Striatech DVR motor controls

[Richard Shelby]

These questions appliy specifically to the NOVA DVR motor upgrade, but may also apply to other NOVA DVR Striatech controlers. 1) Have you used the "power braking" function and do you think it helps? 2) What about "speed ramp" and torque ramp" functions? 3) "stepping" function - What the heck is this? The new motor works fine (after Technatool sent a replacement and the first one went south -literally-after a week) I really enjoy changing speeds without changing pulleys, but maybe there's more joy to be had. Technatool help files are not much help.

 

[Gary Beasley]

Power braking slows the unit with motor torque opposing the spin. Speed ramp set the acceleration profile especially for when starting at a higher speed, doesnt just max out immediately. Torque ramp is similar except its how fast it builds torque. I think it would also have something to do with how it responds to loading, ie the soft, normal and hard settings in the control.
Not all DVRs will do the power braking, past a certain age it doesnt support it.

 

[Mark Jundanian]

Be careful with the braking feature. The reverse torque can cause the chuck to unscew if you don't use the set screw.

 

[Don Wattenhofer]

{#3 Stepping function} I believe the motor they are using is a stepping motor which is a type used for CNC applications, such as positioning one of the axis on a milling machine. The way it works is the program driving the system translates the new position required into the number of rotational steps required to get it accurately to that point,thus the stepping function.
I have a Grizzly lathe that came with a similar setup to your Nova DVR and the controller fried it self after the warranty was up. The stepper motor had very low torque so rather than replace the controller I bought a 3 phase induction motor and a VFD and made the switch.

 

[Dave Hulett]

Be careful with the braking feature. The reverse torque can cause the chuck to unscew if you don't use the set screw.

Agreed! I tested it once... luckily after tightning the chuck setscrew and was shocked how fast it braked. I could see the disaster that would occur if you forgot to fasten it. sending the heavy chuck and whatever was mounted on it crashing to the floor and on my foot! Since you would have to remember to tighten the set screw every time you put on a chuck, I decided it was safer disable it.

 

[Richard Shelby]

Agreed! I tested it once... luckily after tightning the chuck setscrew and was shocked how fast it braked. I could see the disaster that would occur if you forgot to fasten it. sending the heavy chuck and whatever was mounted on it crashing to the floor and on my foot! Since you would have to remember to tighten the set screw every time you put on a chuck, I decided it was safer disable it.

I tried braking also. Instead of a nice slow deceleration, it was a "CLUNK" - ALL STOP !!. Never gonna try that again. I'll setttle for a handwheel- friction stop. If only there were a big red button that had that function it might be a safety feature. I miss that on the old motor.