Hi Mark,
Basically the crossflow disintegrated with age (40 years of operation). The site uses an 18" penstock with 40 psi. The pump still uses belts to the old generator since the installation was setup that way, there is some power loss from the belts but better speed matching. With a twelve lead motor one does not need capacitors at all to get a single phase generator. There are some commercial portable diesel systems (30kw) that use this wiring so the site contractor can pick and choose the power type. It is called (I think) a zigzag hook up. One cannot do this with a normal nine lead three phase motor. The system I have is grid connected but my neighbor (from which I used the wiring diagram) has a trailer mounted self regulating twelve lead system with diesel motor. David ----- Original Message ----- From: "H2MJD" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Thursday, January 20, 2005 11:00 AM Subject: Re: [microhydro] Re: Looking for Turbine > > > Hi David, > > Thanks for your reply. > I have some questions....hope you have the time to reply. > Sorry to hear that your crossflow exploded. Was it homebuilt or > commercial? > What caused it to explode? > Your Berkeley pump puts out 22kw at what head? I have 135 ft of static > head w/ a 12 inch penstock. Have you ever measured the flow rate and > computed the overall water to wire efficiency? > Are you able to direct drive the generator or do you need belts and > pulleys. Since most pumps operate at either 1750 or 3500 rpm i was > wondering if you have to gear them up to get to 1850 or 3700rpm. > Maybe thats where i failed in my experiment....i did not gear up........i > just assumed that since my pump was rated at 1750 rpm it would still be > efficient at 1850 when generating. > > Concerning your 15 hp three phase motor......i assume you isolated the the > three leads at the center of the star so that you could isolate and > balance the third phase with capacitors. How many KW can you get out of > it safely and what size caps did you use? I have a 15 hp 1800 rpm motor i > would like to use (perhaps with a pump as turbine)and any info in this > regard would save me many hours of experimenting and headaches. Can you > supply a schematic? > > I know i asked alot of questions but i really like doing this stuff and > have a real hard time understanding "theory" books because of all the deep > math. Any help is greatly appreciated. > > Thanks > Mark > ----- Original Message ----- > From: David Green > To: [email protected] > Sent: Wednesday, January 19, 2005 3:28 PM > Subject: Re: [microhydro] Re: Looking for Turbine > > > > Hi, > > We used a Berkeley pump on one project and it produced an extra 15% over > a > crossflow turbine (which had exploded). It runs a constant 22 kW and has > a > 4" input. > > We also took a 15 hp three phase motor and had it rewired for 12 lead > rather > than nine and have it hooked up for single phase 240 volt operation. > > David > > > [Non-text portions of this message have been removed] > > > > > > > > Does your company feature in the microhydro business directory at > http://microhydropower.net/directory ? If not, please register free of > charge and be exposed to the microhydro community world wide! > > NOTE: The advertisements in this email are added by Yahoogroups who > provides us with free email group services. The microhydro-group does not > endorse products or support the advertisements in any way. > > More information on micro hydropower at http://microhydropower.net > > To unsubscribe: send empty message to > [EMAIL PROTECTED] > Yahoo! Groups Links > > > > > > > > > ------------------------ Yahoo! Groups Sponsor --------------------~--> In low income neighborhoods, 84% do not own computers. At Network for Good, help bridge the Digital Divide! http://us.click.yahoo.com/EA3HyD/3MnJAA/79vVAA/FGYolB/TM --------------------------------------------------------------------~-> Does your company feature in the microhydro business directory at http://microhydropower.net/directory ? If not, please register free of charge and be exposed to the microhydro community world wide! NOTE: The advertisements in this email are added by Yahoogroups who provides us with free email group services. The microhydro-group does not endorse products or support the advertisements in any way. More information on micro hydropower at http://microhydropower.net To unsubscribe: send empty message to [EMAIL PROTECTED] Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/microhydro/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
