Ecofan mods

[Gypo Logger]

The TEG on my ecofan crapped out, so I turned the motor and fan into a ceiling fan to drive the hot air down as the floor temp is slightly above freezing when it's zero F outside.
Anyway, I hooked up a 12v car battery to the fan, but the rpm was more than the motor was designed for and it broke the mount and took off free flight.
Not to worry, I hooked up a 6 volt lantern battery and that seemed to be ideal rpm.
My question is: what do I need to do to step down amps and or volts so I can use a car battery, as Im not sure how long a 6 volt lantern battery will last.
Thanks for any help, as I am also electrically challenged.
John

 

[beavis331]

It would be nice to have a rheostadt. So you could dial in the speed with a knob.

 

[Gypo Logger]

It would be nice to have a rheostadt. So you could dial in the speed with a knob.

Good idea for sure. You mean like a volume control from a radio?

 

[beavis331]

Yep or a dimmer light switch.

 

[Gypo Logger]

Yep or a dimmer light switch.

Even better, thanks.
Not being the brightest bulb on the tree, should I put the dimmer switch in line with the pos or neg wire?

 

[beavis331]

The pos wire.

 

[Gypo Logger]

Great thanks, I should have known the basics, cause I built a few Heathkits when I was a kid, and they actually worked!

 

[Big_Wood]

john, why don't you just stop being such a cheap bastard and go buy a new one lol yer better off strapping a a regular fan to the roof and run an extension cord up to it with how your going. how long would a battery last 6v or 12v. if you use a battery and ecofan just remember the battery has to be above the fan so you'll have to put it on the roof and drill a hole through roof to run the wire. electricity doesn't flow up

 

[Gypo Logger]

john, why don't you just stop being such a cheap bastard and go buy a new one lol yer better off strapping a a regular fan to the roof and run an extension cord up to it with how your going. how long would a battery last 6v or 12v. if you use a battery and ecofan just remember the battery has to be above the fan so you'll have to put it on the roof and drill a hole through roof to run the wire. electricity doesn't flow up

No! I don't wish to part frivolously with my hard earned firewood profits. Both Ecofans,I found in the dump when I was dumpster diving. To put things into perspective, I live below the poverty level and lovin it!
John

 

[Gypo Logger]

Ecofan mod.

 

[thomasjf]

John, automotive electric radiator fans are 12 volt. Check the late model junkers sitting around. I used an old style aftermarket 12 volt heater control to give a 3 speed. Any heavy wire auto resistor will drop the speed. These fans move a lot of air and at slower speeds are pretty quiet.

 

[Gypo Logger]

John, automotive electric radiator fans are 12 volt. Check the late model junkers sitting around. I used an old style aftermarket 12 volt heater control to give a 3 speed. Any heavy wire auto resistor will drop the speed. These fans move a lot of air and at slower speeds are pretty quiet.

Good plan Thomas, I have a Toyota Tercel rad fan I can speed lip. Solar here is a ****** this time of year.

 

[timbrjackrussel]

You could use a 3 terminal voltage regulator to reduce 12vdc to 5 or 6 vdc with some power loss as heat.
There are also pulse width modulated speed controls, take the speed control out of a 12volt cordless drill.
Hook up a 12v car or deep discharge battery (old scooter) watch the polarity, don't make the magic smoke appear.
http://www.njr.com/semicon/PDF/application_notes/3_TER_VOL_REG_E_REL.pdf
or you could just put two 6 volt fans in series on 12 volts.
Some of the computer power supply cooling fans could also be used.
A larger slower moving fan is better. Think about a small belt drive reduction to an old ceiling fan, with a small 12 vdc
motor.

 

[timbrjackrussel]

The TEG on my ecofan crapped out, so I turned the motor and fan into a ceiling fan to drive the hot air down as the floor temp is slightly above freezing when it's zero F outside.
Anyway, I hooked up a 12v car battery to the fan, but the rpm was more than the motor was designed for and it broke the mount and took off free flight.
Not to worry, I hooked up a 6 volt lantern battery and that seemed to be ideal rpm.
My question is: what do I need to do to step down amps and or volts so I can use a car battery, as Im not sure how long a 6 volt lantern battery will last.
Thanks for any help, as I am also electrically challenged.
John

Yep or a dimmer light switch.

A house light dimmer control won't work on DC.
Get another TEG out of an old Koolatron type cooler.
They may not be used in your part of the world.

 

[Gypo Logger]

Maybe I should switch to this 'beer'?

View attachment 467722

A house light dimmer control won't work on DC.
Get another TEG out of an old Koolatron type cooler.
They may not be used in your part of the world.

Ya, I found that out. I just bought a TEG module on fleabay for 3.49 delivered from China.
Could I not simply put a resistor of the correct ohms between the batt and the motor?
Right now a single D cell is driving it at the correct speed.
Would also becool to run some LED's off the Thermal Electric Generator.
Just trying to do my part in living with a light carbon footprint. Lol

 

[Del_]

Look into small equipment cooling fans. They are cheap, can be bought surplus, don't use hardly any electricity and are quiet if you get the smaller wattage units. The higher powered one can be hooked in series to slow them down and cut back on power usage. The 4.75 inch units work well and can easily move air through dryer type duct work. the 7 watt are real quite. Look for 120 volt ac.

http://www.instructables.com/id/Miserly-Muffin-Fan/

https://www.google.com/search?q=muffin+fans&ie=utf-8&oe=utf-8

 

[Erik B]

Ya, I found that out. I just bought a TEG module on fleabay for 3.49 delivered from China.
Could I not simply put a resistor of the correct ohms between the batt and the motor?
Right now a single D cell is driving it at the correct speed.
Would also becool to run some LED's off the Thermal Electric Generator.
Just trying to do my part in living with a light carbon footprint. Lol

You have to consider the wattage of the resistor also.

 

[timbrjackrussel]

Ya, I found that out. I just bought a TEG module on fleabay for 3.49 delivered from China.
Could I not simply put a resistor of the correct ohms between the batt and the motor?
Right now a single D cell is driving it at the correct speed.
Would also becool to run some LED's off the Thermal Electric Generator.
Just trying to do my part in living with a light carbon footprint. Lol

Ya, I found that out. I just bought a TEG module on fleabay for 3.49 delivered from China.
Could I not simply put a resistor of the correct ohms between the batt and the motor?
Right now a single D cell is driving it at the correct speed.
Would also becool to run some LED's off the Thermal Electric Generator.
Just trying to do my part in living with a light carbon footprint. Lol

If your motor drew .1 amps at 1.5 volts and you wanted to run it off of a 12v battery, then you would have to drop 10.5 volts and at .1 amps this would need a resistor of 10.5 volts divided by .1 amps or 105 ohms
The wattage would be .1 amps times 10.5 volts or about 1 watt. Better to use a larger wattage resistor say 5 watt.
So a 100 ohm 3 or 5 watt resistor would work for this job.
You need to check the current that your motor draws on a good 1.5 volt battery and do the calculation.

 

[Del_]

If your motor drew .1 amps at 1.5 volts and you wanted to run it off of a 12v battery, then you would have to drop 10.5 volts and at .1 amps this would need a resistor of 10.5 volts divided by .1 amps or 105 ohms
The wattage would be .1 amps times 10.5 volts or about 1 watt. Better to use a larger wattage resistor say 5 watt.
So a 100 ohm 3 or 5 watt resistor would work for this job.
You need to check the current that your motor draws on a good 1.5 volt battery and do the calculation.

.1 amp and 1.5 volts comes to only .15 watts. This is a very small fan.

The resistor would be dissipating .1 amp x 10.5 volts = 1.05 watts, 7 times the wattage of the fan. Not a very efficient use of the TEG output.

Maybe a series/parallel arrangement of L.E.D.'s could be used to drop the voltage to the fan and provide light at the same time.

 

[timbrjackrussel]

Good plan Thomas, I have a Toyota Tercel rad fan I can speed lip. Solar here is a ****** this time of year.

You should look into a homemade wind turbine. Carve out a blade, balance, get a small permanent magnet motor as the generator, top a tree, some wire. Lots of fun.