Encoder feedback 7i77 sensor magnetic BALLUFF

Hello everyone

I am using the 7i77 electronic board with the analog output AOUT1 connected to an analog drive on the Z axis.

The Z axis is the part that moves the punch of a punching machine.

This punch makes a downward movement with up to -10 volts and an upward movement with +10 volts. This movement perforates the metal sheet.

This Z axis of the machine has a magnetic sensor that detects the movement of the Z axis.

This sensor has an output connected to the INPUT0 input of the 7i77 electronic board that shows when the Z axis is moving upward.

The voltages of this magnetic sensor on the Z axis have a high limit of 10V, when the Z axis is moving downward the low limit is 0V.

Does anyone know how to configure the HAL configuration of LinuxCNC so that the 7i77 electronic board recognizes an analog input as feedback from the Z axis movement encoder?

magnetic sensor technical data:

BALLUFF  magnetic sensor BTL5-A11-M0060-P-SA224-KA02

Recordable speed, max. 10 m/s

Repeatability accuracy ± 10 µm

output voltage 0 ... 10 V


link   publications.balluff.com/pdfengine/pdf?i...anguage=pt&type=kmat


Does anyone know how to configure the HAL configuration of LinuxCNC so that the 7i77 electronic board recognizes an analog input as feedback from the Z axis movement encoder?

2 options I can think of would be to add either
a 7I87 (8 channel  sserial analog +-10V input card)
or a THCAD2 (0 to 10V voltage to frequency card)

The THCAD2 frequency would be read by a encoder input

 

Thank you very much for your reply. I will arrange to purchase the THCAD2. Just a few more questions, please:

( 1 ) - Are the electrical connections between the THCAD2 and 7i77 electronic boards: FOUT+ with QA0, FOUT- with /QA0, +5V with +5V, and GND with GND of TB3 of the 7i77?

( 2 ) – Since the QB0, /QB0, IDX0, and /IDX0 connections of the TB3 connector of the 7i77 will be left without any connection, do I need to update it so that the 7i77 recognizes only the A signal channel?

( 3 ) – Is there an update for my configuration that allows the 7i96s + 7i77 to recognize the THCAD2 as the Z axis encoder?

1. Thats correct

2. You need to set the encoder in counter mode

3. Yes, you need to use the encoder velocity signal as the feedback source
for the Z axis position loop, you may also need to offset and scale the feedback
because the THCAD2 has an inherent offset (since it has an about 100 KHz signal
at 0V)

Thank you
Do you have any examples of how to move and scale the feedback?
I'm trying to use the 7i77 analog port but it displays an error message calculating movement on axis 2 (Z). Could this error be the reason for moving and scaling the feedback?
Please, where can I find examples of this?
Please tell me the reason for the error below?movement calculation error on axis 2 ( Z )



File HAL



File INI




HAL 

# ---Encoder feedback signals/setup---



#net z-pos-fb               <=  hm2_7i96s.0.7i77.0.0.enc0.position
net z-pos-fb               <=  hm2_7i96s.0.7i77.0.0.analogin0
net z-pos-fb               =>  joint.2.motor-pos-fb
net z-index-enable    joint.2.index-enable  <=>  hm2_7i96s.0.7i77.0.0.enc0.index-enable
net z-pos-rawcounts        <=  hm2_7i96s.0.7i77.0.0.enc0.rawcounts


INI

[AXIS_Z]
MAX_VELOCITY = 25.0
MAX_ACCELERATION = 750.0
MIN_LIMIT = -100.0
MAX_LIMIT = 0.01

[JOINT_2]
TYPE = LINEAR
HOME = 0.0
FERROR = 10.0
MIN_FERROR = 1.0
MAX_VELOCITY = 25.0
MAX_ACCELERATION = 750.0
P = 50.0
I = 0.0
D = 0.0
FF0 = 0.0
FF1 = 1.0
FF2 = 0.0
BIAS = 0.0
DEADBAND = 0.0
MAX_OUTPUT = 0.0
ENCODER_SCALE = 1.0
OUTPUT_SCALE = 10.0
OUTPUT_MIN_LIMIT = -10.0
OUTPUT_MAX_LIMIT = 10.0
MIN_LIMIT = -100.0
MAX_LIMIT = 0.01
HOME_OFFSET = 0.0
 

is that a following error?

If so that may be expected before tuning or even determining
if the feedback is in the proper direction. (expect runaways!)

You likely need to widen the following error limits in any case