New Eagle Conversion

If the drives drift when LinuxCNC is not powered you have a dangerous situation
This means you do not have the drive enables properly controlled by LinuxCNC

I would fix this before proceeding further

Hi Peter,
The servos did not drift when linuxcnc is disengaged. They were balanced when I pulled it from the Anilam. I was just answering that I could zero when engaged, I fully expected I could; but then it is not balanced when disengaged. I will leave it balanced for disengaged as I don't want it to drift when linuxcnc is disengaged. Is there any way to set an offset for the 7i77 when it is suppose to be idle? And I did a lot more checking. I get that 7.3 mv offset even when it is not plugged into the servos.

Do you have an idea about the ferror I've posted?

Thanks, Dan.

again:

If the drives drift when LinuxCNC is not powered you have a dangerous situation
This means you do not have the drive enables properly controlled by LinuxCNC

The drives MUST be disabled before LinuxCNC starts and is in the Machine-on state

If you have any state where the drives continually drift, this mean the drives are enabled but
the feedback loop is not in control. This should NEVER happen and indicates a dangerous condition

Hi Tom, Peter,
There is no drift. I created a drift because peter asked me to balance while the servo signal was active. I did and put it right back. The servos are not drifting. I'll unplug Y and Z and that puts me back to the ferror shown on the hal scope. In the end I'll switch the servo power from F2 if the offset from the modulators can not be balanced. The servo rack has no other way to disable the drives, it is all or non.

The only possible way to control the servos seperatly would be to hack the rack and bring out the limit sense from the drivers.
ServoDynamics_1525

Best, Dan.

So are you saying that the drives are disabled (and therefore cannot drift) when:
1. LinuxCNC is not running or computer off
2. When LinuxCNC is running but in the machine-off state

Hi Peter,
There is no disable other than to cut power to the amps. When LinuxCNC is in the off state or the computer is off, there is no drift with the amps powered. There never was drift right out of the box.

The drives enables _must_ be controlled by LinuxCNC as a safety issue

SD1525 drives have a active low disable ( pin 8 on the controller connector)
These should be grounded by a normally closed relay contact until linuxCNC is
controlling the motion

Hi Peter,
This is not wired on the rack. The Anilam just powered down the amps. I am planning to do the same.

OK then the drive power down must be controlled by LinuxCNC or it is not safe