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Author Power quality monitor -- cheap?
John E.

2007-02-21, 5:25 pm

I'm looking for the most economical means to monitor mains voltage for spikes
and other such disturbances over an unattended period of time.

I see that there are 2 categories of monitoring and logging equipment: event
loggers and samplers. The former requires the setting of thresholds and will
record any event that exceeds these; the latter simply samples the input at a
set interval.

I am looking for a device that records events.

I'd rather avoid the very expensive power quality monitors ($2000-plus
category). This reduces the list to DMMs with logging capability, which
includes the Fluke 189. (I'll add that if a data-download option exists, I
would prefer the ability to review data on the device rather than *require*
that it be downloaded -- I want to be able to, at a glance, confirm that a
power problem exists, and have the *option* to download the data for detailed
examination if I wish.)

Any other suggestions to achieve my means would be greatly appreciated.

Thanks,
--
John English

Jan Panteltje

2007-02-21, 5:25 pm

On a sunny day (Wed, 21 Feb 2007 12:13:59 -0800) it happened John E.
<incognito@yahoo.com> wrote in
<0001HW.C201E807002FC230F01826C8@news.readfreenews.net>:

>I'm looking for the most economical means to monitor mains voltage for spikes
>and other such disturbances over an unattended period of time.



A simple idea:
Divide the main to .7V eff with 2 resistors.
Feed into PC soundcard line input.
Record a wave file at 8000 samples/second mono.
Bit harddisk space should last a long time.
When done enter recorded wave file in an audio editor, display waveform,
and look for peaks, etc....

**THE-RFI-EMI-GUY**

2007-02-21, 5:25 pm

Please! I hope you mean to have this buffered through an isolation
transformer!

Jan Panteltje wrote:

>On a sunny day (Wed, 21 Feb 2007 12:13:59 -0800) it happened John E.
><incognito@yahoo.com> wrote in
><0001HW.C201E807002FC230F01826C8@news.readfreenews.net>:
>
>
>
>
>
>A simple idea:
>Divide the main to .7V eff with 2 resistors.
>Feed into PC soundcard line input.
>Record a wave file at 8000 samples/second mono.
>Bit harddisk space should last a long time.
>When done enter recorded wave file in an audio editor, display waveform,
>and look for peaks, etc....
>
>
>


--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P



**THE-RFI-EMI-GUY**

2007-02-21, 5:25 pm

Otherwise its a good idea except for the safety issue. Get a step down
transformer from "mains" to 6 or 12 volts so that you dont fry anything.

Jan Panteltje wrote:

>On a sunny day (Wed, 21 Feb 2007 12:13:59 -0800) it happened John E.
><incognito@yahoo.com> wrote in
><0001HW.C201E807002FC230F01826C8@news.readfreenews.net>:
>
>
>
>
>
>A simple idea:
>Divide the main to .7V eff with 2 resistors.
>Feed into PC soundcard line input.
>Record a wave file at 8000 samples/second mono.
>Bit harddisk space should last a long time.
>When done enter recorded wave file in an audio editor, display waveform,
>and look for peaks, etc....
>
>
>


--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P



gfretwell@aol.com

2007-02-21, 5:25 pm

On Wed, 21 Feb 2007 20:19:14 GMT, Jan Panteltje
<pNaonStpealmtje@yahoo.com> wrote:

>A simple idea:
>Divide the main to .7V eff with 2 resistors.
>Feed into PC soundcard line input.
>Record a wave file at 8000 samples/second mono.
>Bit harddisk space should last a long time.
>When done enter recorded wave file in an audio editor, display waveform,
>and look for peaks, etc....



Interesting concept. I bet if you used a compressed format like MP3
the disk would last for a really long time. Any machine in the faster
P1 or P11 class can compress on the fly.
Homer J Simpson

2007-02-21, 5:25 pm


"Jan Panteltje" <pNaonStpealmtje@yahoo.com> wrote in message
news:eri9ga$6ij$1@news.datemas.de...

>
> A simple idea:
> Divide the main to .7V eff with 2 resistors.


NO! At least run the AC through a 120 - 12 volt step-down transformer first.
Hooking AC directly to the input of a computer is a seriously bad idea.


--
..

--
..
..
..
..
..
..
..
..

--


Ben Miller

2007-02-21, 5:25 pm

"John E." <incognito@yahoo.com> wrote in message
news:0001HW.C201E807002FC230F01826C8@news.readfreenews.net...
> I'm looking for the most economical means to monitor mains voltage for
> spikes
> and other such disturbances over an unattended period of time.
>
> I see that there are 2 categories of monitoring and logging equipment:
> event
> loggers and samplers. The former requires the setting of thresholds and
> will
> record any event that exceeds these; the latter simply samples the input
> at a
> set interval.
>
> I am looking for a device that records events.
>
> I'd rather avoid the very expensive power quality monitors ($2000-plus
> category). This reduces the list to DMMs with logging capability, which
> includes the Fluke 189. (I'll add that if a data-download option exists, I
> would prefer the ability to review data on the device rather than
> *require*
> that it be downloaded -- I want to be able to, at a glance, confirm that a
> power problem exists, and have the *option* to download the data for
> detailed
> examination if I wish.)
>
> Any other suggestions to achieve my means would be greatly appreciated.
>
> Thanks,
> --
> John English
>


I don't know of an inexpensive commercial solution for catching fast
transients and harmonic distortion. The Fluke 189 will capture sags and
surges if you set the log rate fast enough, and it will capture 250uS
transients, although I don't recall how much it can do simultaneously. I
have one, but I don't use it for that purpose. It stores 100 readings, and
does have a com port for uploading data.

You might also consider a BMI 4800, generally available on eBay pretty
cheap. It has a built-in printer which will print actual waveforms, and also
had a communication option. It is old technology, and not the smallest
physical package, but it does a good job on transients, and the price is
right.

The other professional equipment that I use is definitely outside of your
stated budget. You might start finding the Fluke 43 at a more reasonable
price on eBay, since there are newer instruments now on the market. If you
can get one, it works well for single-phase monitoring. It stores and
displays locally, and can upload to a PC for further analysis.

The other option is to roll your own, as others have suggested. However, I
will also emphasise isolation if you are connecting your PC to the power
line!

Ben Miller
--
Benjamin D. Miller, PE
B. MILLER ENGINEERING
www.bmillerengineering.com


PeterD

2007-02-21, 5:25 pm

On Wed, 21 Feb 2007 15:52:46 -0500, gfretwell@aol.com wrote:

>On Wed, 21 Feb 2007 20:19:14 GMT, Jan Panteltje
><pNaonStpealmtje@yahoo.com> wrote:
>
>
>
>Interesting concept. I bet if you used a compressed format like MP3
>the disk would last for a really long time. Any machine in the faster
>P1 or P11 class can compress on the fly.


Gaah, no! MP3 is a lossy compression--it would loose your spikes and
dips! <bg> Just record it as-is... Disks are cheap.

And, yes, use an isolation transformer!

Charles Perry

2007-02-21, 8:25 pm

Ideal Industries has an interesting low cost product called the Voltage
Performance Monitor. You cannot download data from it or see waveforms, but
it does count events outside of the ITIC curve (update of the old CBEMA
curve) and categorizes them based on type and severity. It is reasonably
accurate in doing this characterization, not something that can be said of
all meters, even more expensive ones.

Charles Perry P.E.
Not an indorsement. I don't have a financial interest, etc, insert legal
weasel words, whatever.


"John E." <incognito@yahoo.com> wrote in message
news:0001HW.C201E807002FC230F01826C8@news.readfreenews.net...
> I'm looking for the most economical means to monitor mains voltage for
> spikes
> and other such disturbances over an unattended period of time.
>
> I see that there are 2 categories of monitoring and logging equipment:
> event
> loggers and samplers. The former requires the setting of thresholds and
> will
> record any event that exceeds these; the latter simply samples the input
> at a
> set interval.
>
> I am looking for a device that records events.
>
> I'd rather avoid the very expensive power quality monitors ($2000-plus
> category). This reduces the list to DMMs with logging capability, which
> includes the Fluke 189. (I'll add that if a data-download option exists, I
> would prefer the ability to review data on the device rather than
> *require*
> that it be downloaded -- I want to be able to, at a glance, confirm that a
> power problem exists, and have the *option* to download the data for
> detailed
> examination if I wish.)
>
> Any other suggestions to achieve my means would be greatly appreciated.
>
> Thanks,
> --
> John English
>



clifto

2007-02-21, 9:25 pm

John E. wrote:
> I'm looking for the most economical means to monitor mains voltage for spikes
> and other such disturbances over an unattended period of time.


I'm not positive of this, but I believe some of the UPS systems that have
cabled monitoring, i.e. hook to your computer via serial port or USB,
will give a power line reading if queried. Don't ask me which ones. I
know my TrippLite 1000VA unit has a front-panel display and I *suspect*
it would tell the computer the line voltage if asked.

--
"Nowadays, security guys break the Mac every single day. Every single day,
they come out with a total exploit, your machine can be taken over totally.
I dare anybody to do that once a month on the Windows machine."
-- Bill Gates, in an interview with Newsweek's Steven Levy
James Sweet

2007-02-22, 3:25 am

John E. wrote:
> I'm looking for the most economical means to monitor mains voltage for spikes
> and other such disturbances over an unattended period of time.
>
> I see that there are 2 categories of monitoring and logging equipment: event
> loggers and samplers. The former requires the setting of thresholds and will
> record any event that exceeds these; the latter simply samples the input at a
> set interval.
>
> I am looking for a device that records events.
>
> I'd rather avoid the very expensive power quality monitors ($2000-plus
> category). This reduces the list to DMMs with logging capability, which
> includes the Fluke 189. (I'll add that if a data-download option exists, I
> would prefer the ability to review data on the device rather than *require*
> that it be downloaded -- I want to be able to, at a glance, confirm that a
> power problem exists, and have the *option* to download the data for detailed
> examination if I wish.)
>
> Any other suggestions to achieve my means would be greatly appreciated.
>
> Thanks,



How about one of these?

https://www.doubleed.com/secure.html
JB

2007-02-22, 9:25 am


"John E." <incognito@yahoo.com> wrote in message
news:0001HW.C201E807002FC230F01826C8@news.readfreenews.net...
> I'm looking for the most economical means to monitor mains voltage for
> spikes
> and other such disturbances over an unattended period of time.
>
> I see that there are 2 categories of monitoring and logging equipment:
> event
> loggers and samplers. The former requires the setting of thresholds and
> will
> record any event that exceeds these; the latter simply samples the input
> at a
> set interval.
>
> I am looking for a device that records events.
>
> I'd rather avoid the very expensive power quality monitors ($2000-plus
> category). This reduces the list to DMMs with logging capability, which
> includes the Fluke 189. (I'll add that if a data-download option exists, I
> would prefer the ability to review data on the device rather than
> *require*
> that it be downloaded -- I want to be able to, at a glance, confirm that a
> power problem exists, and have the *option* to download the data for
> detailed
> examination if I wish.)
>

Fluke VR101S

JB


Geoffrey S. Mendelson

2007-02-22, 9:25 am

John E. wrote:
> I'm looking for the most economical means to monitor mains voltage for spikes
> and other such disturbances over an unattended period of time.


A cheap UPS? Mine can be queryed via a serial port and tells you line
voltage and frequency (along with a lot of other things you probably
don't care about).

Geoff.

--
Geoffrey S. Mendelson, Jerusalem, Israel gsm@mendelson.com N3OWJ/4X1GM
IL Voice: (07)-7424-1667 Fax ONLY: 972-2-648-1443 U.S. Voice: 1-215-821-1838
Visit my 'blog at http://geoffstechno.livejournal.com/
PeterD

2007-02-22, 9:25 am

On Wed, 21 Feb 2007 21:14:45 -0600, clifto <clifto@gmail.com> wrote:

>John E. wrote:
>
>I'm not positive of this, but I believe some of the UPS systems that have
>cabled monitoring, i.e. hook to your computer via serial port or USB,
>will give a power line reading if queried. Don't ask me which ones. I
>know my TrippLite 1000VA unit has a front-panel display and I *suspect*
>it would tell the computer the line voltage if asked.


Now that you mention it, my PowerWare UPS does have this feature, and
a program can record line conditions based on a polling interval.
Probably nto the best solution however since I am sure short (single
cycle) faults will be lost in this setup.

Another alternative is eBay. I see products like the Amprobe monitors
(older, chart type) selling for about $100 or so. Hell, I'll sell mine
for that! <bg>
PeterD

2007-02-22, 9:25 am

On Wed, 21 Feb 2007 18:07:36 -0500, PeterD <peter2@hipson.net> wrote:

>On Wed, 21 Feb 2007 15:52:46 -0500, gfretwell@aol.com wrote:
>
>
>Gaah, no! MP3 is a lossy compression--it would loose your spikes and
>dips! <bg> Just record it as-is... Disks are cheap.
>
>And, yes, use an isolation transformer!


On eBay:

http://cgi.ebay.com/Amprobe-Spike-S...1QQcmdZViewItem

and

http://cgi.ebay.com/AMPROBE-SPIKE-S...1QQcmdZViewItem

both of which do what the OP wants. These units do require special
chart paper which is not cheap, but are solid and dependable units.
Rich Grise

2007-02-22, 1:25 pm

On Wed, 21 Feb 2007 12:13:59 -0800, John E. wrote:

> I'm looking for the most economical means to monitor mains voltage for spikes
> and other such disturbances over an unattended period of time.
>
> I see that there are 2 categories of monitoring and logging equipment: event
> loggers and samplers. The former requires the setting of thresholds and will
> record any event that exceeds these; the latter simply samples the input at a
> set interval.
>
> I am looking for a device that records events.
>
> I'd rather avoid the very expensive power quality monitors ($2000-plus
> category). This reduces the list to DMMs with logging capability, which
> includes the Fluke 189. (I'll add that if a data-download option exists, I
> would prefer the ability to review data on the device rather than *require*
> that it be downloaded -- I want to be able to, at a glance, confirm that a
> power problem exists, and have the *option* to download the data for detailed
> examination if I wish.)
>
> Any other suggestions to achieve my means would be greatly appreciated.
>


Call the power company and see if they'll lend you one.

Good Luck!
Rich


clifto

2007-02-22, 5:25 pm

PeterD wrote:
> On Wed, 21 Feb 2007 21:14:45 -0600, clifto <clifto@gmail.com> wrote:
>
> Now that you mention it, my PowerWare UPS does have this feature, and
> a program can record line conditions based on a polling interval.
> Probably nto the best solution however since I am sure short (single
> cycle) faults will be lost in this setup.


Right. It's only really good for trends. But sometimes faults follow
trends. And it's a whole lot less data to process than, say, 600 Hz
samples of line voltage over a week (362,880,000 samples to check).

--
"Nowadays, security guys break the Mac every single day. Every single day,
they come out with a total exploit, your machine can be taken over totally.
I dare anybody to do that once a month on the Windows machine."
-- Bill Gates, in an interview with Newsweek's Steven Levy
John Gilmer

2007-02-22, 8:25 pm


"**THE-RFI-EMI-GUY**" <rhyolite@nettally.com> wrote in message
news:45dcad53$0$28175$4c368faf@roadrunner.com...
> Please! I hope you mean to have this buffered through an isolation
> transformer!


Why should he?

It's the equivalent of use a "scope" probe to look at line voltage. The
"danger" is at the probe tip but not at the end going to the scope.

There is a question of just how well a transformer will pass the transients.
OTOH, without compensation it's possible that the "voltage divider" may not
properly pass the transients. That's why scope probes were so expensive.


I do grant that a transformer makes it so that if you make a mistake (like
forget to connect the "lower" resistor) you don't have a shock risk.

I have never done this.

I note that "they" now sell the equivalent of the input side of a sound card
that's as big as one's thumb and plugs into the USB port.

Personally, I would like to be able to monitor start up current and voltage
transients when my "heavy stuff" (heat pump and deep well water pump) starts
up.


>



Homer J Simpson

2007-02-22, 8:25 pm


"John Gilmer" <gilmer@crosslink.net> wrote in message
news:45de2d4b$0$21489@dingus.crosslink.net...

> Why should he?
>
> It's the equivalent of use a "scope" probe to look at line voltage. The
> "danger" is at the probe tip but not at the end going to the scope.


No, it isn't. The designer of the scope will have at least contemplated what
happens when you are examining a live circuit at 120 or 240 volts. Will the
designer of the computer have done as much?


--
..

--
..
..
..
..
..
..
..
..

--


**THE-RFI-EMI-GUY**

2007-02-23, 3:25 am

Right! which reminds me some time back, I gave Helga some bad advice
involving live electricity and a swimming pool. She hasn't posted since!

;-P


Homer J Simpson wrote:

>"John Gilmer" <gilmer@crosslink.net> wrote in message
>news:45de2d4b$0$21489@dingus.crosslink.net...
>
>
>
>
>No, it isn't. The designer of the scope will have at least contemplated what
>happens when you are examining a live circuit at 120 or 240 volts. Will the
>designer of the computer have done as much?
>
>
>
>


--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P



ray13

2007-02-23, 9:25 am

On Feb 23, 12:38 am, **THE-RFI-EMI-GUY** <rhyol...@nettally.com>
wrote:
> Right! which reminds me some time back, I gave Helga some bad advice
> involving live electricity and a swimming pool. She hasn't posted since!
>
> ;-P
>
>
>
> Homer J Simpson wrote:
>
>
he[color=darkred]
>
what[color=darkred]
the[color=darkred]
>
> --
> Joe Leikhim K4SAT
> "The RFI-EMI-GUY"=A9
>
> "Treason doth never prosper: what's the reason?
> For if it prosper, none dare call it treason."
>
> "Follow The Money" ;-P


I am still shaking my head, nobody mentioned a GFI.
Isolation transformer is an oxymoron.

I can show anybody how an Isolation transformer won't provide any
isolation what so ever. When that 4800volt line that is over head of
the 220 Mains, drops on the 220 lines, that so called isolation
transformer is toast. It happened to my neighbor. Power company said
it was an act of god. Until the neighbor came up with the defective
splice, (that wasn't crimped) they used on the 4800volt line.

I would use a high speed opto coupler with 6000 volt isolation.

73

N8ZU

Jan Panteltje

2007-02-23, 9:25 am

On a sunny day (Thu, 22 Feb 2007 01:54:17 -0500) it happened "John Gilmer"
<gilmer@crosslink.net> wrote in <45de2d4b$0$21489@dingus.crosslink.net>:

>
>"**THE-RFI-EMI-GUY**" <rhyolite@nettally.com> wrote in message
>news:45dcad53$0$28175$4c368faf@roadrunner.com...
>
>Why should he?
>
>It's the equivalent of use a "scope" probe to look at line voltage. The
>"danger" is at the probe tip but not at the end going to the scope.


There is a little catch here.
The PC case is normally connected to mains ground, and we want the quality
of the line between zero and phase, then without a transformer we also grab
all the noise and stuff between ground and zero.
That could show some peaks in some cases..



R1 |
---------------------- live --------===------------------------| soundcard line in
| |
[ ] R2 |
|____________| soundcard ground
--------------------- zero------------ not |
connected |
|
| PC case
--------------------- ground (safety) -------------------------|_____________

gfretwell@aol.com

2007-02-23, 9:25 am

On 23 Feb 2007 02:13:27 -0800, "ray13" <ray_psi@yahoo.com> wrote:

>I am still shaking my head, nobody mentioned a GFI.
>Isolation transformer is an oxymoron.
>
>I can show anybody how an Isolation transformer won't provide any
>isolation what so ever. When that 4800volt line that is over head of
>the 220 Mains, drops on the 220 lines, that so called isolation
>transformer is toast. It happened to my neighbor. Power company said
>it was an act of god. Until the neighbor came up with the defective
>splice, (that wasn't crimped) they used on the 4800volt line.
>
>I would use a high speed opto coupler with 6000 volt isolation.



If that is your concern you didn't bring enough to the table. The
primary is more like 13kv in most places.
Ben Miller

2007-02-23, 1:25 pm

"ray13" <ray_psi@yahoo.com> wrote in message
news:1172225607.059912.199240@j27g2000cwj.googlegroups.com...
>I am still shaking my head, nobody mentioned a GFI.
>Isolation transformer is an oxymoron.
>
>I can show anybody how an Isolation transformer won't provide any
>isolation what so ever. When that 4800volt line that is over head of
>the 220 Mains, drops on the 220 lines, that so called isolation
>transformer is toast. It happened to my neighbor. Power company said
>it was an act of god. Until the neighbor came up with the defective
>splice, (that wasn't crimped) they used on the 4800volt line.



That doesn't mean an isolation transformer "won't provide any isolation what
so ever". Just that it has a voltage breakdown limit, like every other
transformer and electrical device that connects to the power system. I don't
know what kind of transformer your neighbor used, but there are some
available with breakdown at least equal to the optoisolator that you
proposed.

WIth regard to this thread, an isolation transformer serves a very
significant purpose. Without it, an open neutral connection to the sensing
resistors or an open resistor, would put the entire computer at line
potential with respect to the earth. This could damage the mother board or
something connected to it, or cause an electrocution. An isolation
transformer will prevent this from happening by isolating the line voltage
from the computer. If you disconnect the neutral from the transformer
primary, there will be no voltage on the computer.


Ben Miller

--
Benjamin D. Miller, PE
B. MILLER ENGINEERING
www.bmillerengineering.com


John Gilmer

2007-02-23, 9:26 pm


> There is a little catch here.
> The PC case is normally connected to mains ground, and we want the quality
> of the line between zero and phase, then without a transformer we also

grab
> all the noise and stuff between ground and zero.
> That could show some peaks in some cases..


True.

If your sound card can record stereo, you can make channel 1, "Neutral" and
channel 2, "Hot."


Jan Panteltje

2007-02-24, 9:25 am

On a sunny day (Fri, 23 Feb 2007 21:41:59 -0500) it happened "John Gilmer"
<gilmer@crosslink.net> wrote in <45dfacd3$0$22126@dingus.crosslink.net>:

>
>grab
>
>True.
>
>If your sound card can record stereo, you can make channel 1, "Neutral" and
>channel 2, "Hot."


Exactly, do a differential.
So then split the tracks, and substract with my substract wave program (Linux):
http://panteltje.com/panteltje/dvd/...ct_wave-0.3.tgz
reload the result in a good sound editor, do a FFT.. what not.
One could even listen to it ;-)

**THE-RFI-EMI-GUY**

2007-02-24, 8:25 pm

If a 4800 or 7200 V overhead crossed with the secondary lines to ANY
home, I would expect there would be plenty of damage to go around. In
fact, I doubt a typical opto isolator is big enough (lead distance) to
prevent arc over in the worst case.

ray13 wrote:

>On Feb 23, 12:38 am, **THE-RFI-EMI-GUY** <rhyol...@nettally.com>
>wrote:
>
>
>
>I am still shaking my head, nobody mentioned a GFI.
>Isolation transformer is an oxymoron.
>
>I can show anybody how an Isolation transformer won't provide any
>isolation what so ever. When that 4800volt line that is over head of
>the 220 Mains, drops on the 220 lines, that so called isolation
>transformer is toast. It happened to my neighbor. Power company said
>it was an act of god. Until the neighbor came up with the defective
>splice, (that wasn't crimped) they used on the 4800volt line.
>
>I would use a high speed opto coupler with 6000 volt isolation.
>
>73
>
>N8ZU
>
>
>


--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P



joseph2k

2007-02-26, 9:25 am

John E. wrote:

> I'm looking for the most economical means to monitor mains voltage for
> spikes and other such disturbances over an unattended period of time.
>
> I see that there are 2 categories of monitoring and logging equipment:
> event loggers and samplers. The former requires the setting of thresholds
> and will record any event that exceeds these; the latter simply samples
> the input at a set interval.
>
> I am looking for a device that records events.
>
> I'd rather avoid the very expensive power quality monitors ($2000-plus
> category). This reduces the list to DMMs with logging capability, which
> includes the Fluke 189. (I'll add that if a data-download option exists, I
> would prefer the ability to review data on the device rather than
> *require* that it be downloaded -- I want to be able to, at a glance,
> confirm that a power problem exists, and have the *option* to download the
> data for detailed examination if I wish.)
>
> Any other suggestions to achieve my means would be greatly appreciated.
>
> Thanks,

So rent one.
--
JosephKK
Gegen dummheit kampfen die Gotter Selbst, vergebens.Β_Β_
--Schiller
Frithiof Andreas Jensen

2007-02-27, 9:25 am


"John E." <incognito@yahoo.com> wrote in message
news:0001HW.C201E807002FC230F01826C8@news.readfreenews.net...
>
> I'd rather avoid the very expensive power quality monitors ($2000-plus
> category).


Rent one.


Tzortzakakis Dimitrios

2007-02-28, 1:25 pm


Ο "Frithiof Andreas Jensen" <frithiof.jensen@die_spammer_die.ericsson.com>
έγραψε στο μήνυμα news:es17mp$jk9$1@news.al.sw.ericsson.se...
>
> "John E." <incognito@yahoo.com> wrote in message
> news:0001HW.C201E807002FC230F01826C8@news.readfreenews.net...
>
> Rent one.
>

Or ask for the utility to give you the data-when I told them that I had to
find the data for my thesis, a lady gave me a diskette that had everything,
from load/frequency, to fuel cost.Do you have any contacts with the utility?
>


LinkBot





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