# moving problem

09 Oct 2019 07:11 - 09 Oct 2019 07:34 #147538 by phillc54
Replied by phillc54 on topic moving problem
A couple of rules of thumb I have used:

Current should not exceed the motors rated current.

Motor supply voltage maximum = 32 * SQRT(motor_inductance)

The following user(s) said Thank You: RoberCNC

09 Oct 2019 07:39 #147539 by RoberCNC
Replied by RoberCNC on topic moving problem
Technical Specifications

Part No.: 23HS9430B
Frame Size: NEMA23
Phase: 2 Phase
Step Angle: 1.8 degree
Current: 3 A
Rated Voltage: 4.8V
Resistance: 1.6Ohm/phase
Inductance: 6.8 mH/phase
Holding torque: 425 oz-in (2.8N.m)
Detent torque: 12N.cm
Rotor inertia: 800 g.cm²
Weight: 1.7 kg
Length: 112 mm

this would be the datasheet of my steppers, according to what you say I should not exceed 3A (in RMS), which I comply with, and the maximum voltage would be 6.8 * 32 = 217.6, the latter is not very clear to me

09 Oct 2019 08:00 #147541 by Clive S
Replied by Clive S on topic moving problem
Rob those motors are quite high inductance I usually buy 8 wire motors nema23 that are wired in parallel that have 3.2mH at 4.2A

The voltage is down to the drives you have ie if they are 50v drives then you can go to about 36v on 80v drives i generally use them at about 68V without issue
The following user(s) said Thank You: tommylight

09 Oct 2019 08:01 #147542 by phillc54
Replied by phillc54 on topic moving problem
32 × sqrt(6.8) = 83.44579079

So your max motor supply would be 83V or you drivers rated max voltage, whichever is lowest.

09 Oct 2019 08:25 #147544 by RoberCNC
Replied by RoberCNC on topic moving problem

Rob those motors are quite high inductance I usually buy 8 wire motors nema23 that are wired in parallel that have 3.2mH at 4.2A

The voltage is down to the drives you have ie if they are 50v drives then you can go to about 36v on 80v drives i generally use them at about 68V without issue

I write down that information, thank you very much, it is a fact that I did not know and important for me in the future.

Thanks to you too Phill, I just deduced that sqrt is square root. All this leads me to what fellow Rodw and Tommy had told me, but I wanted to know a little more about where the numbers come from, to gain knowledge, thank you very much dudes.
The following user(s) said Thank You: tommylight

20 Oct 2019 11:40 #148403 by RoberCNC
Replied by RoberCNC on topic moving problem
Hello everyone.
While I'm waiting for the power supply I'm making improvements, one of them is to implement an Xbox joypad as a pendant following the Big John manual and of course, I have problems, hahahaha, but before asking for help I wanted to ask if it is correct to do it in this thread or if I should send it somewhere else. Thank you.

20 Oct 2019 22:03 #148436 by phillc54
Replied by phillc54 on topic moving problem
If it is an unrelated issue it is probably best to find a section in the forum that the new issue relates to and begin a new thread.
The following user(s) said Thank You: RoberCNC

02 Sep 2020 17:13 #180449 by RoberCNC
Replied by RoberCNC on topic moving problem
Hello partners.

I wanted to thank all of you for the help provided throughout this thread, time has passed already, between some things and others, but finally to tell you that you were right. I went back to the subject of the machine with higher voltage sources for each driver (up to 80v) and I even managed to reach absurd speeds hahahaha.

I just wanted to put it on record in case it could be of help to someone in the future by ending this episode and thanking you all for the time, patience and help you have given.

Rober.
The following user(s) said Thank You: tommylight