What is a Three Phase Half Wave Controller?

[ktmrider]

My Tree 330 has a N360 Three Phase Half Wave Controller made by Gould Gettys mounted on it. What does it do?

Another cabinet also has a Kleanline Electronic Filtering System. Any idea what it does for the mill?

Thanks for the help.

Chris

[Al_The_Man]

The 3 phase controller is most likely a DC spindle controller, this uses SCR's set up in a 3 phase bridge to control the phase angle firing point in order to provide rpm control.
This is a very efficient economical way to control a large DC motor.
Early Servo drives used 3 phase fullwave to control large servo motors for CNC control.
They all operate across the incoming power line with no other DC power supply components required.
Al.

[WGoyer]

Chris,

The Gettys N360 is an axis drive. My guess is that your Tree has three of them, one for each axis. On rare occasions, these were used as small spindle drives (5 Hp).

In any case, Half Wave refers to the way the SCRs (silicon controlled rectifiers) are wired up to control the DC going to the motor. Half wave drives have 6 SCRs (three for forward, three for reverse), Full Wave drives have 12. Full wave drives cost more, give smoother motion, and don't need center taps (neutral wires) in their power transformers.

This was a GREAT drive in its day. Thousands are still in use. They were made in Racine, Wisconson. Their tragic mistake was licensing their motor and drive technology to a small, upstart Japanese company called Fanuc in the 70's. The rest is history.

Warren
www.uptimecorp.com

[ktmrider]

Thanks for the info all.