How to determine size of small electric generator
How to determine size of small electric generator
(OP)
I am designing a small timing circuit and need a power source of around 4 volts and producing around 15 to 20 mA for around 5 to 10 seconds.
I am thinking of using a simple generator (iron core, copper coil) and need to get an idea of how large this needs to be. Can anyone help me with some calculations that I can use to get an estimate on how many coils, size of magnet rotational speed required etc.
Thanks
Steve
I am thinking of using a simple generator (iron core, copper coil) and need to get an idea of how large this needs to be. Can anyone help me with some calculations that I can use to get an estimate on how many coils, size of magnet rotational speed required etc.
Thanks
Steve





RE: How to determine size of small electric generator
Can you give some spec's? couldn't you use a solar cell for
power ?
<nbucska@pcperipherals.com>
RE: How to determine size of small electric generator
RE: How to determine size of small electric generator
Yes, AAA cells would be easier and cheaper, but they don't meet my other requirements as they are far too large for our application, but a single 1/3N cell is possible, if I can overcome the shelf life and temperature limitations that batteries impose.
The timing circuit is only part of it. The power source is also charging a capacitor with sufficient energy to function a device at the end of the delay.
At this stage I am just trying to see if the electric generator idea is feasible with the requirements that I have, but I don't know how large this device needs to be. If I can get some ballpark calculations on required field strength from the magnet and number of coils of the copper and required RPM, I should be able to decide if the idea is worth pursuing further,
Thanks
Steve
RE: How to determine size of small electric generator
Can you tell what this device is ?
<nbucska@pcperipherals.com>
RE: How to determine size of small electric generator
thanks
Steve
RE: How to determine size of small electric generator
besides this... Do you want to supply the DEVICE, too, with
the generator ?
<nbucska@pcperipherals.com>
RE: How to determine size of small electric generator
RE: How to determine size of small electric generator
the timer for a few sec's, this is less than 2 mW -- easy
to generate by a coil/magnet.
<nbucska@pcperipherals.com>
RE: How to determine size of small electric generator
Thanks
Steve
RE: How to determine size of small electric generator
-- single piece -- overdesign it by any acceptable factor.
If massproduct: Start with selecting the cheapest magnet
-- and experiment.
The coil can be the thinnest if the R is low enough -
the duty cycle is so low that it wont overheat.
You may need to build several ones, to get the cheapest
and easiest to manufacture design.
E-mail me as much data as U can.
<nbucska@pcperipherals.com>