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!

Reply to
jkeagle13
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I have a 40 HP one on ebay right now. It is going to sell pretty cheap check it out.:

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Reply to
Bogone

On 27 Dec 2004 22:15:16 -0800, snipped-for-privacy@aol.com wroth:

---- assuming that the original poster will come back to read replies ---

The government should have plenty of surplus mobile generators available. You know, the ones that have diesel engines and can be towed around behind a big truck. I'll bet you could arrange to "borrow" one of those with suitable output power specifications to allow you to connect directly to your sirens for free.

Jim

Reply to
James Meyer

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.

snipped-for-privacy@aol.com wrote:

Reply to
Marty

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

Reply to
Glen Walpert

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 news: snipped-for-privacy@z14g2000cwz.googlegroups.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! |

Reply to
carl mciver

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 oldtree@pacbell.net
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder
Reply to
Martin H. Eastburn

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)

Reply to
Jerry Martes

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

Reply to
cyberzl1

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.
Reply to
YD

Are you *sure* you can't get your local electric company to provide the three-phase power? They should consider this a mandatory community service, part of their charter, especially considering the importance of protecting the citizenry from overwhelming death by fire. Perhaps the threat of an article or two in the local paper will persuade them to meet their obligations at no extra cost? And if they don't agree, then run those articles, develop some buzz, and ask them again.

--
 Thanks,
    - Win
Reply to
Winfield Hill

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.

Reply to
cyberzl1

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

Reply to
Old Nick

On 31 Dec 2004 07:15:16 -0800, snipped-for-privacy@yahoo.com vaguely proposed a theory .......and in reply I say!:

remove ns from my header address to reply via email

a 7 HP single phase motor will not be quick or easy to source at a cheap price IME. Even 5Hp is unusual.

Reply to
Old Nick

"Old Nick" wrote

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/
Reply to
Nicholas O. Lindan

wrote

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/

Reply to
Nicholas O. Lindan

If you can locate a couple of 75 HP 3ph motors, ( maybe a local rewind shop ) you can build a rather inexpensive rotary phase inverter. If you come across some motors, e-mail me and I will gladly send you some schematics. You'll only need some elecrolytic capacitors, wire, and a contactor for on off control. By the way my son received his Eagle Rank this year. Troop #358 San Antonio, Tx

Reply to
MSHAWO944

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

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
Reply to
keith

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.

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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

Reply to
jkeagle13

I read in sci.electronics.design that snipped-for-privacy@aol.com wrote (in ) about 'WANTED:

50hp Phase Converters - - - Tax Deductible - - EAGLE SCOUT Gov't Service Project', on Sun, 2 Jan 2005:

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
Reply to
John Woodgate

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