Recent content by Baluncore

Here is a crude first guess at what you need. It has max attenuation at VFD 3 kHz, 0 dB at 50 Hz. The motor model is a guess, now configured as Y. Toroids wound for 2 amps, 8mH, wound by the datasheet numbers. VFD is an AC model, so is a zero impedance voltage source.

That is old news, and the asteroid turned out to be much smaller than last time. Remember flight MH370 ?

You need to mark the magnets so we know where the N and S poles are on the surface of those rectangular block magnets.

You do not want any resistance in the path of the current to the motor. A snubber would use a series RC circuit, but not an LPF. For a 3PH LPF you could use inductors to a delta of capacitors, then the motor. Maybe 5mH and 0u47.

Maybe it is quantum mechanics that collapses.

If possible connect the Y of snubbers mid-point to the neutral, avoid a ground connection. If no neutral, design delta a snubbers, or leave the centre floating. Do you have a circuit for the output of the VFD? I would expect an LC low-pass filter. If possible open the VFD and take a look at that...

That is why I suggest fixing the position of the windings, so they are not vibrated and chaffed by the harmonics. A snubber would reduce dv/dt of the voltage spikes. What circuit would you use for snubbers?

Have you considered flooding the field windings with epoxy resin to prevent movement ?

You could check your measurements by employing the white wall as the background, then observing the shaft through a lens, one focal length from the shaft and one focal length from a projection screen. If my Fourier optics is not too cloudy, on the screen you will see repeated bands, the pitch of...

Maybe the inner sanctum, a restricted indoor enclosure for the cat, something that folds up like a child's playpen, floor to ceiling, but with chicken wire and climbing structure on the internal frame. Then a dog flap for the dog to escape the house when it wants. Once they are separated by...

Another way: Place two straight edges against the diameter of the shaft, one on each side. Adjust the edges to be approximately parallel. Use a ruler to measure the edge separation on both sides of the shaft, then average those to find the shaft diameter.

Units police here. 50Ohm has problems. Ohm was a person, so ohm is the unit. 50 ohm is spaced, 50Ω is not. 47 kilohm is contracted, 47 kilo ohm is not. 47kΩ is also correct.

There are few metric or imperial shaft sizes, so there are few bearing inside diameters. The outside diameters depend on bearing construction, so are more variable. The housing is machined to fit the bearing OD. For example, without vernier callipers, it is hard to tell the difference between...

Definitely bigger, but too many turns will saturate the core. What is peak motor current? You need a core datasheet. The aim is to add series inductance to the motor windings, to reduce high frequency voltage appearing across motor terminals. Place a delta of capacitors across the motor...

With TDR of any form, everything beyond the second step or kick, becomes indeterminate pinball insanity, in a hall of mirrors.