ELS Conversion on Weiss 1127

I was relieved to see that the Z scale was reliable by a constant factor and figured that it was the difference in your scales vs mine. I have contacted the seller on AliExpress for the X scale - hopefully if i get another replacement it's not another month. Maybe i should order scales from another vendor in the 1um instead....
 
@WobblyHand While i wait for the scale situation to get solved i would like to make the following enhancements:
  • Ability to configure the direction of the encoder reading so that RPM shows positive direction no matter if the encoder is spinning in the same or opposite direction of the spindle. There may be a need for a factor conversion in here as well; I connected mine 1:1 as you did however there might be some advantage to spinning the encoder faster or slower than the spindle.

  • Ability to adjust the encoder factor to adjust to installed scales. Mine are approximately 5:1 more precise than yours; and this is needed for situations where we mix and match 5um and 1um scales on the same machine i believe.
 
#1. I have implemented an #ifdef in the code to switch the spindle direction sense. It is important for the software to know the direction of rotation, positive rotation should be CCW looking at the spindle from the tailstock end. Negative rotation is CW. This "sign" of rotation is important to maintain, especially if threading away from the spindle, and keeping track of both right handed and left handed threading.

#2. I have implemented common scale calibration factors that are selectable by commenting #ifdef s in the code. The code now supports 0.001 in/div, 5um/div, and 1um/div. The 5um and 1um scales can be mixed, ie. 5um on Z and 1 um on X.

I have tested #2. Yet to test #1. Been shoveling snow the past two days. Had to shovel the roof. Getting some more snow tomorrow.
 
ivel03 said:
I was relieved to see that the Z scale was reliable by a constant factor and figured that it was the difference in your scales vs mine. I have contacted the seller on AliExpress for the X scale - hopefully if i get another replacement it's not another month. Maybe i should order scales from another vendor in the 1um instead....
Click to expand...

Well seeing that it's the Chinese new year i'm betting that i'm not going to hear back about the broken scale for a bit - i hope i can get a refund for the broken one but in the meantime i purchased this one: https://www.aikrondro.com/product/aikron-aums-magnetic-linear-encoder/ I did pull the end caps off the broken scale and the glass is fine but the reader head outside part is separated from the inside part and the tabs that ride inside the seals are broken as well.

The magnetic scale will require drilling some new holes as it mounts a totally different way but it seems even more compact than the Sino KA200 scale which was 16 x 16mm; this is 16 x 9mm but the reader sticks out the side instead of the bottom.
 
Make sure you specify TTL output, not RS422. I know TTL will work. RS422 might require an adapter. I've heard people get lucky and just wire up the + terminals, but that depends on how noisy your shop environment is. But the fallback is an adapter board, which are probably easy to source.
 
Thanks for the heads up - i did look at that a bit and found documentation saying that i may just work which is also what you said. I did request TTL output from the seller but didn't hear back as they're out of the office for Chinese new year. Converter boards are less than $20 so worst case scenario i end up having to purchase that.
 
Well - good news; i tore the broken scale apart and found the tabs broken off. I was able to repair the tab that holds the spring thing that connects the reader head to the outside part with the circuit board in it. I mounted it back on the lathe and it's working now! Reads off by about a factor of 5 just as the other scale does.

I attempted to hook up the stepper tonight and after i had everything wired up i wasn't able to control it with the ELS. The stepper motor was locked up so it appears the controller is powering it.

Is it possible that the ELS isn't telling the stepper to turn b/c the RPMs are negative? What are the ideal settings for the stepper controller? Specifically S1, S2 and S3?
 
ivel03 said:
Well - good news; i tore the broken scale apart and found the tabs broken off. I was able to repair the tab that holds the spring thing that connects the reader head to the outside part with the circuit board in it. I mounted it back on the lathe and it's working now! Reads off by about a factor of 5 just as the other scale does.

I attempted to hook up the stepper tonight and after i had everything wired up i wasn't able to control it with the ELS. The stepper motor was locked up so it appears the controller is powering it.

Is it possible that the ELS isn't telling the stepper to turn b/c the RPMs are negative? What are the ideal settings for the stepper controller? Specifically S1, S2 and S3?
Click to expand...
Great that you could repair the scale!

Locked does mean power. But not necessarily good. Could be that motor wires are not wired correctly. Or it could mean that S1 is set incorrectly.

To answer your question about RPM negative. The stepper will change direction if the RPM is negative, but that is desirable. RPM negative means the controller thinks the lathe is in reverse, in your current SW. The new SW will correct that and be + for forward, and - for reverse.

I will have to check the stepper motor controller settings. They are downstairs in the shop, so the settings are not at my finger tips. I looked them up. This is what I found...

S1 = C, I think, but I need to check on that. For the moment, keep S1 at 0. 0 will not harm anything. However, it may not drive the motor, because of insufficient current.

S2:

SW1-SW4 should be set for 4 microsteps. SW1 = off, SW2 = on, SW3 = on, SW4 = on
SW5-SW8, should be all off, but I need to check this physically

Selector switch S3 = 5V this is important. We are using 5V signaling.

To confirm the settings, I need to open the control box on the lathe. I will do that tomorrow. I tried to see if I had taken a picture of the switches, but apparently didn't take a pic. I will take pictures and report back tomorrow.

You should be wired as shown in Figure 4, of the CLT57T(V4.0) manual.
 
Thanks for the reply. I didn't even think about the negative numbers and the lathe being in reverse - Duh!

I had S1 on 0 but did juice it to A i think in case it couldn't spin the motor for whatever reason. I can't remember what S2 was set to off the top of my head; i will verify settings tonight when i get home. I did move S3 to 5V as i thought you mentioned that we are using 5V for signaling.

Is it possible to test the enable and other signal wires to verify it's sending the proper signals to the driver?
 
ivel03 said:
Thanks for the reply. I didn't even think about the negative numbers and the lathe being in reverse - Duh!

I had S1 on 0 but did juice it to A i think in case it couldn't spin the motor for whatever reason. I can't remember what S2 was set to off the top of my head; i will verify settings tonight when i get home. I did move S3 to 5V as i thought you mentioned that we are using 5V for signaling.

Is it possible to test the enable and other signal wires to verify it's sending the proper signals to the driver?
Click to expand...
S1 should be set to A when everything is running. I just checked that. If there is no load on the stepper, 0 might move the stepper. For the moment, leave it on 0 while debugging, don't want to get anything hot or damaged while figuring out wiring issues!

All the other settings are as I wrote in post #28.

Yes, that's very possible to test the signal wiring. What do you have for test equipment? Volt ohm meter? Scope? Test lamp? Then I can suggest what to do. Please attach a picture of the stepper driver with all the connected wires right now. Maybe there is something that jumps out. Maybe a picture of the cable ends at the ELS controller without the hoods would be useful as well. Basically both ends of the cable you built.

If you have a volt ohm meter, you could set it to ohms or continuity. You could even open the ELS box and ring out the cable. The connector at the top left is J1. You could put one probe on J1, pin 1 and check the pins on the P1 stepper motor connector. This table is from the pins on the PCB to the connector on the stepper motor controller.

Code: 
J1-1 RED +5V   P1 PUL+

J1-2 BLK PUL-  P1 PUL-

J1-3 YEL +5V   P1 DIR+

J1-4 GRN DIR-  P1 DIR-

J1-5 WHT ENA+  P1 ENA+

J1-6 BLU ENA-  P1 ENA-

The table is the intent, with what on my PCB needs to be connected with the CL57T stepper motor controller. It ignores all intermediate connectors. J1 is on the ELS PCB, top left corner. P1 is the Control and outputs connector shown in Figure 2, CL57T(V4.0) connectors.
PXL_20230127_160115212.jpg
1674835465838.png


Here's the best picture I have of the CL57T wired in the box.
PXL_20221023_153243150.jpg
Hope this helps.
 
You must log in or register to reply here.
Back
Top