Help please. Dip switches and mach 3 settings

[Radu_Andrei]

Probably a adapted translation would have pointet out better the initial assumption that a father is teaching his child to walk for the first time, and the pun, that actualy he.s son was just drunk, and faced the same challenges as a toddler.

Non verbal humor tends to work best for an international audience. Mr Bean, Charlie Chaplin, Benny Hill etc

Here.s not the place for that. We.ll stick to technical discussions.

Although, magiciner, I would be glad if you would post a link with the type of jokes and humor appreciated by yourself. Just to have a read, without bothering any admin by posting random unrelated topics.

We.ll get back with the cnc progress soon, as it takes a bit of time to implement Rob.s instructions.

[Radu_Andrei]

Hi again.
Just to test to see if it improves anything, I used some zinc sheet metal to shield the control box.
Earthed and everything, it did not make much difference.
So I started to disconnect components, and removed the vfd from his own shielded box, and then unplugged the limit switches fom the breakout board, and all was left was the pc with the drivers, sources and steppers.
The steppers are earthed at the driver end, everything at a star point as recommended. Checked all shield with the multimeter, and it.s all good.

The only thing done questionable is that I have one stepper cable, which I measured wrong, and had to join it to another bit, each of the 4 wires twisted and taped, and did the same with the shield, put some aluminium foil on top, and taped all over it. Not great, but it should not be a bigger deal than any other type of connection.
Also the limit switches are the cheap lever type. Even if not the best, they are not connected to anything now, and still have issues.

I removed all flexible couplings, and have the motors running without any load.

THE PROBLEM: randomly, the motors stall, all 3 of them, some a more often than others. Simply keeping pressed the keyboard arrow keys, they run ok, for 5, 10 even 30 seconds, then at least one stalls.
I,ve loaded a default g code, those coming with the software, and the same problem. I changed the motor turning config to acc 50 and speed 300, 400, 500, still have the problem.

I.ll remove all steppers tomorrow and connect them directly to the drivers. At least to exclude the cables as well.

The motors are 5.6A and the drivers set to 4.9A Peak, 3.5A RMS.
The drivers are DQ860MA and wired like this: +5v to PUL +(+5v), and bridged to DIR+ and ENBL+, then PULL- and DIR- go to the pins 2 and 3 for example on the BoB, ENBL- is not wired. The other 6 terminals are 2 for the source and 4 for the stepper.
The breakout board is db 25-1205.

I.m working on the metal cases, control box and vfd box, suggested by Rob and Clive, but I can not go further with the design and construction, until I figure out the cause of this stall.
I.ve already tried to separate the components and to shield all boxes and ground them. I rechecked all wires, including the drivers, and rewired those with twisted cables inside the control box. This wires between the sources and drivers and the BoB are not shielded. Everything else is.
I had a touch plate fitted and disconnected it as well, as it concerned me that the wire connected to the spindle, and to the chasis as is all conductive materials, sends a ground signal into the input pin of the BoB and might cause problems. Does it?


I.ll even remove tomorrow all other wires from the drag chain and leave only the steppers. It might exclude something else.

BUT I higly suspect the BoB.
What do you think guys? What am I missing?

[Clive S]

I am sorry you seem to have all these problems but keep at it as it will be worth it in the end.

What power supply are you using for the drives?

[Radu_Andrei]

the ones that came with the kit, individual for each motor
S-350-60 +60V 5.85A

[Clive S]

the ones that came with the kit, individual for each motor
S-350-60 +60V 5.85A

60V is a bit low for nema 34 but you will be limited with the drives you have.

What micro step rate do you have the drives set at. And what max velocity are you using in Mach (under motor tuning)

This might just be the cause that you are trying to turn the motor too fast

[Radu_Andrei]

Dip switches set as OFF OFF ON ON OFF ON ON OFF , which sets the thing to 4.9A Peak, 3.5A RMS, Full Current from SW4 (i don,t really know how to set this), and 2000 pulse/rev. The next current setting is 5.7A peak.

Nema 34 motor 5.6A, 1200oz-in, and driver DQ860MA.

motor turning: acc at 50 velocity at 300 for the y axis (whole gantry), cause at a full stop, it does not shake the whole thing, and 400-500 velocity for the x, seems to not cause trouble.

I took apart the whole thing, and have it on my desk right now. I connected one stepper only directly to the driver and it works ok, but still it seems to lose a few steps here and there, at various speeds.

I.ll use it next with the long shielded cables and see how it works.
Will post some results, photos, videos soon.

[Clive S]

Dip switches set as OFF OFF ON ON OFF ON ON OFF , which sets the thing to 4.9A Peak, 3.5A RMS, Full Current from SW4 (i don,t really know how to set this), and 2000 pulse/rev. The next current setting is 5.7A peak.

This might be to high try sw 5,6,7,8 set to off/on/on/on = 800 p/rev set sw 4 to off = half current when idle

setting the above will alter the distance travelled but that can be sorted later when you get the motors working