Replacing Advanced Motion Controls "brush type 12A8 with "Axcent" amplifier

Ideally the encoder signal should be either 0v or 5v (and changing from one to the other as you very slowly turn it.)

If the encoder signals don't ever drop below 2v then the 7i77 will not see the transitions.

What is the part number of the replacement encoder?

Todd, many thanks! This was per USDigital recommendation, all the parts:

EM1-2-500-N
www.usdigital.com/products/encoders/incr.../modules/EM1-2-500-N

Todd, I asked the tech at USDigital the question, this is the response:
"The encoder output signal is a digital square wave on both the A and B channels. The high portion of the square wave signal will be near 5V, while the low portion of the square wave will be near 0V (0.5V maximum)."

HUBDISK-2-500-500-NE
encoder wheel:
www.usdigital.com/products/encoders/incr...HUBDISK-2-500-500-NE

CA-LC5-W4-NC-1
Cable&Connector
www.usdigital.com/products/accessories/cables/CA-LC5-W4-NC-1


Many thanks!

I know, but that wasn't what you measured. You said you found between 4.7-5.2, nowhere near the 0v lows. Do you have access to a real oscilloscope and know how to use it? You may need to look at the encoder's output with one. Otherwise double check that you have the encoder correctly installed and wired. It's possible to plug that pigtail in backwards.

Many thanks, Todd. I have found that yes you are correct the encoders were plugged in backward. This did not change what I measured. In addition to en-shore that good connection was being made, put short lead under screw (type of temporary connection), alligator temps to voltmeter, to test today. No, I don't have oscilloscope and know how to use it. In all fairness the volt meter is a cheep one (thinking it may not be quick enough, but with motor shaft stopped, no motion that I can feel, should it read 0.0V at random stopped points), not brand name like central tractor brand.

many thanks

From tracking info this morning, new 7i77 card may be here today!!!!

Hopefully connecting the new encoder backwards did not kill it.

Todd, USPO just delivered (as per USPO promise of 3:00 PM delivery) new 7i77 card, tomorrow I will swap out, change jumpers position, review SW1 positions & use last wiring diagram (using pins 9 & 11). Todd, many thanks, for your continued support.

New 7i77 card installed, jumpers w10,13,15,17,19 & 21 to the left; SW1-1=OFF,-2=OFF,-3=OFF,-4=OFF,-5=ON & -6=OFF. The x axis runs away, as soon as e-stop is released (the yellow that shows motion of tool, that "ctrl+k clears" will be visible), if you set SW1-5=OFF the red LED is on driver, will slow the speed, still does not match DRO. The y axis osculates about a 1/3 turn, and then will oscillate back the 1/3 turn. Attached is a pic of debug info if you try to run linuxcnc w/o power to power supply.

Many thanks

Many thanks!! With linuxmint running, release e-stop and x axis motor starts motion, start linuxcnc and DRO is counting (the yellow line was moving off the screen to the right). The direction of the motor (as to move table as you stand in front of mill as to operate it, the table moves to left), I believe this matches DRO direction. All of this is while (F1, is clicked) if you release f1, no change; click f2 no change to DRO but (joint 0 error) will appear.

Y axis (as 1st boot up) DRO is moving (the DRO will start at 0.0 go to around +.028 & then go back to 0.0), very close to how x axis is working; if you try to turn motor shaft, it will resist, if quickly reverse direction you are tiring to turn shaft, it will resist; with f1 un-clicked and turn shaft will get (joint 0 error), I believe the joint error happens as soon as click f2.

Many thanks

Edit: Using HAL Configuration, under "Machine tab" (the screen says "show/watch" select a Leaf), what Leafs should I be watching? I look at say Pins, axis, 0; (top of list) Active, the yellow circle shows; I pick Motor-pos-cmd this will say 123.491. It is my thinking that the encoders need the e-stop released to start counting. I am not shore where I should be looking or testing.
Many thanks

Many thanks, to all the members. Read USDigital information about location hub of the disk for encoder, the proper distance. After reset of the encoder hubs (center is not correct) with the e-stop released, start linuxcnc and motors are in motion; un-click F1 and click F2 and motors will stop, DRO will read correctly (at least direction: x table moves to left=positive DRO: Y moves table away from operator= negative on DRO); if you turn motor too fast or reverse direction it will have "joint 1 following error". All seems ok, but if you spin too fast or reverse direction then error will appear.
Many thanks!

Edit: Encoder info attachment:

new2linux wrote: After reset of the encoder hubs (center is not correct) with the e-stop released, start linuxcnc and motors are in motion; un-click F1 and click F2 and motors will stop,

Sorry to repeat this, but that should not be happening under any circumstances, ever.
Drives/motors should not be enabled and moving until enabled in LinuxCNC and actually told to move.

tommylight, many thanks for you help! I have used ohm meter to trace each lead from the encoders to the TB3 connection, so with 100%, know where each lead is connecting. I found issues, did not record them. Removed the leads from TB3 that are not being used (2 & 5).
Now with linuxmint running, release e-stop and motors are in motion, open linuxcnc, DRO is reading ok and F1 is down; x axis is run away, at low speed; y axis is oscillating about .140", back and forth; release F1 (up now), no change; click F2 (down now) both axis stop motion, you can turn motor shaft and move DRO the correct way.

Drive settings: X axis, SW1-6=on (if this is other way motor will still run away, and Red LED will be on drive)
Y axis, SW1-6=off (if this is other way motor will still run away)

The attached wiring diagram was used as reference during wiring. The address of TB5 is 1=ENAO-; 2=ENAO+; 3=GND; & 4=AOUTO. This is not included diagram. Does diagram look ok?

many thanks, for all the continued support.

Edit: The diagram shows no lead from P1-11 GND (Signal Ground) and (Location 3) GND on TB3. Should there be?