Problems with Z axis steppers

zapta

@yagodajm said in Problems with Z axis steppers:

12V Rated Current : 0.4A Resistance Per Phase : 30Ω±10%

This stepper doesn't look as a good fit for 12V system with two steppers in series. You want a lower resistance and higher current stepper (ignore that voltage specification of the stepper, it doesn't matter).

Let's see if anybody here will come with a recommendation for a stepper.

aidar

Until you get better steppers, you can try to connect second Z motor to E1 (and of corse config it properly), that way they are not connected in series at least.

yagodajm

Do you have any recommended steppers to use with the duet maestro?

yagodajm

Do either of these work? I am thinking the first one because of the current rating on the duet maestro.

Nema 17 stepper motor with step angle 1.8deg
Holding Torque: 45Ncm(63.74oz.in), 12-24 VDC
Rated Current/phase: 1.50A & Phase Resistance: 2.3ohms

Motor Type: Bipolar Stepper

Step Angle: 1.8 deg.
Holding Torque: 59Ncm(83.6oz.in)
Rated Current/phase: 2.0A
Phase Resistance: 1.4ohms
Inductance: 3.0mH+/-20%(1KHz)

If I use these, do I still need to switch power supplies to 24 v ?

Thanks,
Justin

zapta

@yagodajm, the spec of this 1.4OHM stepper looks much better. Let's see what they expert here say regarding 12V vs 24V.

There are stepper motor calculators. E.g. this one.

https://www.allaboutcircuits.com/tools/stepper-motor-calculator/

yagodajm

@zapta
I am just worried with the current on the second one. The maestro Max's out at 1.6, I believe it is to much?

Phaedrux

Those motors would be a better fit. The rated current is ok for the maestro as you'd be using 70-85% of rated current.

24v is always better choice than 12v if possible, but keep in mind that requires 24v heater and fans (though fans you can use a buck converter to provide 12v).

yagodajm

Everyone, thanks for all of your help, I went a head and ordered the

Motor Type: Bipolar Stepper

Step Angle: 1.8 deg.
Holding Torque: 59Ncm(83.6oz.in)
Rated Current/phase: 2.0A
Phase Resistance: 1.4ohms
Inductance: 3.0mH+/-20%(1KHz)

At what ma should I run them at, around 1400ma?

thanks,
Justin

Phaedrux

1000 to 1400, but be sure to actively cool the board with a fan.

yagodajm

Got it, thanks for all of you help.

Karma

@yagodajm Partly Correct. It will be explained further down in this message.

The hotend part is a very easy part to replace. To save you some money, you can still use your 12V power supply to only power your 12V heatbed. That's until tou can get another heatbed that is 24V. Then again, some heatbeds are both 12V and 24V. It all depends on how you connect the heatbed. It will say that on the heatbed itself.

There is a way to use your 12V hotend with the 24V system. There is a command that will allow you to limit the amount of voltage to lets say, the hotend, the fans, the heatbed as well.

If you are interested with what I said above, just simple reply to my message.

Karma

Phaedrux

@Karma said in Problems with Z axis steppers:

There is a way to use your 12V hotend with the 24V system. There is a command that will allow you to limit the amount of voltage to lets say, the hotend, the fans, the heatbed as well.

Using PWM to "limit" the 24v power delivered to a 12v heater is not recommended. PWM means that it's just switching the power on and off very rapidly. So it's still getting 24v sent to a 12v heater, it's just off half the time. In a normal situation this can lead to premature heater failure. In a failure situation where full power is applied this is very dangerous. Not worth saving a few dollars.

Karma

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Karma

This post is deleted!

Karma

@Phaedrux What you said makes perfect sense sir. Please forgive me for doubting you.

This is something that person could use in a pinch, like for a very temporary amount of time.

I personally use the M106 S0.5 command just for my fans. I have a 24V system, I just couldn't find 24V noctua 40mm fan that was 24V. I really love these fans because they are almost silent when they are running. They are also very resilient when it comes to pushing out 24V to a 12V fan. That was when I was still learning the firmware and all. I was a Merlin guy at the start, then jumped to Repetier due to upgrading to a RADDS setup that didn't go anywhere for me. Always had problems with it.

I have a few DC Buck converters laying around here. I am not sure how they will respond to a variable input power. Like if they continue to try and push out 12V when there is only like 7V on the input side. I guess I have some homework to do.

Thanks for the lesson on this. I am very new to this firmware and the Duet3D 2 Wifi board. So far I love it. I wish I would have gotten the Duet3d 3 board. But I know my wife would kill me if I bought that right now.