Stepping up with a MOT

[Zeke]

Is it possible to step up 10v (from a small hydro gen.) to 120v to power house hold items like TVs and computers with a MOT?

[MRMILSTAR]

I am assuming that this is 10 volts AC RMS. I'm also assuming that the output of the hydro generator is regulated. You would have to remove some turns from the secondary coil. A MOT is designed for an input of about 120 volts and produces an output of about 2000 volts. That's about a 17:1 turns ratio. This is only approximate because all MOTs are slightly different. You would need about a 12:1 turns ratio. The good news is that with only a 10 volt input the MOT will operate much more efficiently because it won't be close to saturation as with a standard MOT.

One problem might be the current draw on the secondary coil. A standard MOT supplies a maximum of about 1 amp on the secondary coil thus its small wire diameter. I don't think you could supply much power because of this. You could possibly power an appliance with up to about 200 watts depending on the wire size of the secondary coil.

[klugesmith]

Please test your MOT idea; it can be a learning experience.
I agree with Steve's points.  Also, the MOT has core shunts to limit output current at normal voltage.   Short circuit I_out will be smaller by the same factor that your voltage is smaller.

On your small hydro turbine, can you replace the 10 V generator with a 120 V generator?
Generator voltage has nothing to do with size or power, just the choice of wire size and turns count in the coils. 
I have some hand-cranked magnetos from early telephone sets. 
Doesn't take much cranking to get electric-shock voltage levels.
Their U-shaped permanent magnets are wrought steel of some kind, because Alnico had not been invented.

[TizianoBll]

1Amp short term, I would say 300mA long term. Plus you would have a large impedance (900 ohm ohmic-inductive) and therefore a voltage drop under load. For example: with no load it outputs 120V, you connect a 100mA load and the output voltage drops to 60V, useless!
To get some power out of it you could remove the high voltage winding and rewind it for 10V but MOT's have low efficency.
Maybe it would better to use a 12V/115V transformer, you would get a little less voltage but il would be more efficient.

[klugesmith]

Hadn't thought of rewinding the secondary of MOT, to become a 10 volt primary.
But to get 120V out from the original 120V winding, you would need to operate with the core even more saturated than in normal MOT operation.

Thy hydro generator frequency is just as important as the voltage,
if you want to raise voltage by transformer instead of rewinding the generator.

We think of MOT's as inefficient, because their normal operating point has more flux density and current density than most power transformers.   I think that if operated at reduced voltage, without core shuts, they'd have ordinary efficiency for a power transformer of that size.  Is that what coilers do with multi-MOT stacks?
 

[Zeke]

the hydro generator is a little 12v where you attach hoses on either side and the water turns the turbine. I blow through it and get 11v, so thats where I get the 10v, an average. I want to step it up to 120v and plug a fish pump in to pump the water back up. Is this possible? Wouldn't that be continuous power generation?

[klugesmith]

Wouldn't it be simpler to get a 12 volt fish tank pump, or similar water pump?

While turbine has water flowing from high to low reservoir, of course you could pump some of the water back up using the generated electricity. Sooner or later, the high reservoir will be dry, except for rain.

Might be more efficient if turbine mechanically turns the water pump.  With gears if necessary to match speeds and torques. 

To minimize the loss (water flow not returned by pump), throttle down the turbine.  To flow of zero.

[MRMILSTAR]

the hydro generator is a little 12v where you attach hoses on either side and the water turns the turbine. I blow through it and get 11v, so thats where I get the 10v, an average. I want to step it up to 120v and plug a fish pump in to pump the water back up. Is this possible? Wouldn't that be continuous power generation?

If I am understanding what you wrote, this sounds like perpetual motion. Like any perpetual motion machine its impossible because of various losses due to heat and friction.