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Once your EtherCAT master is working you will need:

1.) LinuxCNC EtherCAT:
github.com/linuxcnc-ethercat/linuxcnc-ethercat

2.) For CiA402 drives:
github.com/dbraun1981/hal-cia402

Some servo drives have native support in linuxcnc-ethercat.

Take a look at the linuxcnc-ethercat documentation - which also includes example ethercat-config.xml files.

I was suggesting wiring the encoder directly to the 7C81 pins
on a different 7C81 connector than the BOB.

(with series 100 Ohm resistors for protection from negative voltage spikes)

Thanks for your reply. But the cheap Chinese boards require 24v power supply to energize its inputs. So inputs are all not responding to 5v input of the encoder. Kindly help as how to wire the 5v inputs with 7c81.

How can i Check this fault status ?
this way ?

What is the omronmx2 fault status?
 

You should be able to use single ended encoder pins directly with a 5V encoder.
The 5abobx3d configuration has encoders on all connectors and the 5abobx2
configuration has encoders on both connectors.

For more input protection, I  would add a say 100 ohm series resistor
to the encoder signal lines.
 

I would try using the latest mesaflash:

github.com/LinuxCNC/mesaflash

As there were some bugs with the 7I90 name

( build instructions on bottom of page )


 

 


 
 

Hakan wrote:

It can be that the motor speed needs to be ramped up, like it is by linuxcnc.
Setting 6000 rpm as a step is quite challenging.
Anyway, 3000 rpm is more than decent for a stepper motor.

Consider to use csp mode, that's what most people do.
The position feedback is lagging two servo cycles when using ethercat
and a velocity loop has a hard time.

If you use csp, the position update will stop in your scenario, and the motors will stop.
Check out the SDO listing, there is a max current setting (per motor).

 

If I got my math correct, target velocity 500000 = 3000rpm, target velocity 600000 = 3600rpm

>needs to be ramped up...
Yes, another detail I failed to remark on: I noticed when operating in opmode 9 this drive uses a sane accel/decel rate, which kind of surprised me.
I can change target velocity in big jumps and it ramps smoothly to my target velocity. But if I set controlword = 6, the addressed motor stops BAM!
If I set target velocity first, then controlword = 15, it does not move. I changed target velocity to 0 then to 10000 then it started. Didn't check whether I actually had to set target velocity = 0 first.

As far as I can tell, in opmode 8, it behaves as you described. If I set position in any size of small or big jump, it tries to move there instantaneously. Small jumps move the motor, big jumps just make a "chirp".

>If you use csp,
Good idea. I just had to play with my new toy.

rodw wrote:

Its interesting your feedback about motor performance. I di wonder about how I would go not using Lichuan motors. 3000 rpm is up where I was expecting!

 

I know the motor's phase inductance or voltage rating can make a huge difference in top speed attainable. These motors do not have either of those specs listed, making it harder to compare specs, but when I get a chance, I'll try to measure phase inductance.

Higher inductance motors need higher voltage to produce the same speed and torque. This is the first thing that comes to mind, seeing what these motors can do.

Frankly, I'm quite impressed I got this kind of speed out of them. They must have relatively low phase inductance. They're labelled hybrid stepper motors. I'll hazard a guess they're wound to similar specs as a BLDC motor, but in 2 phase configuration. Its been a while since I messed with steppers, the ones I previously used would never have got this speed on 24V, hardly even at 48V.

I was thinking that the best option would be to use an MPG WHB04B? Is the wireless or wired version better? Can everything be controlled from the MPG, including the start/stop spindle?

Hi, 

Please can you share a bit file where i can use 5v encoder inputs on my bob P7 for my 7c81 board. I donot want to use 24v but 5v as a quad encoder fast inputs. Rest pins are fine for a normal 5axis bob3 pins.

thanks

Maybe i almost got it. Now i have this error -> see picture 

HI Pcw
Can you please provide a bit file for the following

7i92+7i76+7i89

Thanks
Henk

You just named them "statusword" instead of "cia-statusword" in the ethercat-conf.xml file.
It is often worthwhile to examine the words it complains about.