J
John Fields
Guest
On Thu, 04 Apr 2013 17:01:07 -0700, John Larkin
<jlarkin@highlandtechnology.com> wrote:
Oh, my!!!
--
JF
<jlarkin@highlandtechnology.com> wrote:
---
Oh, my!!!
--
JF
S
ScottWW
Guest
"Tim Wescott" wrote in message
news:C5CdnXq37r08AsHMnZ2dnUVZ5vidnZ2d@giganews.com...
On Wed, 03 Apr 2013 11:58:42 -0400, ScottWW wrote:
and getting more so, so if the fans really crap out at that point then a
bit of extra margin is a Good Thing. (And as you know, a problem that's
not complained about is a problem that's never addressed). If the noise
issues are really a small fraction of the problems then yes, a modular
solution makes sense.
You _may_ be able to explain the issues and ask the manufacturers if it's
possible to increase the design voltage by 5V or so -- but if the problem
really is rare then I suspect that the cost/benefit analysis won't play
out in your favor (and you may end up having problems with undervoltage,
or needing to increase the expense of the fan to make it work over a
wider range -- there's no free lunch).
handle currents close to your range. These should give you an idea of
the sizes you would really need, but just popping one of these in an
electrical box probably won't meet code (these are all intended to be
built into electronic equipment, not to be mounted in an electrical box
-- I'm sure NEMA would have something to say about using one of these).
Maybe find the manufacturer for one of the bigger transformers you're
looking at, and ask if they can make a 1.5A version?
http://tinyurl.com/d9z86gh
http://www.digikey.com/scripts/dksearch/dksus.dll?FV=fff4000c%2Cfff8012f%
2C19440006%2C19440033%2C19440061%2C19440065%2C1944008d%
2C1944008f&vendor=0&mnonly=0&newproducts=0&ptm=0&fid=0&quantity=0&PV1120=734&PV1120=1160&PV1120=732&PV1120=935&PV1120=994&PV1120=203&PV1120=95&PV1120=324&PV1120=198&PV1120=860&PV1120=402
************************
Thanks for the links.
Scott
news:C5CdnXq37r08AsHMnZ2dnUVZ5vidnZ2d@giganews.com...
On Wed, 03 Apr 2013 11:58:42 -0400, ScottWW wrote:
Faint?
It's not so much that I'm hostile against 'em -- it's that 125V is commonyou bring up some valid points and concerns.
and getting more so, so if the fans really crap out at that point then a
bit of extra margin is a Good Thing. (And as you know, a problem that's
not complained about is a problem that's never addressed). If the noise
issues are really a small fraction of the problems then yes, a modular
solution makes sense.
You _may_ be able to explain the issues and ask the manufacturers if it's
possible to increase the design voltage by 5V or so -- but if the problem
really is rare then I suspect that the cost/benefit analysis won't play
out in your favor (and you may end up having problems with undervoltage,
or needing to increase the expense of the fan to make it work over a
wider range -- there's no free lunch).
I did a quick search on DigiKey for 5V to 6.3V transformers that would
handle currents close to your range. These should give you an idea of
the sizes you would really need, but just popping one of these in an
electrical box probably won't meet code (these are all intended to be
built into electronic equipment, not to be mounted in an electrical box
-- I'm sure NEMA would have something to say about using one of these).
Maybe find the manufacturer for one of the bigger transformers you're
looking at, and ask if they can make a 1.5A version?
http://tinyurl.com/d9z86gh
http://www.digikey.com/scripts/dksearch/dksus.dll?FV=fff4000c%2Cfff8012f%
2C19440006%2C19440033%2C19440061%2C19440065%2C1944008d%
2C1944008f&vendor=0&mnonly=0&newproducts=0&ptm=0&fid=0&quantity=0&PV1120=734&PV1120=1160&PV1120=732&PV1120=935&PV1120=994&PV1120=203&PV1120=95&PV1120=324&PV1120=198&PV1120=860&PV1120=402
************************
Thanks for the links.
Scott
S
ScottWW
Guest
"Jamie" wrote in message news:Yfn7t.303716$Hg7.300608@newsfe30.iad...
George Herold wrote:
some sort of induction coupling, common mode style preferable.
Jamie
**************
I did not know an autotransformer outputs overvoltage. I guess I need to
determine if it is strictly overvoltage, saturation with harmonic noise, or
external noise before I attempt to requisition equipment.
Thanks!
Scott in Dunedin
George Herold wrote:
A variac will hide noise and give you a false conclusion, Hence using
some sort of induction coupling, common mode style preferable.
Jamie
**************
I did not know an autotransformer outputs overvoltage. I guess I need to
determine if it is strictly overvoltage, saturation with harmonic noise, or
external noise before I attempt to requisition equipment.
Thanks!
Scott in Dunedin
S
ScottWW
Guest
"John Fields" wrote in message
news:9tbtl8p3gsg2m4a8sa64pdrs1p5ki1mln2@4ax.com...
On Thu, 04 Apr 2013 17:01:07 -0700, John Larkin
<jlarkin@highlandtechnology.com> wrote:
Oh, my!!!
--
JF
***************************
I appreciate the description of the best lure.
Quick research into inductor calculations gave me a haddock.
Thanks!
Scott
news:9tbtl8p3gsg2m4a8sa64pdrs1p5ki1mln2@4ax.com...
On Thu, 04 Apr 2013 17:01:07 -0700, John Larkin
<jlarkin@highlandtechnology.com> wrote:
---
Oh, my!!!
--
JF
***************************
I appreciate the description of the best lure.
Quick research into inductor calculations gave me a haddock.
Thanks!
Scott
S
ScottWW
Guest
"Jamie" wrote in message news:Yfn7t.303716$Hg7.300608@newsfe30.iad...
George Herold wrote:
some sort of induction coupling, common mode style preferable.
Jamie
*************************
In an effort to determine whether it is line noise or simply overvoltage, it
seems an autotransformer could recreate a clean overvoltage in our facility
for testing. Please clarify how the autotransformer would "hide noise". By
cleaning up the mains power? Would it also mitigate the internal harmonics
from saturation problems? It would be preferred if it didn't for testing
purposes.
I am hazy on "induction coupling, common mode style". Does this refer to a
choke? To reduce voltage and clean up the waveform? This is more
accurately addressing the subject line, but I think I 'm off on a tangent
now, about testing.
Thanks!
Scott in Dunedin
George Herold wrote:
A variac will hide noise and give you a false conclusion, Hence using
some sort of induction coupling, common mode style preferable.
Jamie
*************************
In an effort to determine whether it is line noise or simply overvoltage, it
seems an autotransformer could recreate a clean overvoltage in our facility
for testing. Please clarify how the autotransformer would "hide noise". By
cleaning up the mains power? Would it also mitigate the internal harmonics
from saturation problems? It would be preferred if it didn't for testing
purposes.
I am hazy on "induction coupling, common mode style". Does this refer to a
choke? To reduce voltage and clean up the waveform? This is more
accurately addressing the subject line, but I think I 'm off on a tangent
now, about testing.
Thanks!
Scott in Dunedin
G
George Herold
Guest
On Apr 4, 6:36 pm, Jamie
<jamie_ka1lpa_not_valid_after_ka1l...@charter.net> wrote:
fans make noise because of a slight over voltage... or is it noise on
the line?
George H.
<jamie_ka1lpa_not_valid_after_ka1l...@charter.net> wrote:
No, I meant the variac to only test the over-voltage part. Do the
fans make noise because of a slight over voltage... or is it noise on
the line?
George H.
J
John Larkin
Guest
On Fri, 5 Apr 2013 09:29:19 -0400, "ScottWW" <spamtrap@dcorp.com>
wrote:
JF has been studying his cliche book again, and not his EE texts.
--
John Larkin Highland Technology, Inc
jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com
Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro acquisition and simulation
wrote:
The subject is acoustic noise from an induction motor. Not fish!
JF has been studying his cliche book again, and not his EE texts.
--
John Larkin Highland Technology, Inc
jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com
Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro acquisition and simulation
J
John Larkin
Guest
On Thu, 04 Apr 2013 18:48:43 -0500, Jamie
<jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote:
--
John Larkin Highland Technology, Inc
jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com
Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro acquisition and simulation
<jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote:
Variacs are usually pretty wideband, up to a KHz at least.
--
John Larkin Highland Technology, Inc
jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com
Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro acquisition and simulation
J
Jamie
Guest
ScottWW wrote:
location and the noise will fade as you go above or below.
You really should monitor the voltage with a scope to see what it
looks like. I've seen a lot of distorted wave forms due to heavy and
uneven loads in the service area, mostly when it's hot and every one
is operating their air.
In the summer at work, we get back power to the machines due to heavy
loads we have operating from all the air handling units.. You can hear
the inverter drives doing random singing on units that do not have a
isolation transformer or line rectors.
In many cases with the 3 phase equipment we need no less than a 1:1
transformer for voltage sensitive devices. This is because there is a
3 phase floating delta and when a leg gets shorted somewhere, which
will not most of the time cause a problem directly, it will cause many
inverter drive types to sense over voltage and shut down. Some times it
actually burns out the sensing circuit in the drives and thinks it is
looking at over 800v on the bus, when it is only seeing 600 at the DC bus.
Have fun.
Jamie
and with a auto transformer, this will happen unless you are at the 1:1
location and the noise will fade as you go above or below.
You really should monitor the voltage with a scope to see what it
looks like. I've seen a lot of distorted wave forms due to heavy and
uneven loads in the service area, mostly when it's hot and every one
is operating their air.
In the summer at work, we get back power to the machines due to heavy
loads we have operating from all the air handling units.. You can hear
the inverter drives doing random singing on units that do not have a
isolation transformer or line rectors.
In many cases with the 3 phase equipment we need no less than a 1:1
transformer for voltage sensitive devices. This is because there is a
3 phase floating delta and when a leg gets shorted somewhere, which
will not most of the time cause a problem directly, it will cause many
inverter drive types to sense over voltage and shut down. Some times it
actually burns out the sensing circuit in the drives and thinks it is
looking at over 800v on the bus, when it is only seeing 600 at the DC bus.
Have fun.
Jamie
J
Jamie
Guest
ScottWW wrote:
Read the first couple of sections
Jamie
http://www.exergia.info/Lightning/lightning7.htm
Read the first couple of sections
Jamie
M
Michael A. Terrell
Guest
ScottWW wrote:
It depends to the model of the Variac, and how it's connected. The
standard model doesn't boost the voltage. The other type can be fed
from a tap, and with 120 VAC in can give 0-140 VAC out. Be careful with
anything Maynard Philbrook (AKA: Jamie) tells you.
It depends to the model of the Variac, and how it's connected. The
standard model doesn't boost the voltage. The other type can be fed
from a tap, and with 120 VAC in can give 0-140 VAC out. Be careful with
anything Maynard Philbrook (AKA: Jamie) tells you.
J
John Fields
Guest
On Fri, 05 Apr 2013 10:53:49 -0700, John Larkin
<jlarkin@highlandtechnology.com> wrote:
Not a cliche at all, just a variation of: "Give a man a fish and
you've fed him for a day; show him how to fish and you've fed him for
the rest of his life."
My point was that your answer was simplistic and didn't really convey
anything helpful other than: "If that, then this", without really
delving into the "that",and all the while sending him out to buy a lot
of chokes.
I think that's what we've come to expect from you.
--
JF
<jlarkin@highlandtechnology.com> wrote:
---
Not a cliche at all, just a variation of: "Give a man a fish and
you've fed him for a day; show him how to fish and you've fed him for
the rest of his life."
My point was that your answer was simplistic and didn't really convey
anything helpful other than: "If that, then this", without really
delving into the "that",and all the while sending him out to buy a lot
of chokes.
I think that's what we've come to expect from you.
--
JF
J
John Fields
Guest
On Fri, 05 Apr 2013 10:55:16 -0700, John Larkin
<jlarkin@highlandtechnology.com> wrote:
Got some data to support your claim?
--
JF
<jlarkin@highlandtechnology.com> wrote:
---
Got some data to support your claim?
--
JF
J
Jim Thompson
Guest
On Tue, 09 Apr 2013 17:07:07 -0500, John Fields
<jfields@austininstruments.com> wrote:
...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
<jfields@austininstruments.com> wrote:
Even us atheists know about teaching how to fish >:-}
...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice
480)460-2350 Fax: Available upon request | Brass Rat || E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
J
Jim Thompson
Guest
On Tue, 09 Apr 2013 17:10:14 -0500, John Fields
<jfields@austininstruments.com> wrote:
...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
<jfields@austininstruments.com> wrote:
Larkin? DATA? You've got to be kidding.
...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice
480)460-2350 Fax: Available upon request | Brass Rat || E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
J
John Fields
Guest
On Tue, 09 Apr 2013 15:12:46 -0700, Jim Thompson
<To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:
Silly me...
--
JF
<To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:
---
Silly me...
--
JF
J
John Larkin
Guest
On Tue, 09 Apr 2013 17:07:07 -0500, John Fields
<jfields@austininstruments.com> wrote:
--
John Larkin Highland Technology, Inc
jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com
Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro acquisition and simulation
<jfields@austininstruments.com> wrote:
Trivial, tedious, predictable fathead.
--
John Larkin Highland Technology, Inc
jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com
Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro acquisition and simulation
J
Jim Thompson
Guest
On Tue, 09 Apr 2013 18:00:20 -0500, John Fields
<jfields@austininstruments.com> wrote:
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
<jfields@austininstruments.com> wrote:
This is getting to be fun. Imagine... me playing the straight man
...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice
480)460-2350 Fax: Available upon request | Brass Rat || E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
J
John Larkin
Guest
On Tue, 09 Apr 2013 18:00:20 -0500, John Fields
<jfields@austininstruments.com> wrote:
contribute, and you only seem to admire one another. Your only
remaining skill is whining at people who are interested in
electronics. The rest of your life will only be worse.
--
John Larkin Highland Technology, Inc
jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com
Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro acquisition and simulation
<jfields@austininstruments.com> wrote:
You two old gits are sad. You have nothing to say on-topic, nothing to
contribute, and you only seem to admire one another. Your only
remaining skill is whining at people who are interested in
electronics. The rest of your life will only be worse.
--
John Larkin Highland Technology, Inc
jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com
Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro acquisition and simulation
J
John Larkin
Guest
On Tue, 09 Apr 2013 17:10:14 -0500, John Fields
<jfields@austininstruments.com> wrote:
them.
--
John Larkin Highland Technology, Inc
jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com
Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro acquisition and simulation
<jfields@austininstruments.com> wrote:
As I recall, you were wrong about Variacs the last time we discussed
them.
--
John Larkin Highland Technology, Inc
jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com
Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro acquisition and simulation