Toms Wheels
Titanium
- Joined
- Dec 30, 2005
- Location
- Jersey Shore
There are a number of lathes that have been built with apron mounted controls, which operate low voltage controls for fwd/rev. Monarch has such a system on the 10EE model, called ELSR. Electric Lead Screw Reverse. I had replaced the OEM drive system, with a VFD and 5hp AC motor.
When threading metric threads it is neccessary to leave the half nuts always engaged, which made for a slow return to the beginning point. Yes I could crank the dial abit faster rpm, they slow it do again when threading. Or let the VFD do it for me. All that was needed was one wire and a switch. The apron controls a microswitch, one for fwd, another for reverse, I teed off the reverse control wire through a SPST switch, to the control post on the VFD set to ADD HZ to whatever the VFD is running at. The on/off switch enables or disables the speed increase programmed into the VFD. Since each VFD is different the parameters of my Hitachi would not be much help.
In operation threading at 200rpm is 7hz on the VFD, when the switch is on, and the control lever moved to reverse, it adds 10 hz to the 7, so about 500 rpm in reverse. Works slick.
When threading metric threads it is neccessary to leave the half nuts always engaged, which made for a slow return to the beginning point. Yes I could crank the dial abit faster rpm, they slow it do again when threading. Or let the VFD do it for me. All that was needed was one wire and a switch. The apron controls a microswitch, one for fwd, another for reverse, I teed off the reverse control wire through a SPST switch, to the control post on the VFD set to ADD HZ to whatever the VFD is running at. The on/off switch enables or disables the speed increase programmed into the VFD. Since each VFD is different the parameters of my Hitachi would not be much help.
In operation threading at 200rpm is 7hz on the VFD, when the switch is on, and the control lever moved to reverse, it adds 10 hz to the 7, so about 500 rpm in reverse. Works slick.