power generator meter

[eggpie]

I'm working on a plan to show how much power is created by a human-powered generator in a given amount of time by using a series of colored bulbs.

As more power is generated the bulbs (or potentially just LEDs) light up in series (not sure how many yet, maybe 6-10, so Im thinking about something scalable) until a set amount of power has been generated and all the bulbs are lit. The circuit can then be reset and repeated.

At the moment I've got 24vdc generators, but those can easily be switched out.

I'm really not sure where to start right now. I'm also open to convincing fakery so I'd really appreciate whatever help you can give me..

 

[TrevorP]

LM3914 Search it up.

 

[eggpie]

Thanks. I'd been looking at those. Its an instantaneous thing though? I'm trying to build something thats more..cumulative? The classic analogy would be filling a line of water buckets one at a time until theyre all full. Which makes me think of capacitors...

 

[Super_voip]

ade7756 is a dedicated power meter chip to store the results use a microcontroller(PIC, etc). Alternative read the voltage drop across a very low ohm resistor and store the info on a microcontroller

 

[Leftyretro]

Yes, you need to intergate the generator output over time to get a total power generated value. Some Op amps and some caps should make for a fairly simple design.

Lefty

 

[Nigel Goodwin]

Feed the output of the generator into a resistive load, and have a meter displaying the temperature rise of the load.

 

[chemelec]

Thanks. I'd been looking at those. Its an instantaneous thing though? I'm trying to build something thats more..cumulative? The classic analogy would be filling a line of water buckets one at a time until theyre all full. Which makes me think of capacitors...

An LM3914 with a Sample and Hold Circuit.

 

[Boncuk]

power meter

Hi eggpie,

you'll be amazed how little the human power is compared to a horse power. Consult your doc and have a "ride" on an ergometer being set to 100W ouput. Even if you are well trained and fit the doc will order you to quit after 15minutes. At that time your heart beat frequency will be almost close to death.

Boncuk