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  #1   Report Post  
 
Posts: n/a
Default WANTED: 50hp Phase Converters - - - Tax Deductible - - EAGLE SCOUT Gov't Service Project

Hello,
First of all let me take this opportunity to thank all of you who
by virtue of reading this line have taken time out of your busy lives
in order to do so. I thank you profusely. I am working towards
achieving the highest rank and honor of scouting, by becoming an Eagle
Scout through completing a project as part of the Boy Scouts of America
program.

My project is rather complex in nature and by virtue of this fact
has been difficult to accomplish, with forecasted expenses the
government gave us that come in well over $50,000. For my project we
are going to take two Cold War era civil defense sirens and install
them in a small rural community in Arizona north of Phoenix called Mesa
Del Caballo which is near Payson Arizona, just for a reference point
for anyone who is actually from Arizona. This is a small mountain
community surrounded by the forest. Arizona has been going through a
massive drought over the past years, and as a result, combined with the
disastrous effects of the devastating bark beetle, our forests have
been highly susceptible as of late to pernicious wild fires. My goal is
to set up these two sirens in this community, one on one end, one on
the other, such that if there ever were a forest fire, or other
disaster which required a quick evacuation, the entire town could be
alerted via these sirens which would span all distance and language
barriers.

The government has been extraordinarily helpful to my project so
far by letting us borrow two civil defense sirens each valued at
roughly $25,000. Just to clear up a misconception we can only borrow
the sirens per regulations that were set up before the Cold War when
the sirens were originally installed throughout most of the greater
Phoenix Arizona area. The sirens we are "borrowing" for the project
should never need to be returned, it was just part of the original
contract in case of an extreme unpredictable emergency.

The problem we have run into is that we now have two Cold War era
civil defense sirens, but we don't have the money required to install
them. The representative from the Arizona Government estimated the
actual installation to be somewhere around $75,000. Our estimates upon
further investigation show it to be a smaller figure, but nevertheless
still a massively large amount. The two parts we stand in need of right
now are two 220 volt 50hp phase converters to go from 1 phase to 3
phase. These would be tax deductible, and we can provide proof of their
purpose for this project upon request. We are looking for a spare 50hp
phase converter that can be donated to our project. It does not need to
be new, used or surplus is absolutely fine. The exact specifications of
the civil defense siren are below:

We are starting off with a 220 volt, 200 amp, 1 phase line.
The siren we seek to power has three separate motors.
Motor 1 is a 7hp
Motor 2 is a 4.5hp
Motor 3 is a 1.5hp
RLA is 89amps, 220 volt, 3 phase

I was told by a specialist per these specifications that we needed
a 50hp phase converter. If anyone has a spare they can donate or knows
of a possibility for a donation, or can point us in the right
direction, or has any other helpful information for the project we
would deeply appreciate every little thing we can get at this point!
Thank you for your time in reading this letter. I deeply appreciate it.
In case my email address is blocked as I have begun to notice that many
usenet services do, I will spell it out here. It is: jkeagle13 at aol
dot com

Thank you!

  #2   Report Post  
Bogone
 
Posts: n/a
Default

I have a 40 HP one on ebay right now. It is going to sell pretty cheap
check it
out.:http://cgi.ebay.com/ws/eBayISAPI.dll...e=STRK:MESE:IT

  #4   Report Post  
Marty
 
Posts: n/a
Default

A 10hp phase converter should be more than enough. I have a 7.5hp motor on
my planer and it starts just fine with a 10hp unit. Also, each motor you
have in the circuit running contributes to the total rating.

You should be able to buy a 10hp unit for just a couple hundred if you do it
yourself. Get a pre-made panel for $250 and get a used motor for about
$100.


wrote:

Hello,
First of all let me take this opportunity to thank all of you who
by virtue of reading this line have taken time out of your busy lives
in order to do so. I thank you profusely. I am working towards
achieving the highest rank and honor of scouting, by becoming an Eagle
Scout through completing a project as part of the Boy Scouts of America
program.

My project is rather complex in nature and by virtue of this fact
has been difficult to accomplish, with forecasted expenses the
government gave us that come in well over $50,000. For my project we
are going to take two Cold War era civil defense sirens and install
them in a small rural community in Arizona north of Phoenix called Mesa
Del Caballo which is near Payson Arizona, just for a reference point
for anyone who is actually from Arizona. This is a small mountain
community surrounded by the forest. Arizona has been going through a
massive drought over the past years, and as a result, combined with the
disastrous effects of the devastating bark beetle, our forests have
been highly susceptible as of late to pernicious wild fires. My goal is
to set up these two sirens in this community, one on one end, one on
the other, such that if there ever were a forest fire, or other
disaster which required a quick evacuation, the entire town could be
alerted via these sirens which would span all distance and language
barriers.

The government has been extraordinarily helpful to my project so
far by letting us borrow two civil defense sirens each valued at
roughly $25,000. Just to clear up a misconception we can only borrow
the sirens per regulations that were set up before the Cold War when
the sirens were originally installed throughout most of the greater
Phoenix Arizona area. The sirens we are "borrowing" for the project
should never need to be returned, it was just part of the original
contract in case of an extreme unpredictable emergency.

The problem we have run into is that we now have two Cold War era
civil defense sirens, but we don't have the money required to install
them. The representative from the Arizona Government estimated the
actual installation to be somewhere around $75,000. Our estimates upon
further investigation show it to be a smaller figure, but nevertheless
still a massively large amount. The two parts we stand in need of right
now are two 220 volt 50hp phase converters to go from 1 phase to 3
phase. These would be tax deductible, and we can provide proof of their
purpose for this project upon request. We are looking for a spare 50hp
phase converter that can be donated to our project. It does not need to
be new, used or surplus is absolutely fine. The exact specifications of
the civil defense siren are below:

We are starting off with a 220 volt, 200 amp, 1 phase line.
The siren we seek to power has three separate motors.
Motor 1 is a 7hp
Motor 2 is a 4.5hp
Motor 3 is a 1.5hp
RLA is 89amps, 220 volt, 3 phase

I was told by a specialist per these specifications that we needed
a 50hp phase converter. If anyone has a spare they can donate or knows
of a possibility for a donation, or can point us in the right
direction, or has any other helpful information for the project we
would deeply appreciate every little thing we can get at this point!
Thank you for your time in reading this letter. I deeply appreciate it.
In case my email address is blocked as I have begun to notice that many
usenet services do, I will spell it out here. It is: jkeagle13 at aol
dot com

Thank you!


  #5   Report Post  
Glen Walpert
 
Posts: n/a
Default

On 27 Dec 2004 22:15:16 -0800, wrote:

The problem we have run into is that we now have two Cold War era
civil defense sirens, but we don't have the money required to install
them. The representative from the Arizona Government estimated the
actual installation to be somewhere around $75,000. Our estimates upon
further investigation show it to be a smaller figure, but nevertheless
still a massively large amount. The two parts we stand in need of right
now are two 220 volt 50hp phase converters to go from 1 phase to 3
phase. These would be tax deductible, and we can provide proof of their
purpose for this project upon request. We are looking for a spare 50hp
phase converter that can be donated to our project. It does not need to
be new, used or surplus is absolutely fine. The exact specifications of
the civil defense siren are below:

We are starting off with a 220 volt, 200 amp, 1 phase line.
The siren we seek to power has three separate motors.
Motor 1 is a 7hp
Motor 2 is a 4.5hp
Motor 3 is a 1.5hp
RLA is 89amps, 220 volt, 3 phase

I was told by a specialist per these specifications that we needed
a 50hp phase converter. If anyone has a spare they can donate or knows
of a possibility for a donation, or can point us in the right
direction, or has any other helpful information for the project we
would deeply appreciate every little thing we can get at this point!
Thank you for your time in reading this letter. I deeply appreciate it.
In case my email address is blocked as I have begun to notice that many
usenet services do, I will spell it out here. It is: jkeagle13 at aol
dot com

Thank you!


I would question the assertion that you need a 50hp converter for this
application, especially if you can add a couple of time delay relays
to the controller so that the motors start one at a time. The
required size of the rotary converter can also be reduced by adding
phase correction capacitors to the larger load motors. The actual
size of the converter required depends partly on how much safety
factor the siren designers built in; if the actual mechanical load is
over 80% of the motor rating including the service factor, then a
seemingly oversized converter may really be required. Your local
specialist may have some information on this.

You can get a lot of good information about rotary phase converters
from the rec.crafts.metalworking newsgroup - a lot of the regulars
there use them for their machine tools and some of them have plans
posted in an archive somewhere which they will no doubt refer you to
if you inquire there, or you could find them with a search for "rotary
phase converter" in the newsgroup archives on google groups. I use
the design posted by Fitch (IIRC) and it works well even though I only
use a 5hp converter for a 5hp lathe motor (from which I only require
about 3hp output power, your application is different).

Nice project, good luck with it.

Glen



  #6   Report Post  
carl mciver
 
Posts: n/a
Default

Why not look for VFD's on ebay? Variable frequency drives are capable
of doing the same thing, taking two phases and turning them into three.
Being solid state, they have no moving parts, will not rust out, and are
perfectly capable of doing what you need. The reliability in a system that
will see rare usage I assume is pretty attractive. Take up a whole lot
less space, wiring, and so forth, also. Any competent reliable electrical
contractor will be able to wire one up, and if you talked nicely enough,
he'll liably do it for free.
Even if you don't pay more in up-front costs, shipping will for sure be
a whole lot less!

wrote in message
oups.com...
| Hello,
| First of all let me take this opportunity to thank all of you who
| by virtue of reading this line have taken time out of your busy lives
| in order to do so. I thank you profusely. I am working towards
| achieving the highest rank and honor of scouting, by becoming an Eagle
| Scout through completing a project as part of the Boy Scouts of America
| program.
|
| My project is rather complex in nature and by virtue of this fact
| has been difficult to accomplish, with forecasted expenses the
| government gave us that come in well over $50,000. For my project we
| are going to take two Cold War era civil defense sirens and install
| them in a small rural community in Arizona north of Phoenix called Mesa
| Del Caballo which is near Payson Arizona, just for a reference point
| for anyone who is actually from Arizona. This is a small mountain
| community surrounded by the forest. Arizona has been going through a
| massive drought over the past years, and as a result, combined with the
| disastrous effects of the devastating bark beetle, our forests have
| been highly susceptible as of late to pernicious wild fires. My goal is
| to set up these two sirens in this community, one on one end, one on
| the other, such that if there ever were a forest fire, or other
| disaster which required a quick evacuation, the entire town could be
| alerted via these sirens which would span all distance and language
| barriers.
|
| The government has been extraordinarily helpful to my project so
| far by letting us borrow two civil defense sirens each valued at
| roughly $25,000. Just to clear up a misconception we can only borrow
| the sirens per regulations that were set up before the Cold War when
| the sirens were originally installed throughout most of the greater
| Phoenix Arizona area. The sirens we are "borrowing" for the project
| should never need to be returned, it was just part of the original
| contract in case of an extreme unpredictable emergency.
|
| The problem we have run into is that we now have two Cold War era
| civil defense sirens, but we don't have the money required to install
| them. The representative from the Arizona Government estimated the
| actual installation to be somewhere around $75,000. Our estimates upon
| further investigation show it to be a smaller figure, but nevertheless
| still a massively large amount. The two parts we stand in need of right
| now are two 220 volt 50hp phase converters to go from 1 phase to 3
| phase. These would be tax deductible, and we can provide proof of their
| purpose for this project upon request. We are looking for a spare 50hp
| phase converter that can be donated to our project. It does not need to
| be new, used or surplus is absolutely fine. The exact specifications of
| the civil defense siren are below:
|
| We are starting off with a 220 volt, 200 amp, 1 phase line.
| The siren we seek to power has three separate motors.
| Motor 1 is a 7hp
| Motor 2 is a 4.5hp
| Motor 3 is a 1.5hp
| RLA is 89amps, 220 volt, 3 phase
|
| I was told by a specialist per these specifications that we needed
| a 50hp phase converter. If anyone has a spare they can donate or knows
| of a possibility for a donation, or can point us in the right
| direction, or has any other helpful information for the project we
| would deeply appreciate every little thing we can get at this point!
| Thank you for your time in reading this letter. I deeply appreciate it.
| In case my email address is blocked as I have begun to notice that many
| usenet services do, I will spell it out here. It is: jkeagle13 at aol
| dot com
|
| Thank you!
|

  #7   Report Post  
Glen Walpert
 
Posts: n/a
Default

On Tue, 28 Dec 2004 14:09:52 GMT, Marty
wrote:

A 10hp phase converter should be more than enough. I have a 7.5hp motor on
my planer and it starts just fine with a 10hp unit. Also, each motor you
have in the circuit running contributes to the total rating.

You should be able to buy a 10hp unit for just a couple hundred if you do it
yourself. Get a pre-made panel for $250 and get a used motor for about
$100.


That would be correct for three 1725 RPM machine tool motors which can
start one at a time with low to moderate inertia and no load. Several
factors can significantly increase the converter size required
including higher speed motors (3450 RPM), high inertia load,
permanantly connected load requiring startup into full load (which
often means a different NEMA design class having higher starting
current requirements), load horsepower requirements very close to
motor rating, a requirement that all 3 motors start at once, and
probably a few other factors I don't think of right now.

Perhaps the OP can provide a bit more info on his requirements - all
of the rest of the motor nameplate data including design class,
service factor and speed as well as the startup requirements and the
nature of the connected loads would be good. Probably however lack of
available details will make this a trial and error process, and I
would recommend attempting to borrow a converter for a test before
shelling out cash for a converter that might be too small for your
application.

Use of a static converter (by which I mean a box of capacitors with
controls, not a solid state inverter) rather than a rotary converter
might well require a higher rated unit also, the OP did not specify
what type of converter he was referring to. 7 HP is a bit large for a
single phase input 3-phase output inverter, otherwise 3 inverters
would probably be the best solution.

Glen
  #8   Report Post  
Martin H. Eastburn
 
Posts: n/a
Default

wrote:

Hello,
First of all let me take this opportunity to thank all of you who
by virtue of reading this line have taken time out of your busy lives
in order to do so. I thank you profusely. I am working towards
achieving the highest rank and honor of scouting, by becoming an Eagle
Scout through completing a project as part of the Boy Scouts of America
program.

My project is rather complex in nature and by virtue of this fact
has been difficult to accomplish, with forecasted expenses the
government gave us that come in well over $50,000. For my project we
are going to take two Cold War era civil defense sirens and install
them in a small rural community in Arizona north of Phoenix called Mesa
Del Caballo which is near Payson Arizona, just for a reference point
for anyone who is actually from Arizona. This is a small mountain
community surrounded by the forest. Arizona has been going through a
massive drought over the past years, and as a result, combined with the
disastrous effects of the devastating bark beetle, our forests have
been highly susceptible as of late to pernicious wild fires. My goal is
to set up these two sirens in this community, one on one end, one on
the other, such that if there ever were a forest fire, or other
disaster which required a quick evacuation, the entire town could be
alerted via these sirens which would span all distance and language
barriers.

The government has been extraordinarily helpful to my project so
far by letting us borrow two civil defense sirens each valued at
roughly $25,000. Just to clear up a misconception we can only borrow
the sirens per regulations that were set up before the Cold War when
the sirens were originally installed throughout most of the greater
Phoenix Arizona area. The sirens we are "borrowing" for the project
should never need to be returned, it was just part of the original
contract in case of an extreme unpredictable emergency.

The problem we have run into is that we now have two Cold War era
civil defense sirens, but we don't have the money required to install
them. The representative from the Arizona Government estimated the
actual installation to be somewhere around $75,000. Our estimates upon
further investigation show it to be a smaller figure, but nevertheless
still a massively large amount. The two parts we stand in need of right
now are two 220 volt 50hp phase converters to go from 1 phase to 3
phase. These would be tax deductible, and we can provide proof of their
purpose for this project upon request. We are looking for a spare 50hp
phase converter that can be donated to our project. It does not need to
be new, used or surplus is absolutely fine. The exact specifications of
the civil defense siren are below:

We are starting off with a 220 volt, 200 amp, 1 phase line.
The siren we seek to power has three separate motors.
Motor 1 is a 7hp
Motor 2 is a 4.5hp
Motor 3 is a 1.5hp
RLA is 89amps, 220 volt, 3 phase

I was told by a specialist per these specifications that we needed
a 50hp phase converter. If anyone has a spare they can donate or knows
of a possibility for a donation, or can point us in the right
direction, or has any other helpful information for the project we
would deeply appreciate every little thing we can get at this point!
Thank you for your time in reading this letter. I deeply appreciate it.
In case my email address is blocked as I have begun to notice that many
usenet services do, I will spell it out here. It is: jkeagle13 at aol
dot com

Thank you!

Are you connected to a University or other group ?

Can you not just use a transformer ? Most of us don't have them but
Universities and Power companies do. Maybe you can get a consultant
to the group from the local power company.

Martin

--
Martin Eastburn, Barbara Eastburn
@ home at Lion's Lair with our computer

NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder
  #9   Report Post  
Jerry Martes
 
Posts: n/a
Default


JKeagle

I had expected to read a response from you concerning your more exact
needs regarding this "phase converter". Your project interests me, but it is
unclear if you are hoping for a donation, or if you have interest in
developing a power source for the sirens.
I'm pretty sure you could power your sirens with a much smaller rotary
converter. It could be a real learning project for some electrically
inclined young scout. I'd expect a little (5 HP) idler at each siren could
make all the sound you'd ever need.
If this *is* a real project where only the "results" (siren sounds) is the
goal, and no *overseeing specification writing group* of people need to be
satisfied, I'd voluntere my time and materials to a task like this. I'd
even bring some parts.

I'd sure like to hear more about what your 'constraints" are.

Jerry (who lives about a day's drive away from Payson and
would be willing to drive there)


wrote in message
oups.com...
Hello,
First of all let me take this opportunity to thank all of you who
by virtue of reading this line have taken time out of your busy lives
in order to do so. I thank you profusely. I am working towards
achieving the highest rank and honor of scouting, by becoming an Eagle
Scout through completing a project as part of the Boy Scouts of America
program.

My project is rather complex in nature and by virtue of this fact
has been difficult to accomplish, with forecasted expenses the
government gave us that come in well over $50,000. For my project we
are going to take two Cold War era civil defense sirens and install
them in a small rural community in Arizona north of Phoenix called Mesa
Del Caballo which is near Payson Arizona, just for a reference point
for anyone who is actually from Arizona. This is a small mountain
community surrounded by the forest. Arizona has been going through a
massive drought over the past years, and as a result, combined with the
disastrous effects of the devastating bark beetle, our forests have
been highly susceptible as of late to pernicious wild fires. My goal is
to set up these two sirens in this community, one on one end, one on
the other, such that if there ever were a forest fire, or other
disaster which required a quick evacuation, the entire town could be
alerted via these sirens which would span all distance and language
barriers.

The government has been extraordinarily helpful to my project so
far by letting us borrow two civil defense sirens each valued at
roughly $25,000. Just to clear up a misconception we can only borrow
the sirens per regulations that were set up before the Cold War when
the sirens were originally installed throughout most of the greater
Phoenix Arizona area. The sirens we are "borrowing" for the project
should never need to be returned, it was just part of the original
contract in case of an extreme unpredictable emergency.

The problem we have run into is that we now have two Cold War era
civil defense sirens, but we don't have the money required to install
them. The representative from the Arizona Government estimated the
actual installation to be somewhere around $75,000. Our estimates upon
further investigation show it to be a smaller figure, but nevertheless
still a massively large amount. The two parts we stand in need of right
now are two 220 volt 50hp phase converters to go from 1 phase to 3
phase. These would be tax deductible, and we can provide proof of their
purpose for this project upon request. We are looking for a spare 50hp
phase converter that can be donated to our project. It does not need to
be new, used or surplus is absolutely fine. The exact specifications of
the civil defense siren are below:

We are starting off with a 220 volt, 200 amp, 1 phase line.
The siren we seek to power has three separate motors.
Motor 1 is a 7hp
Motor 2 is a 4.5hp
Motor 3 is a 1.5hp
RLA is 89amps, 220 volt, 3 phase

I was told by a specialist per these specifications that we needed
a 50hp phase converter. If anyone has a spare they can donate or knows
of a possibility for a donation, or can point us in the right
direction, or has any other helpful information for the project we
would deeply appreciate every little thing we can get at this point!
Thank you for your time in reading this letter. I deeply appreciate it.
In case my email address is blocked as I have begun to notice that many
usenet services do, I will spell it out here. It is: jkeagle13 at aol
dot com

Thank you!



  #10   Report Post  
jim rozen
 
Posts: n/a
Default

In article dWrAd.11857$tG3.2944@trnddc02, Jerry Martes says...


JKeagle

I had expected to read a response from you concerning your more exact
needs regarding this "phase converter". Your project interests me, but it is
unclear if you are hoping for a donation, or if you have interest in
developing a power source for the sirens.
I'm pretty sure you could power your sirens with a much smaller rotary
converter. It could be a real learning project for some electrically
inclined young scout. I'd expect a little (5 HP) idler at each siren could
make all the sound you'd ever need.
If this *is* a real project where only the "results" (siren sounds) is the
goal, and no *overseeing specification writing group* of people need to be
satisfied, I'd voluntere my time and materials to a task like this. I'd
even bring some parts.


Hmm. Yep, why does this project sound like one of those "no good
deed goes unpunished" kind of thing?

1) a hit-n-run request, giving an absolute requirement, with no apparent
justification.

2) absolutely no follow-up post to the folks who took the time to make
comments.

3) absolutely no further technical information about the project.

4) governmental participation....

Jim


--
==================================================
please reply to:
JRR(zero) at pkmfgvm4 (dot) vnet (dot) ibm (dot) com
==================================================


  #11   Report Post  
 
Posts: n/a
Default

Hi!
Thank you everyone for the posts. Sorry I did not respond sooner. I
just recently had surgery and I had to go to the hospital yesterday for
a post-surgery visit. I am highly appreciative as I mentioned in my
original post to all of those people who donated their time. I am sorry
it took me this long to respond.

Sadly I can't right now comment on most of the posts as I am not really
an electricity person and understand very very little about any of it,
so it is all Greek to me! I will pass it on to the electrician who is
volunteering his time and I will have him explain it, then we both can
comment and post follow-up questions but for now I am afraid I don't
understand enough of what was said to say anything in response!

I am open to all ideas including the VFD idea. I have no set "has to be
a 50hp phase converter". I thought that was all it could be after a
call to a local shop that specializes in phase converters. I gave them
the requirements and they said the only thing that would work in this
case is a 50hp phase converter, nothing else, which was why I thought
that is what I was set on, finding one of those. I would be happy to
use any alternate solution, especially if it is cheaper. Because I have
so little an understanding of electricity that is the explanation for
why I gave an absolute requirement, is because I didn't realize
anything else existed, but I am glad to utilize whatever works.

Unfortunately in response to one of the comments yes, their is an
overseeing board. The Arizona Emergency Management Services team is
closely monitoring this. We have to have a structural engineer on
board, and everything must be perfectly assembled and inspected to be
up to code. They didn't give the sirens to me and say, "alright, go
have fun now, make them work", the Emergency Management team that deals
with the Civil Defense Sirens are very much involved and oversee every
step of the project so everything has to be satisfactory for them and
up to code. I am not associated with any university. I am still in high
school and I am working on my Eagle Scout project which must be
completed before my 18th birthday in order to qualify for the award.

So I will pass everything on to the electrician. He is very busy but
hopefully sometime this week he can look at the comments and we can
make another response. All the technical specifications I have were in
the original post. I can call my contact with Maricopa to get more of
the specific details if necessary.

To recap. The fire station the first siren we are working on right now
is to be mounted at has a 1 phase 220 volt 200 amp service. The siren
is 3 phase, 220 volt, 100 amp. My assignment was to figure out how to
get from point A to point B, and they suggested the best way would be
to use a phase converter. The only other alternative they said would be
to run the 3-phase lines from the local town of Payson to this rural
community Mesa Del Caballo, but they suggested a phase converter would
be easier and cheaper. I thus called a local machine shop as I said and
gave them everything and they said the only one that could handle it
would be a 50hp phase converter, based upon these requirements:

The three motors to run the siren a
Motor 1 is a 7hp
Motor 2 is a 4.5hp
Motor 3 is a 1.5hp
RLA is 89amps

I can get further details once I know what to ask the siren specialist,
but that is everything I have right now.

I would like to thank everyone who has posted and will post for their
time and help! I will show it all to the electrician and respond with a
better response. I am sure many of the solutions will work though, so
thank you all very much, I wasn't trying to ignore anyone!

  #12   Report Post  
Bruce L. Bergman
 
Posts: n/a
Default

On 29 Dec 2004 11:47:47 -0800, wrote:


To recap. The fire station the first siren we are working on right now
is to be mounted at has a 1 phase 220 volt 200 amp service. The siren
is 3 phase, 220 volt, 100 amp. My assignment was to figure out how to
get from point A to point B, and they suggested the best way would be
to use a phase converter. The only other alternative they said would be
to run the 3-phase lines from the local town of Payson to this rural
community Mesa Del Caballo, but they suggested a phase converter would
be easier and cheaper.


Phase Converters may be easier and cheaper, but they're simply not
as reliable. KISS is a valuable principle to follow. When there is
an emergency and you hit the button for that siren, it needs to work
every time - or why bother putting it up in the first place?

Check with your local power utility about those power lines going
from Payson to Mesa Del Caballo, and feeding through the town. I find
it /very/ hard to believe that they would run a rural power feed any
distance at ALL with only single-phase, since practically all utility
generation facilities (SWAG 99.5% plus) put out native 3-phase, and
almost any commercial or industrial use needs it to work - including
water well pumps on far-flung farms and ranches.

I'm willing to bet that when you get in contact with an engineer at
the local power utility, and he checks the blueprints for the area,
the 3-phase is fairly close by. And I'm sure he can show you how it
all works, and go over the pros and cons of how to run those sirens.

Look at the top set of wires on the pole - if they come in sets of
three, or four with one strung on a set of smaller (lower voltage)
white-glazed insulators, that is 3-phase.

Where the expensive problem can come in is if they don't have the
transformers available already to knock down the 15,000 or 34,500-Volt
transmission line down to the 240-Volt 3-phase that you need.

If the third phase is already at the pole feeding the fire station,
it gets a whole lot easier... Ask the power company to add a second
transformer for a 120/240V 3-Ph "Open Delta" feed like they usually
use for an elevator service. Bada-Bing, you're most of the way there.

You (and the rest of the pack) can do a lot of the mechanical work
yourselves installing a second power meter and service at the Fire
Station to feed the siren - I would use a 200-Amp service and oversize
all wiring and breakers as much as possible for insurance, since this
use is life critical you don't want any nuisance trips of the main
breaker...

Just get that local electrician to show you how it's done and get
you the special-order parts, then he can check your work for obvious
goofs before the local Electrical Inspector comes out for the real
sign-off.

Another way to do it, as has been suggested, is to get a "surplus"
3-phase motor-generator plant to run the siren - and as a bonus, it
can also power the Fire Station in a power outage. You can run the
control electronics, generator starting battery trickle charger and
block heater off the single-phase feed to the FS.

If you stay on top of the maintenance, generators are pretty
reliable, though it will introduce about a 15-second delay while it
starts and comes up to speed before you can start the siren.

-- Bruce --

PS: If I think of it, I'll get you a picture of the old CD Siren
(abandoned in place) in West Hollywood CA, where they have an Onan
gasoline engine direct-coupled to the siren at the top of the lattice
tower, mounted on a big swivel bearing - no big electric motors at
all, just a small 120V utility feed for the battery charger...
--
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop
Electrician for Westend Electric - CA726700
5737 Kanan Rd. #359, Agoura CA 91301 (818) 889-9545
Spamtrapped address: Remove the python and the invalid, and use a net.
  #13   Report Post  
 
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We are starting off with a 220 volt, 200 amp, 1 phase line.
The siren we seek to power has three separate motors.
Motor 1 is a 7hp
Motor 2 is a 4.5hp
Motor 3 is a 1.5hp
RLA is 89amps, 220 volt, 3 phase

I don't know where you came up with 50hp requirement. The motors
themselves only add to 13hp. FOS of 2 only gives you 26 hp. There are
other mitigating factors, but 50hp seems extraordinally over sized.

In any case, is it possible to change the motors out? None of these
are too big to not be used as single phase motors. The biggest factor
would be the mounting type. If you weren't so far away, I could
probably give you at least one of each size, but shipping from my
location would be cheaper to go buy a new one or close to it.

JW

  #14   Report Post  
YD
 
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On Wed, 29 Dec 2004 06:13:29 GMT, "Jerry Martes"
wrote:


JKeagle

I had expected to read a response from you concerning your more exact
needs regarding this "phase converter". Your project interests me, but it is
unclear if you are hoping for a donation, or if you have interest in
developing a power source for the sirens.
I'm pretty sure you could power your sirens with a much smaller rotary
converter. It could be a real learning project for some electrically
inclined young scout. I'd expect a little (5 HP) idler at each siren could
make all the sound you'd ever need.
If this *is* a real project where only the "results" (siren sounds) is the
goal, and no *overseeing specification writing group* of people need to be
satisfied, I'd voluntere my time and materials to a task like this. I'd
even bring some parts.

I'd sure like to hear more about what your 'constraints" are.

Jerry (who lives about a day's drive away from Payson and
would be willing to drive there)



Rotary converters are sooo 60's. Siemens, GE, Allen-Bradley among
others make solid state motordrives of all types and power ratings.
Basically they rectify the incoming power and reconvert the DC to
variable voltage and frequency AC (user defined). This means many
models accept being powered by single phase while driving a
three-phase motor.

- YD.

--
Remove HAT if replying by mail.
  #15   Report Post  
Old Nick
 
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On Fri, 31 Dec 2004 13:06:57 -0300, YD vaguely
proposed a theory
.......and in reply I say!:

remove ns from my header address to reply via email


.....and sooooo cheap G

Rotary converters are sooo 60's.






  #18   Report Post  
 
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They are all over. It just depends on who you ask. Being in Phoenix
area, I don't know all of the farming requirements, but I know up here,
a 5hp motor is pretty common for an auger motor. A 7.5 would be an
average size roller mill motor.

If he needs 3450 rpm motors, find a dairy industry. Nearly all of
their pumps and vacuum motors are run at 3450. Given the area he is
in, I know there is a lot of irrigation done, so I would expect there
are some very large motors running some of that. If it was me, I would
hit up some of the local ag industry suppliers.

A new one would be expensive, but if this project is as noble as he
presents, it wouldn't seem to be that hard to get a few businesses to
donate one.

  #19   Report Post  
Nicholas O. Lindan
 
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"Old Nick" wrote

Rotary converters are sooo 60's.


So are Civil Defense sirens.

"If you see a bright flash immediately duck down and cover yourself
with whatever is at hand. Jim and Judy are shown in this film using
their picnic blanket for thermal radiation flash protection. _They_
didn't let a nuclear blast interfere with their outdoor eating
enjoyment."

--
Nicholas O. Lindan, Cleveland, Ohio
Consulting Engineer: Electronics; Informatics; Photonics.
Remove spaces etc. to reply: n o lindan at net com dot com
psst.. want to buy an f-stop timer? nolindan.com/da/fstop/
  #20   Report Post  
Nicholas O. Lindan
 
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wrote

They are all over. It just depends on who you ask.


Get some old junker motors and learn the art of motor
rebuilding.

--
Nicholas O. Lindan, Cleveland, Ohio
Consulting Engineer: Electronics; Informatics; Photonics.
Remove spaces etc. to reply: n o lindan at net com dot com
psst.. want to buy an f-stop timer? nolindan.com/da/fstop/


  #21   Report Post  
keith
 
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On Sat, 01 Jan 2005 20:09:33 +0000, Nicholas O. Lindan wrote:

"Old Nick" wrote

Rotary converters are sooo 60's.


So are Civil Defense sirens.


No they are *not*! In fact they put them in in the 80's (well after I
left the region).

"If you see a bright flash immediately duck down and cover yourself
with whatever is at hand. Jim and Judy are shown in this film using
their picnic blanket for thermal radiation flash protection. _They_
didn't let a nuclear blast interfere with their outdoor eating
enjoyment."


In the midwest, if you hear a CD siren you'd better find a place to hide
your sorry ass. There is a tornado right on it! They only fire 'em up if
it's on the ground and confirmed, so you'd better know what to do before
you hear it.

--
Keith

  #22   Report Post  
Rich Grise
 
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On Sun, 02 Jan 2005 20:08:41 -0500, keith wrote:

On Sat, 01 Jan 2005 20:09:33 +0000, Nicholas O. Lindan wrote:

"Old Nick" wrote

Rotary converters are sooo 60's.


So are Civil Defense sirens.


No they are *not*! In fact they put them in in the 80's (well after I
left the region).


"If you see a bright flash immediately duck down,


place your head firmly between your knees, and kiss your ass good-bye."

Cheers!
Rich

  #23   Report Post  
 
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Hi,
Thanks again for your replies. I am afraid that I am a little confused
on how we can use anything less than a 25hp phase converter. I am no
expert here, so I am just trying to understand it myself. Just simply
from browsing the internet, and eBay, it appears to me that the
specialist I called was correct in the fact that it needed to be a very
large phase converter. The sirens have a RLA of 89amps, and a mandatory
government safety, has to exist regulation of the phase converter being
able to produce 100amps.

So I am looking for a phase converter to produce 100amps.

A chart I found at the following link states that the phase converter
must be at least a 25hp motor in order to generate 100amps.

http://cgi.ebay.com/ws/eBayISAPI.dll...sPageName=WDVW

So accounting this chart, can I use a smaller motor, like a 7.5hp
motor, and still generate 100amps?

Also, I am getting ready to write a press release in order to gain some
media attention and community support for my project. I have been
persuing over the last several months trying to get APS involved, and
my efforts so far have been in vain. The only returned call from APS
out of many many messages, 6 or 7, possibly more that I have left for
APS was simply to say I had the wrong person, which new person, many
phone messages later, still won't return my calls. So the press release
has many functions. A: Simply to inform the public of my project. B: To
see if someone who reads it knows where there is an unused surplus
phase converter at an old farm or machine shop or something, and C: To
show everyone, specifically at this point APS that I am serious, and
see if a newspaper article might help them jump on the project a little
bit quicker. So I know the technical details of how to circulate a
press release, etc., thanks to my wonderful Eagle Scout Advisor, but I
am just curious on if anyone has any suggestions on what to say or how
to phrase it besides the base explanation of my project. Should we
leave it at simply that, an explanation of the project? Or should we
try and draw public support and donations? Any suggestions would be
greatly appreciated.

Thank you everyone for your time in this matter.
Jkeagle13 (at) aol (dot) com

  #24   Report Post  
John Woodgate
 
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I read in sci.electronics.design that wrote (in
.com) about 'WANTED:
50hp Phase Converters - - - Tax Deductible - - EAGLE SCOUT Gov't Service
Project', on Sun, 2 Jan 2005:
Thanks again for your replies. I am afraid that I am a little confused
on how we can use anything less than a 25hp phase converter. I am no
expert here, so I am just trying to understand it myself. Just simply
from browsing the internet, and eBay, it appears to me that the
specialist I called was correct in the fact that it needed to be a very
large phase converter. The sirens have a RLA of 89amps, and a mandatory
government safety, has to exist regulation of the phase converter being
able to produce 100amps.

So I am looking for a phase converter to produce 100amps.


Something doesn't make sense. Your motors total 13 HP, which is 13 x 746
watts = 9698 W, say 10 kW. This implies a *single phase* 220 V current
of 44 A. To start the motors you will need a current larger than that.

100 A would be a generous allowance for starting if you were using
single phase, but in the three-phase system, the current per phase is
not 44 A but 44/sqrt(3) = 25.4 A, so 50 A per phase would be a generous
allowance.

I think you need more technical advice *locally*, to see why you are
being given inconsistent specifications.
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk
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