Very strange behavior, CoreXY with external drivers

[Capricorn]

@dc42

to clarify how my extern drivers are connected:
all Step+/Dir+ from the ext. drivers go to +5V.
all Step-/Dir- from the ext. drivers go to the corresponding pins on the breakout board

[dc42]

@capricorn said in Very strange behavior, CoreXY with external drivers:

@dc42

to clarify how my extern drivers are connected:
all Step+/Dir+ from the ext. drivers go to +5V.
all Step-/Dir- from the ext. drivers go to the corresponding pins on the breakout board

That sounds good.

Are you using G1 S2 moves (after sending G91 to select relative axis coordinates) to test the motors individually?

[Capricorn]

@dc42

yes, i did, x and z go together and i can´t find a shortcut...
i also tried to redirect z to drive 8 or 9. Same behavior...

[dc42]

1. Do any other motors move when you command the Y motor?

2. Please check that you really do have +5V on the common 5V feed to the + inputs of the stepper drivers.

[Capricorn]

@dc42

no other motors affected by moving Y.
the Voltage at the + inputs of the drivers is 4.56 V

[Capricorn]

@dc42

meanwhile i tested another driver for z-motor (have more of them as spare) and also testet to set the
config to cartesian kinematiks. No luck, always x/z move together.... I´m frustrated....

[Capricorn]

@veti

thank you, for your help, i´m just about cabling the printer. i can test it, when everything else is running.

[dc42]

Are you sure that the power to your external stepper drivers is stable? I am wondering whether when they are driving the motors, the voltage could be dropping.

[Capricorn]

@dc42

i test that... but i think so, cause i serve 5V to the board with a extern 50W power supply

[Capricorn]

@dc42

testet, konstant 4.45V. I take the 5V from the breakout board. Should i take it from the main board?
Or direct of the power supply?

[dc42]

@capricorn, I mean the main power to your external stepper drivers - 12V, 24V, 36V or whatever you are using.

[Veti]

@capricorn said in Very strange behavior, CoreXY with external drivers:

i test that... but i think so, cause i serve 5V to the board with a extern 50W power supply

how do you wire the two power supplies? i think the negative needs to be connected between the two, but i am not 100% sure.

[Capricorn]

@dc42

konstant 41V motors driving , i´m using a 600W power supply

[Veti]

i dont think 41v is supported

https://duet3d.dozuki.com/Wiki/Choosing_the_power_supply

The Duet 2 (Wifi and Ethernet) work with a VIN supply of between 11V and 25V

[Capricorn]

@veti
i don´t think so....

[Capricorn]

@veti

this is the power for the external motor drivers, not to the duet2

[Veti]

@capricorn

please draw a diagram. this is getting confusing.

including all power supplies and the wires between them.

[Capricorn]

@veti
that´s easy.

12V and 5V go to the duet2
41V go to the external motor drivers

[Veti]

and how are the power supplies connected to each other?

[Capricorn]

@veti

this are 3 different power supplies. one end each to 220V the other end to the 5v/12v input duet2 and 41v to the motor drivers. No direct connection (except 220V) between them.