multimeter with K thermocouple
|
Finding the keyboard operational
EskWIRED@spamblock.panix.com entered:
> In alt.coffee, The Other Funk <bobbie@moondoggie.com> wrote:
>
>> 20+ years calibrating test equipment including several years at
>> Fluke. 7 of those years at AT&T Bell Labs.
>> Digital meter specs in the form of +/- % reading + digits should be
>> written as +/-(% reading +/- displayed digits) I have never seen
>> specs given as A/D error for a DMM.
>
> Cool. And very interestng.
>
> What accounts for the loose specs in cheap digital equipment (I am
> assuming that +/-n%+5 is not SOTA)? Is it some sort of repeated
> rounding error?
I remember one digital Volt meter with a 8 digit display with a spec of n%
+/- 25 for one range! This was SOTA in the 80s. We called it a spec that
you could drive a truck thru.
Specs should be set by careful analysis of a whole lot of things but
sometimes it seems that they are set by what the thing will read a year from
now.
For a 10 buck, 3 1/2 digit multimeter 2% +/- 5 is pretty good. At 100 bucks
I'd expect < 1%.
Bob
--
--
Coffee worth staying up for - NY Times
www.moondoggiecoffee.com
|
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Date: 15 Mar 2007 20:57:04
From: pltrgyst
Subject: Re: Craftsman mini multimeter with K thermocouple
|
On Thu, 15 2007 23:07:53 GMT, "The Other Funk" <bobbie@moondoggie.com >
wrote:
>Finding the keyboard operational
> EskWIRED@spamblock.panix.com entered:
>
>> In alt.coffee, Roger Shoaf <shoaf@nospamsyix.com> wrote:
>>
>>> So let me see, if you were measuring water temp and you got a
>>> reading of 200F, +- 1.0% translates to +- 2 degrees F, but exactly
>>> what does +5 digits mean?
>>
>> 200.00F
>
>No it means that the error at 200F can be +/- 7F
No, it's the potential error in the A/D converter. It means with a five digit
display, this particular error can be as much as 5 numbers in the low-order
digit (i.e., + .05 degrees).
-- Larry
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Date: 15 Mar 2007 13:44:11
From: sprsso
Subject: Re: Craftsman mini multimeter with K thermocouple
|
Thanks for the heads up. Picking mine up in an hour. That'll only be 6
digital and 3 analog therms for me. And I'll let you know how fast a
$10 digital therm talks to itself. But it'll cost you $25.00....al
On Thu, 15 2007 10:10:50 -0700, "Roger Shoaf"
<shoaf@nospamsyix.com > wrote:
>
>"yoma" <yoma@yoma.net.au> wrote in message
>news:45f8bd4d$0$8368$5a62ac22@per-qv1-newsreader-01.iinet.net.au...
>
>> Specs. from the online manual:
>>
>> 17C to 400C, 60 to 750F, +/-(1.0% reading + 5 digits)
>>
>> Pretty impressive.
>>
>> Just an intergated-circuit (AD595) alone would cost more than the whole
>> setup above.
>
>
>So let me see, if you were measuring water temp and you got a reading of
>200F, +- 1.0% translates to +- 2 degrees F, but exactly what does +5 digits
>mean? Also how fast does the probe talk to the meter? In other words, does
>the reading indicate what the probe is seeing now? Or what it is seeing 20
>seconds ago?
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Date: 15 Mar 2007 11:47:28
From: Roger Shoaf
Subject: Re: Craftsman mini multimeter with K thermocouple
|
"sprsso" <acritzer@cfl.rr.com > wrote in message
news:7f1jv2latqk5v9h22e3rrhr6ic5ov2gqeo@4ax.com...
> Thanks for the heads up. Picking mine up in an hour. That'll only be 6
> digital and 3 analog therms for me. And I'll let you know how fast a
> $10 digital therm talks to itself. But it'll cost you $25.00....al
>
OK I'll owe you. I would much rather owe you than beat you out of it.: >)
On the serious side, an inaccurate measurement would not be bad as long as
it was consistent in it's performance. The down side would be if you were 2
degrees high on one measurement, and 2 degrees low on the next.
--
Roger Shoaf
About the time I had mastered getting the toothpaste back in the tube, then
they come up with this striped stuff.
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Date: 16 Mar 2007 07:51:14
From: yoma
Subject: Re: Craftsman mini multimeter with K thermocouple
|
Roger Shoaf wrote:
>
> On the serious side, an inaccurate measurement would not be bad as long as
> it was consistent in it's performance. The down side would be if you were 2
> degrees high on one measurement, and 2 degrees low on the next.
Note the spec: '+/- 1.0% reading'
Take that as meaning it's AD (analog/digital) converter is 10bit.
It can convert a 'analog' reading from the thermocouple to 1% accuracy.
The accuracy/stability/quality of the value provided by the thermocouple
IS an entirely different matter.
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Date: 16 Mar 2007 11:32:32
From: Roger Shoaf
Subject: Re: Craftsman mini multimeter with K thermocouple
|
"yoma" <yoma@yoma.net.au > wrote in message
news:45f9b1c2$0$8358$5a62ac22@per-qv1-newsreader-01.iinet.net.au...
> Roger Shoaf wrote:
> >
> > On the serious side, an inaccurate measurement would not be bad as long
as
> > it was consistent in it's performance. The down side would be if you
were 2
> > degrees high on one measurement, and 2 degrees low on the next.
>
> Note the spec: '+/- 1.0% reading'
>
> Take that as meaning it's AD (analog/digital) converter is 10bit.
> It can convert a 'analog' reading from the thermocouple to 1% accuracy.
>
> The accuracy/stability/quality of the value provided by the thermocouple
> IS an entirely different matter.
But what does the + 5 digits translate to? Whatever the inaccuracy is, it
appears that that is in addition to the 1%. Of course this wouldn't matter
much if the repeatability was acceptable.
--
Roger Shoaf
About the time I had mastered getting the toothpaste back in the tube, then
they come up with this striped stuff.
|
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Date: 17 Mar 2007 02:28:36
From: The Other Funk
Subject: Re: Craftsman mini multimeter with K thermocouple
|
Finding the keyboard operational
Roger Shoaf entered:
> "yoma" <yoma@yoma.net.au> wrote in message
> news:45f9b1c2$0$8358$5a62ac22@per-qv1-newsreader-01.iinet.net.au...
>> Roger Shoaf wrote:
>>>
>>> On the serious side, an inaccurate measurement would not be bad as
>>> long as it was consistent in it's performance. The down side would
>>> be if you were 2 degrees high on one measurement, and 2 degrees low
>>> on the next.
>>
>> Note the spec: '+/- 1.0% reading'
>>
>> Take that as meaning it's AD (analog/digital) converter is 10bit.
>> It can convert a 'analog' reading from the thermocouple to 1%
>> accuracy.
>>
>> The accuracy/stability/quality of the value provided by the
>> thermocouple IS an entirely different matter.
>
> But what does the + 5 digits translate to? Whatever the inaccuracy
> is, it appears that that is in addition to the 1%. Of course this
> wouldn't matter much if the repeatability was acceptable.
Repeatability should be OK. I would guess +/- 1 F long term. The easiest
way to check your digital thermometer at home is to make up a glass of half
ice chips and half water. That will get you close enough to 32F. Boil up
some water for 212F or whatever water boils at for your altitude. A straight
line graph will be close enough,
Bob
--
--
Coffee worth staying up for - NY Times
www.moondoggiecoffee.com
|
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Date: 15 Mar 2007 07:28:09
From: D. Ross
Subject: Re: Craftsman mini multimeter with K thermocouple
|
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Date: 14 Mar 2007 21:00:32
From: jim schulman
Subject: Re: Craftsman mini multimeter with K thermocouple
|
On Wed, 14 2007 11:36:36 -0700, Randy G. <frcn@DESPAMMOcncnet.com >
wrote:
> Craftsman Digital Mini Multimeter
>>http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=TOOL&cat=Electrical+Shop&subcat=Multi-Meters%2C+Testers+%26+Accessories&pid=03482345000
>(http://tinyurl.com/3byoa7)
>Comes with type K thermocouple
>$9.99 and free in store pickup
>
>No experience with it- just thought about folks looking for a cheap
>thermometer, etc.
Cool! a better looking successor to the awol techbuys 9.99
thermocouple/MM
|
| |
Date: 14 Mar 2007 20:15:01
From: Marshall
Subject: Re: Craftsman mini multimeter with K thermocouple
|
On Wed, 14 2007 11:36:36 -0700, Randy G. <frcn@DESPAMMOcncnet.com >
wrote:
> Craftsman Digital Mini Multimeter
>>http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=TOOL&cat=Electrical+Shop&subcat=Multi-Meters%2C+Testers+%26+Accessories&pid=03482345000
>(http://tinyurl.com/3byoa7)
>Comes with type K thermocouple
>$9.99 and free in store pickup
>
>No experience with it- just thought about folks looking for a cheap
>thermometer, etc.
>
>
> Randy "sorry, it's not free" G.
>http://www.EspressoMyEspresso.com
Just a warning that these are dandy little products (I have one). But
they will not work with a Scace thermofilter, which only connects to
type T thermocouples.
shall "let's harangue Greg some more about this"
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