Old fashioned water wheel powered generator -

[ja2tn]

OK!!  I have a brand new BALDOR Continuous Duty Industrial DC motor that I am planning to use for a generator for an off-grid electrical system. Here are the particulars in the motor as listed on the Baldor website [click here]:

 Specifications: CDP3455

Catalog Number:  CDP3455

Specification Number:  34-5990-3865

Horsepower:  1.00

Armature Voltage:  180

Field Voltage:  PM

Full Load Amps - Armature:  N/A

Full Load Amps - Field:  n/a

RPM:  1750

Frame Size:  56C

Service Factor:  n/a

Rating:  40C

Insulation Class:  F

Form Factor:  n/a

Enclosure:  TEFC

Baldor Type:  3435P

DE Bearing:  6203

ODE Bearing:  6203

Electrical Specification Number:  34WG3865

Mechanical Specification Number:  34LY5990

Base:  RG

Mounting:  F1

Tach Mounting Kit:  n/a

Blower Kit:  n/a

Filter Kit:  n/a

Recommended SCR Control:  n/a

According to the data plate on my particular motor, it lists the Armature Amps as 5 amps.

First, I am getting into this project with my 14 year old son so it is VERY important to me that we learn as much as we can while doing this AND that what we learn is correct.

We hooked the motor up this weekend and powered some lights by turning the motor by hand and are both VERY excited about the project ahead of us.

I am planning to spin the motor somehow [probably by way of a water wheel set-up] at whatever rpm that will produce 48VDC.  This I will send to a bank of batteries [such as the  Trojan Battery L-16HC (420AH) Trojan Deep Cycle Flooded Lead-Acid Battery] by way of a Charge Controller [such as a  Xantrex/Trace C40 Charge Controller] and/or Inverter/Charger [such as a  Xantrex/Trace SW4048 Series II Inverter] and then to power a cabin that hopefully will be my house.  Later I will add on PV panels and batteries to increase the size of the system till it reaches what we need as we expand our cabin into a home

OK... for those of you good at the mathematics part of this process I could use some help.  I need to find out how many watts I can expect to get from this "generator" at the 48VDC I will be running it at.  ALSO... I would like you to explain how you came to the figure so I can learn how to figure this kind of stuff, too.  ANY tips from those of you in the know will be appreciated!!

Also, is there any one out there familiar with using a DC motor for a generator in a set-up like this?  If so I would love to hear ALL about it!!

OK... a quick question that I have: If you are using an inverter/charger combo like the SW4048 from Trace why would you need a charge controller as well?  I was looking at the system on this web page and it looks like they have used both!!

OK... I guess that will do for now!

Thanks,

Jerry

in the mountains of Tennessee

[drdongle]

You dont need to post twice. we'll all see the message.

[ja2tn]

The reason I posted the second one was I noticed that if I looked just in the hydo section my original post wouldn't show up.  So I posted it again in the hydro section.

[finnsawyer]

Since the voltage out is proportional to rpm you need to spin it at about 467 rpm.  Likely as not, you will need to speed up the rpms from the water wheel.  As far as the current out at 48 volts, that depends on the resistance of the armature.  It's probably low enough that you can exceed the 5 amps.  At one horsepower the motor actually should need 4.15 amps.  The rest will cause heating.  That amounts to (180x5) - 748 = 152 watts.  So, measure the armature winding Ra.  The total safe current Is would then be determined by 152 = RaxIsxIs.  In any case be careful and prove these numbers by doing tests and monitoring the temperature of the motor.  I assume the motor has brushes.  The higher currents will shorten their life.  you know the motor will do what you want.  Just use these numbers as a guide and devise a series of tests to determine just what you need to do and what you can really get.  Now that's a real learning experience!

[healerenergy]

Could you please explane where the 180 comes from in this equation (180x5) - 748 = 152 watts. I must have missed it.

[ja2tn]

This is a 180VDC motor!!  I think that is where it comes from.

[hitechguy18]

What type of Wheel are you going to be using?

Types of Water Wheels:

http://www.whitemill.org/z0028.htm

Pitch Back waterwheel/Overshot waterwheel/Breastshot waterwheel/Undershot waterwheel

You have more of a chance of Producing power from: Pitch Back waterwheel/Overshot waterwheel/Breastshot waterwheel Or The generator Will Just Stall the waterwheel when under load.

Don't worry too much about The generator Output Voltages.  

even if it only outputs 24V or 12v You can make use of it by adding Extra gear to "Dubble up the Output" to 115V US or if in the 240V UK To charge a huge Battery bank and then Quad that to run a House load of stuff (Inverter Technology wonderful stuff and should be abused more often!)

So Basicly how it goes:

Water > Wheel > Gen Output: 12v/24v > Inverter Output: 115V/220V @ 650/1000Watts > AC Battery Bank Charger > Charge Regulator > Battery Bank > Inverter Output: 115V/220V @ 2000/4000Watts > House

To Add to that If you put a Relay Switch in That say connected to the Charge Regulator will Auto switch on the Hot water heater/or AC Unit when the Battery Bank is full is a good way to deal with surplus power. Or charge up a 2nd much smaller Emergency Battery Bank.

If you make too much for your need you can always sell it to the Grid

[hitechguy18]

Found a useful link http://www.waterwheelfactory.com/HP%20Table.htm

[ja2tn]

At this point I am leaning towards an overshot that will be fed by a stream or pond [that is fed by the stream] and a millrace (or launder).  Being in the mountains "slope" is not a challenge here, we have plenty.  Plus the overshot is traditional to our area [even several still operating] so that is more than likely what I will go with.

To date I most of my knowledge/experience has been with P.V. and/or diesel/steam/gas turbine generators then onto the battery bank/inverter setup.  But... I came into possession of this motor and decided I want to toy with hydro or wind operated setup.

Thank you for the links and the info I have enjoyed looking at them.  The last I bookmarked as a great reference tool!!  

Thanks again,

Jerry

in the Tennessee Mountains

[finnsawyer]

Yes, as you are putting 180 volts across the motor when using it as a motor.  When using it as a generator most of the heating will be due to the current flowing through the armature.  Given that the motor can safely dissipate only so much heat, the armature resistance then will determine the maximum current.