STEORN DEMO LIVE & STREAM in Dublin, December 15th, 10 AM

[Omnibus]

@Omega_0,

Your method of calculation is the correct one and is the most direct way to prove OU in this case. We need to know also what the exact weight of the rotor is. I sent an e-mail to Naudin to that effect. No reply yet. As for the shunt, if it is a calibrated shunt the voltage drop measured across the shunt will give you the current precisely.

[k4zep]

Hi OB,

OK, this was the best I could do. See pics below. Motor runs at 180 RPM for an input of 2.2V at 300ma or 0.66 watts.

Approximate rotor weight is 350 grams.

Regards,

Ossie

HI OB,

My rotor weighs 33 GRAMS!!!!!  About 800 ma peak/50% duty cycle, average of 400 ma @ 10 volts, 800 rpm.  Give or take..........or 3.2 watts. 

[Omega_0]

Hi OM,

There is a power supply/battery there just out of sight.  6VDC, big cap. filter. DC current is not right on meter on left, DVM/DIM does not work correctly with that duty cycle, must use scope and current shunt to do it right.  BUT GREAT RUNNING MOTOR!!!!!!

JLN getting ducks in row!

Respectfully
Ben

I guess I mistook the big cap as the power source. There is no explanation of the setup there. You are correct, the readings on the meters are wrong, one needs a scope in such cases.

[Omega_0]

@Omega_0,

Your method of calculation is the correct one and is the most direct way to prove OU in this case. We need to know also what the exact weight of the rotor is. I sent an e-mail to Naudin to that effect. No reply yet. As for the shunt, if it is a calibrated shunt the voltage drop measured across the shunt will give you the current precisely.

Thanks..
Surely, if the shunt is exactly 1 ohm, the scope will read the current directly. Here it is 0.01. I'm a bit confused, because adjusting the scope reading gives 1800 Amp as peak current which is absurd.

[Omnibus]

Sorry Ossie and Ben, one more thing. What's the diameter of your rotor?