Sudden dead stop while slewing


George Cushing
 

Not that fast. Yes, the regulator and the drivers have thermal protection. Forget whether the ESP32 does too. All the logic devices get power from the regulator. If you don't lose alignment it's not the regulator. Then something else is cutting power to the motors.


Peter Boreland
 

@George I do not think it is thermal related. I can immediatly slew the scope again after the slew stops. No delay. Also the current reading while skewing at speed is relatively low, around 300mA per axis. Does the regulator recover that quickly, would not the whole Onstep controller shut down?

What mechanism is at play that stops the slew other than the regulator? I would assume the drivers, but it stops in both channels, not just the one. Bob, I've not found where I can read the SPI status info. Yes I have status enabled.   No whining from the motors, they run very quietly.  I was running at 24V but dropped down to 18V.  I put down the power supply down somewhere in the house and now cannot find it😖

Incidently, the slew rate of 7 degrees/sec is just an arbitrary limit. I see no reason, other than the sudden stop, for it not to go faster. I just need to change the config settings. Thinking 10 to 15 degrees/sec. Might be worth a video. This is testimony to the direct drive nema23 setup (motor directly driving my worms on my Losmandy G11).   I also got down to total 0.36" rms guiding error a couple of nights ago, so I'm confident in this setup delivering very high performance, all while carrying a 12" Newtonian plus associated imaging gear (75lbs or so).  I just love Onstep.

Peter


Robert Benward
 

Peter,
Is your SPI driver status enabled?  If it is, check the webserver for status info.  It might give you a clue as to what is happening.  7deg/sec is pretty fast, maybe you are getting a fault?  Are the motors whining or are they quite after they stop?  I would also go to 24V, if they are stalling or not meeting your current target, it might help.

Bob


George Cushing
 

Regulator thermal protection?


Peter Boreland
 

While slewing, I have recently experienced a sudden dead stop, usually about halfway to the target. Please, what might be happening here? Is it a current setting problem perhaps, or something else?

MaxESP32 Controller
TMC 5160 drivers
Slew rate 7 degrees/sec
Nema 23 motors direct worm drive.
Motor supply voltage 18VDC

Thanks,

Peter