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Got a 12v

Tue, 01/03/2017 - 11:42
Ok I finally got a 12v battery. Can anyone tell me if this would work? If not I am going to take it back.

Duracell Marine and RV 24DC
MCA @ 32 degrees F - 685
CCA @ 0 degrees F - 550
Average mins @ 23 amp draw - 140

Re: Can we discuss electric motor modding here

Tue, 01/03/2017 - 09:28

 joestue, just for my understanding, I found out the GM alternator motor uses a technology that PULLS the rotor around vs PUSHES the rotor around.  Would this help any in the power output of PM vs induction.

 I understand what you wrote before. I am j...

Re: 48V alternator (ICE driven)

Tue, 01/03/2017 - 02:06
Have to agree, anything rescued free from the tip at zero cost is definitely a bargain.

I suppose if you desperately wanted to try a PM alternator, a brass shaft might be  up to the job.
If I was doing this myself I would just rewind the field for 48v....

Re: 48V alternator (ICE driven)

Tue, 01/03/2017 - 01:31
In practice I think a n45 neo that big would possibly saturate the shaft it would behave as a non-magnetic shaft anyway......plenty of lines left for the job I suspect

But I agree with Warp, it would be a backward step, particularly seeing how simple a...

Re: Can we discuss electric motor modding here

Mon, 01/02/2017 - 21:55

 Thanks for your input, joestue. Much appreciated.

Re: Can we discuss electric motor modding here

Mon, 01/02/2017 - 18:35
Fundamentally you have a problem with permanent magnet motors for Ebikes and cars, without transmissions you have a wide range of voltage produced by the motor. the rpm speed limit is set by the battery voltage. also at high speed you have a lot of edd...

Re: 48V alternator (ICE driven)

Mon, 01/02/2017 - 16:53
Yes, I see what you mean. 
It could still be done, but the steel shaft is a definite problem to be overcome for PM operation.
A permanent magnet modification would still be a backward step IMHO.

Re: 48V alternator (ICE driven)

Mon, 01/02/2017 - 16:43
Not without a non magnetic shaft.

Re: 48V alternator (ICE driven)

Mon, 01/02/2017 - 16:31
That would certainly work, and so would several rare earth magnets placed around in there, instead of the bobbin winding. Whatever you decide, once the steel has magnetically saturated, there is no further increase in alternator output.  So there is no...

Re: 48V alternator (ICE driven)

Mon, 01/02/2017 - 15:53
Since you have the rotor apart, I think 2 Microwave ring magnets will fit in there, replacing the coil.

Re: 5kw Poncelet Wheel Project

Mon, 01/02/2017 - 13:29
I'll have a better idea of the payback once I get it into the water and see how it works. I'm pretty sure I'll cover my own electrical needs. How much I'll export is the question.

Can we discuss electric motor modding here

Mon, 01/02/2017 - 07:30
 He is discouraged by the less than anticipated output being produced as a typical induction motor. So, instead of cluttering up his thread, in case he hits on an acceptable solution, I would like to see if anyone here can jump on how to make this moto...

Re: 48V alternator (ICE driven)

Sun, 01/01/2017 - 18:59
Yes indeed, but the output power will be pretty considerable as well.

Quotekeep in mind the eddy currents set up in the iron oppose the field coil's amp turns. so the volts per hz will decrease as rpm rises..Yes, and that is very important. ...

Re: 48V alternator (ICE driven)

Sun, 01/01/2017 - 18:35
I suppose I should confess I am now rather curious what kind of power a car alternator will suck up at 20,000 rpm with a full field exciton of 4 amps at 12 volts.

my guess is there will be about 1 hp of air drag and eddy current losses. but at 20,000 r...

Re: 5kw Poncelet Wheel Project

Sat, 12/31/2016 - 19:01
You certainly have more patience than I but can't say more than that for fear of being chastised for being " Political".

How much to you envisage this project saving you on power a year and what do you estimate the payback time on your investment?

Re: Giving Fido a Drink

Sat, 12/31/2016 - 18:49
I think that is the secret George, small but frequent refills. A bit of overflow keeps it pretty clean.

When I first did this bird bath thing it was really amusing.
The birds would come, drink daintily, then get in and splash around a bit.  They would ...

Re: Giving Fido a Drink

Sat, 12/31/2016 - 18:28

And here's me just putting the bowl in the shower with a slow drip.

Friend of mine has a  plastic crate of about 20L for his dogs water and has an electronic sprinkler timer on the tap above for 1 minute 3 times a day.
Cleans out the trough and keep...

Re: Giving Fido a Drink

Sat, 12/31/2016 - 16:37
I have done almost the exact same thing to keep a bird bath full of clean and regularly changed water.

If you use a reasonable length of small bore pipe between the solenoid valve and what is being filled, the water flow is not that high, so the timer ...

Re: 5kw Poncelet Wheel Project

Sat, 12/31/2016 - 13:16
It's been two years since I applied, but I finally received my License of Occupation and my Conditional Water license which is the gov't's blessing to proceed with the project. Unbelievably there are still additional conditions which I must meet before...

Giving Fido a Drink

Sat, 12/31/2016 - 12:29
I have to leave town next week for ten days. I have a friend that is going to come and
feed the dog. Now he is a dog person,but he still thinks my dog is nuts and will eat him.
I decided he needed to limit his exposure to Rosie and just in case he miss...