In praise of idlers

[Mr. Miyagi]

The motor is a two phase reluctance synchronous motor.For vibration free run a two phase powersupply is the optimal drive , also exact speed adjust is possible on the powersupply.
To show the improvement I made some vibration measurements on the motor itself with a B@K acc.meter first picture shows the drive by mains supply.
Second the two phase powersupply keep a eye on the so called torque vibration at 100 hz all motors driven by mains have these vibrations and the harmonics clearly seen in the picture.
With two phase drive this vibration reduce from-28 db to -61 db which is huge ,also harmonics are strongly reduced
All of this because each coil inside of the motor is driven with his own low distortion poweramplifier and phase and voltage adjust for minimal vibration.
Next picure show the distorted mains voltage drive signals due mains distortion 3-4% thd , and next picture the low distortion voltage from the power supply about 0.4% thd
The sound improvement is also huge and a heavy plinth is not needed anymore.View attachment 152675View attachment 152676View attachment 152677View attachment 152678

Awesome which psu you using?

 

[volken]

Awesome which psu you using?

I build these power supplies myself the one at the picture I have build for example.

 

[Artnet]

I am rebuilding my commonwealth with parts from new zealand. I am increasingly not convinced that uber expensive and overpriced plinths make sense for a commonwealth if the motor and table are properly restored and set up. it should be dead quiet.

Dito, I am following this path and will do a DIY plinth with mine, material to be determined.
It will be interesting to compare measurements when the fully set up commonwealth is running. I am hoping for great things and dont think I am going to be disappointed.
These will be pretty special Idler with what I have heard!