External driver and Duet 1XD issues

[droftarts]

@p_vnct Did you reconnect the enable wires, and that part is working?

Ian

[p_vnct]

@droftarts No i didn't !

[dc42]

@p_vnct said in External driver and Duet 1XD issues:

I had also to remove M92 for the U axis and modify the R parameter to R1 in M569 to get it work.

That should only matter if you connected the Enable wires.

@p_vnct said in External driver and Duet 1XD issues:

it is working now with T5:5:10:10 for timings.

According to the data sheet, it should work with 2.5:2.5:5:0. What wiring scheme did you use between the 1XD and the driver?

[p_vnct]

@dc42

About the R parameter, you are right this should matter only with the Enable wires, but with R1 and the enable wires connected it didn't work.

I used the differential wiring without the enable wires and if i go 2.5:2.5:5:0 timing values it does not work anymore.

[dc42]

@p_vnct said in External driver and Duet 1XD issues:

I used the differential wiring without the enable wires and if i go 2.5:2.5:5:0 timing values it does not work anymore.

In that case, it appears that the driver isn't meeting its specification. Just to check, if you set 2.5:2.5:5:5 and then send M569 P122.0 with no other parameters, what timing does it report? The first figure should be quite accurate, but the other figures will be rounded up to the next available value.

[p_vnct]

@dc42 Late response apologies !

M569 reports 2.7:2.7:2.7:2.7.
but when i enter this values the motor do not move anymore.

I have worked down to T4:4:4:4 and the stepper moves.

But i have a feeling that something lower the torque of the motor.
Indeed the nema 34 is rated 13Nm under 60v @ 2000steps/rev.

But i clearly do not have this torque available, what could influence the torque in the duet settings ? i guess not very much as this is related to the external driver, right ?

[jay_s_uk]

@p_vnct said in External driver and Duet 1XD issues:

i guess not very much as this is related to the external driver, right ?

correct

[dc42]

@p_vnct said in External driver and Duet 1XD issues:

But i have a feeling that something lower the torque of the motor.
Indeed the nema 34 is rated 13Nm under 60v @ 2000steps/rev.

The torque is determined by the motor current, which is set by your external driver. Most external drivers have switches to set the current.

btw the 6HC can drive many Nema 34 motors directly, without the need for an external driver.

[p_vnct]

@dc42

actually i drive a nema 34 from another Duet 6HC on another similar printer . but found that i do not use the entire torque of the nema as the Duet is "limited" to 36v and 4A.

As this Nema 34 is used for a pellet extruder, i am currently trying to drive it (on my second upgraded pellet printer) with the external driver set up at 6A-7.2A peak on 60V to see if i can achieve better flowrate and without a planetary gearbox.

For now without the planetary gearbox i cannot extrude at an acceptable flowrate with the external driver nor the drivers on the 6HC.

I'll try with a planetary gearbox like my first printer but with the external driver and see if i get better results with it.

Another thing i quickly tried but without success is to set up a second extruder motor but drived from the 6HC.
I think i don't have the right syntax for that.

Because if i map :

M584 E122.0:0.4

Then what should i set in :

M350 E??:16 I1       
M92 E??:100           
M906 E??:1000 I30    

As if i understand correctly those values are now set on the external driver ?

[p_vnct]

@p_vnct

i Have tried :

M584 E122.0:0.4
M350 E1:16 I1
M92 E14.00:100.00
M906 E0:1500 I30

Motor on external driver is working but not the second one, even if the duet report it moving.

EDIT: my bad , i just forgot to add the drive to M563... now it is working

[dc42]

@p_vnct thanks, I'll mark this as solved then.