On Wednesday 22 July 2015 01:50:48 Kirk Wallace wrote: > On 07/21/2015 05:16 PM, George Ramsower wrote: > > I have a tread mill motor I got for the purpose of putting it on > > my lathe. I've found a few motor controllers but just haven't > > figured out which one to use. > > What I want is a controller that will control the speed I set it > > at and keep the motor turning at that speed under different loads. > > This would be a normal method of doing this so it's not unusual. > > It's a 120 volt DC motor. > > Thanks for input on this. > > > > George R. > > I have a soft spot for KBIC speed controllers. They use back EMF for > speed feedback and work well from crawling to full speed. Reversing > needs a relay and should not be switched until the motor is stopped. > LinuxCNC can set the speed with a PWM signal to an opto-coupler then > to the KBIC potentiometer input. > http://www.wallacecompany.com/machine_shop/kbic/
I think the controller in my micromill is a kbic, or possibly a clone of one. The switching transistor failed several years ago, so I looked it up and found it wasn't much of a bug. Surveying my pile of defunct computer PSU's I found a bug with 5x the current, double the voltage, and only about 20% more gate capacitance. When and if I replace that 200 watt motor with the 400 watter from the lathe, it won't have a problem running it. It is an extremely stiff control, so stiff I had to put in an ammeter to see how hard it was working as there is no detectable speed sag when the load goes from 120 ma running free to 2 amps and a blown fuse. You can either use the OEM potentiometer to set speed, or something like a mesa Spin1-x(sp?) and control it with linuxcnc. I am running the micromill's spindle with a PMDX-106, so I have the best of both worlds as I can switch back and forth between manual control and computer. Live in real time. PMDX has replaced that model with a different one but I've no experience with the newer version. > > Another driver I have used is Pico-Systems PWM driver which can drive > the motor either way. Speed feedback will need to be with a spindle > encoder then through a LinuxCNC PID or some other control algorithm. > My driver needed to have the output capacitors removed for continuous > operation, but newer drives may not need this modification. The driver > inputs have opto-couplers so the driver signals can be connected > directly to most interface hardware. > https://pico-systems.com/pwmservo.html > > My unfinished use is here: > http://www.wallacecompany.com/machine_shop/Shizuoka/Carousel_Overview- >1a.png > http://www.wallacecompany.com/machine_shop/Shizuoka/100_1136-1a.jpg > http://www.wallacecompany.com/machine_shop/Shizuoka/100_1133-1a.JPG Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ Don't Limit Your Business. Reach for the Cloud. GigeNET's Cloud Solutions provide you with the tools and support that you need to offload your IT needs and focus on growing your business. Configured For All Businesses. Start Your Cloud Today. https://www.gigenetcloud.com/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
