Recent content by van4

Great, thanks a lot. I mentioned 0Ω, but what I meant was a very very small Ω :) I was worried that resistors below the 1.25Ω value would cause some sort of problem because if you put the resistance into P=V^2/R, you get a higher power out than you have available. But your comment does make...

I'm required to test a harizontal axis turbine's performance and plot a RPM vs Power curve. The turbine is driving a small DC generator that produces 5V at the turbine's maximum RPM with no other load on the generator. I am planning on installing different sized resistors in parallel with the...

Ok, thanks for your advice. The DC signal is from an encoder, so I'm only measuring the DC pulses on the digital pins of the Arduino. I haven't made the cable yet, so I will combine the digital and analog signals as planned, and see what happens. If I do get interference, would shielding on the...

Hi, I am measuring an analog voltage with an Arduino analog in. The analog voltage comes from a cable which also contains digital signal wires. Do I need to separate the analog and digital signals using separate cables? If so, does the analog voltage signal cable need shielding? And if so, how...

I will be measuring the generated voltage against a range of resistances, as you mentioned, and also measuring the change in RPM. I've been looking into some small DC motors with in-built encoders that I can use for the RPM measurement. The turbine housing is quite restricted for space, so an...

Thanks for your very informative reply! Your project seems interesting. What was the conclusion!? Mine is in fact, very similar. What I will do though, is build a turbine which will be tested in a wave tank with constant velocity. I will then simply add the diffuser while keeping all other...

It's for my thesis research. I see what you mean about the pump, but my aim and method are set out in a different way to the concept you mentioned. I feel like there is light at the end of the tunnel. I think I will use a 12V DC motor from a hobby/robotics shop. I can put a resistor in my...

I'm looking at the difference in efficiency between a standard turbine, and one modified with a diffuser. It has been proven theoretically, but not experimentally. It may be the case if I can't find anything off the shelf. It sounds like an interesting challenge. I'm very well aware of this. I...

My initial thought is - yes, that's what I need. I will have to look into this though. I suspect that the RPM and torque that my turbine provides will be much less than is provided by a large diameter human-powered tyre, driving a small dynamo shaft. Again, I will need to look into this because...

I am very limited for space, so I think I will have to increase the rpm via gears, so that I can keep the size of the motor to a minimum It needs to be smaller than 60mm diameter, and 60mm in length. I don't think I have the expertise to build one myself I had a look, but what I need is much...

Hi all, Does anyone know of, or can anyone point me in the right direction for where to find a small, low rpm generator? RPM can be anywhere in the range of 100-300RPM, and size would be around 50mm long. To put this into context, I am building a small turbine (~300mm diameter), which will...