Motion Basics with Brushed Servo

[@traviss7105]

Per your open loop idea with the encoder...I have a cnc lathe that I recently discovered has two feedback sources- an encoder and a resolver. The encoder goes to the motion unit, and the resolver to the drive. Just wanted to share, may help in your applocation. Love the video, very clear!

[@ThriftyToolShed]

Yes, the two feedback devices are very common on CNC machines. At one time I had a small business upgrading old CNC controls. A lot of the older ones used a analog tach for the drive reference feedback and a resolver for the motion. Thanks so much for your comment!

[@Dimitri.van.der.Poorten]

Hi, I have the 12A8E. they have a signal of 5+ and 5-. Can I control that with an Arduino? thanks in any case for the answer.

[@ThriftyToolShed]

I would think so, I have not tried it to say for sure.

[@GregsStoneYard]

The +-5v is just a SOURCE voltage for you to use as you wish. You use the Ref+ and Ref- inputs for control, which are +/- 10vdc, same as he did on this drive. So the Arduiro would need to be capable of outputing a +- 10 vdc signal (ie you need to have a DAC output) Download the www.a-m-c.com/wp-content/uploads/support/reserved/AMC_HWManual_Analog_Panel.pdf

[@bikefarmtaiwan1800]

Thanks for the video- is it possible to replace the step and direction control with just a voltage bias ? Would that be accurate ? I'd love to know .

[@ThriftyToolShed]

Yes, these older servos are actually using a +/- 10 VDC signal. The motion controller is a way to use the digital system and interface. The older servos are naturally analog.

[@jeffwilliams7751]

using a 50k pot. I have 10v+/- at pine 1 and 3. wiper is on ref+. I checked voltage on ref+ and the voltage is moving with the pot. it just doesn't make it to the motor. the dip switches are set to voltage per the data sheet.

[@ThriftyToolShed]

It's been quite a while. I believe inhibit has to be grounded to inhibit so If not connected it should be ok?

[@ThriftyToolShed]

I don't know if you got yours to run. I wanted to mention on my test setup I had only 2 of the dip switches in the ON position for testing and it was 1 & 3. So Voltage Feedback and Current Loop Gain was ON and all others OFF. Also Make sure the Green LED is on and not Red. Hope it helps!

[@박영민-f9t]

What is the difference between +ref in and -ref in? Are the directions of rotation reversed?

[@ThriftyToolShed]

Well this drive had the +/- 10v reference to control the direction and acceleration.

[@000ozzie]

i have stand alone cnc control wired to stepper motors can i use the same controller to run the pwm servo amplifier ??

[@ThriftyToolShed]

Typically as long as they both have the ability to use Step and Direction control inputs. It all depends on your system really.

[@turbothis]

i am using a electro craft 45l and the dang offset cant stop or effect the full rpm run off. you have any lead on the other gain pot settings?

[@ThriftyToolShed]

Not 100% familiar, but if it has a VCS gain, I would try that. VCS gain is ratio adjustment between the input signal and output ( Voltage, Current, Speed) etc. you also have Current limit which can limit the RPM based on current and also the Loop Gain if running in current mode by chance.

[@trikepedaler]

Cool Video, Do you know if this drive will work with glass scales feedback? I have an old Anilam Crusader 2 with Analog servo drives and used a glass scale.

[@ThriftyToolShed]

The drive will not. It is analog tach feedback. The motion controller will accept the glass scales as feedback to the system.

[@jeffwilliams7751]

I have this same drive, when I hook everything up like your video the pot doesn't do anything. Any thoughts?

[@ThriftyToolShed]

Check the configuration. It has to have voltage control selected and also check to make sure your pot is 5K ohms or higher since we can only have 3ma load on the supply.

[@victorrodriguez-ys5tu]

Hi, very interesting video. How can I connect it to my cnc interface to work as well as possible, thanks. (invert control) FW, -, GND, 0-10v, + 10v.

[@ThriftyToolShed]

Hi, At the end of this video is a link to the next video that I uploaded to show how I used a simple encoder set-up to feedback from this motor/drive into Mach 3 via the Ethernet motion controller. Although not all systems are the same I chose to show this one because I do have it running in several older CNC mills I upgraded over the last 10years and it works well with the +/-10v older drives!