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Creality Ender 3 Stock Factory Vref

Creality3D v1.1.2 stock vref values

A4988 Drivers
Vref set to ~90% of stepper rated current
Rs = 0.1ohm

X = 0,58v (0,725A)
Y = 0,58v (0,725A)
Z = 0,58v (0,725A)
E = 0,72v (0,900A)

Stepper Motor datasheets

Naming: [JK][S]HS[L]-[100][4]

JK: Manufacturer (jkongmotor) S: Size (42mm) HS: Hybrid Stepper L: Length (34/40mm) 100: Rated current 1.00 4: Number of wires

References

@3DSmitty

3DSmitty commented Dec 4, 2022

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@Avedena on my S1 the X and Y steppers were running hot as hell. I measured the vref and it was set to 1.189V for both, turned them down to your suggested 1.027V and they are still warm but not crazy hot. Thanks!

@sammcj

sammcj commented Apr 25, 2023

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Does anyone know what run current I should be using for the BJ42D09-20V02? (as found on the Creality Sprite extruder).

It says on their website that it's "0.6A", but I see someone above mentions 0.4 - which seems awfully low for an extruder motor.

@3DSmitty

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@sammcj On my S1 I measured the E vref on the pot is 0.934v, hope that helps.

@sammcj

sammcj commented Apr 28, 2023

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I managed to get hold of someone at Hunan Keli Motor Co who very helpfully shared this schematic with me for the BJ42D09-20V02 as used on the Creality Sprite extruder (found on the Ender 5 S1). Sharing here as it may be useful for others.

sprite-motor-BJ42D09-20V02

@Avedena according to these specs your table for the rate current for the BJ42D09-20V02 needs updating, resistance should be 1.75, current should be 0.84

@rohjaesung

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creality 회사의 bj42d15-26v12의 stepper motor 정격전압과 정격전류좀 알려주세요 몇 볼트일때 작동하는게 좋은지가 궁금해요 아무리 찾아봐도 안 나와요ㅜㅜ

@tripletto

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creality 회사의 bj42d15-26v12의 stepper motor 정격전압과 정격전류좀 알려주세요 몇 볼트일때 작동하는게 좋은지가 궁금해요 아무리 찾아봐도 안 나와요ㅜㅜ

Einen wunderschönen guten Tag.

Not very helpful, using you native language here isn't it?

@825i

825i commented Sep 8, 2023

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Please be considerate of others when posting here. Those of us with notifications really don't need distracting and otherwise pointless emails. Thanks.

@arshidkv12

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Can I use jk42hs40-1204a-02f for extruder?

@BloodyIron

BloodyIron commented Jan 18, 2024

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Anyone know anything about BJ42D09-0v03? I cannot find any source for this revision or data, and can only seem to get it from the "Creality Sprite Pro" package sources. I can't even find a spec sheet from any OEMs. I'm hoping to just replace a failed stepper motor from a more direct source, than paying the ~$100+ for other parts I don't need (in addition to the stepper motor).

@not-crazyramen

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Does anyone know if these currents are the RMS current or the true max? I'm finding conflicting info through google

@3DSmitty

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@not-crazyramen the currents listed on the blueprint are max currrent. To find the RMS divide the max current by 1.414. I run my Sprite extruder driven by TMC2209 UART at 600ma. Hope that helps.

@not-crazyramen

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@not-crazyramen the currents listed on the blueprint are max currrent. To find the RMS divide the max current by 1.414. I run my Sprite extruder driven by TMC2209 UART at 600ma. Hope that helps.

Yeah it does. Thanks! Do you know if that's the industry standard for "rated current?"

@3DSmitty

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@not-crazyramen the currents listed on the blueprint are max currrent. To find the RMS divide the max current by 1.414. I run my Sprite extruder driven by TMC2209 UART at 600ma. Hope that helps.

Yeah it does. Thanks! Do you know if that's the industry standard for "rated current?"

Not sure exactly how industry determines that.

@TDHofstetter

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@not-crazyramen the currents listed on the blueprint are max currrent. To find the RMS divide the max current by 1.414. I run my Sprite extruder driven by TMC2209 UART at 600ma. Hope that helps.

Yeah it does. Thanks! Do you know if that's the industry standard for "rated current?"

Not sure exactly how industry determines that.

The manufacturer decides what temperature the motor can tolerate continuously without degradation of the insulation on the motor's windings. They then determine how much current in 100% duty cycle stepping operation will raise the windings to that temperature.

That's the rated current.

Note that my explanation here is simplified a little.

@3DSmitty

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@not-crazyramen the currents listed on the blueprint are max currrent. To find the RMS divide the max current by 1.414. I run my Sprite extruder driven by TMC2209 UART at 600ma. Hope that helps.

Yeah it does. Thanks! Do you know if that's the industry standard for "rated current?"

Not sure exactly how industry determines that.

The manufacturer decides what temperature the motor can tolerate continuously without degradation of the insulation on the motor's windings. They then determine how much current in 100% duty cycle stepping operation will raise the windings to that temperature.

That's the rated current.

Note that my explanation here is simplified a little.

On 3D printers it is usually set 80% of the rated current. Hope that helps.

@TDHofstetter

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I can't speak to "usually". It's often as high as 90%, and it can be set much lower to save a little power if you aren't running a race printer. Feel free to adjust it downward until your printer starts losing steps, then back up until the step loss disappears.

Then pop a note into the control board compartment to remind yourself of that adjustment in case you ever get the Need for Speed and want to adjust it higher again.

@jamincollins

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@MaxMishchenko any chance you can reach out to your contact and see if they have details for the BJ42D15-26v12?

@PaulW

PaulW commented Oct 11, 2024

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@MaxMishchenko any chance you can reach out to your contact and see if they have details for the BJ42D15-26v12?

I've specs Here for both BJ42D15-26V12 and BJ42D15-26V19 (This is the same spec as the BJ42D15-26V02 hence drawing ID matching)

@wolfie24

wolfie24 commented Nov 9, 2024

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@not-crazyramen the currents listed on the blueprint are max currrent. To find the RMS divide the max current by 1.414. I run my Sprite extruder driven by TMC2209 UART at 600ma. Hope that helps.

Hi pal. It´s correct divide by 1.414. Is not multiplicate by 0,707 for RMS Value?

@kdkwarhead

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@not-crazyramen the currents listed on the blueprint are max currrent. To find the RMS divide the max current by 1.414. I run my Sprite extruder driven by TMC2209 UART at 600ma. Hope that helps.

Hi pal. It´s correct divide by 1.414. Is not multiplicate by 0,707 for RMS Value?

It’s the same thing…
1A/1.414=0.707A
1A*0.707=0.707A

@wolfie24

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Hi. I think you're wrong pal. I remember the electronic classroom in the first year and say0.707. i find this:

How to calculate RMS value of current?

Then, the RMS voltage (VRMS) of a sinusoidal waveform is determined by multiplying the peak voltage value by 0.7071, which is equal to one divided by the square root of two (1 / √2)

@kdkwarhead

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Dividing something with 1.414 is the same as multiplying something with 0.707. I’m not smart enough to see what the problem is. Hopefully some one else can help you.

@Awesten3D

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Anyone familiar with the first version of the Sprite extruder that just screws on to a stock ender 3 x-gantry plate? BJ42D09-20V01 model number on stepper. Can't find anything on it. I'm running it at .8a, still cool to the touch tho so I'm hoping the documents here apply?
1000001520
1000001544

@stablestud

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Since this thread is now kind of a database for all sorts of stepper motors, I'm also adding these for reference for others. I have those on my Ender 3 Max. I got the datasheets directly from the manufacturer Kelimotor by asking the sale assistant.

BJ42D16-26V09 -> apparently the same as BJ42D15-26V09
BJ42D15-26V09
BJ42D15-26V09 drawing
BJ42D15-26V12
BJ42D15-26V12 drawing
BJ42D22-23V01
BJ42D22-23V01 drawing

@mdsitton

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https://drive.google.com/file/d/10bUmRyaTjHy4UPEDfP2xxpU4MgqT2sci/view?usp=sharing

Here is the BJ42D15-26V10 that i got from them, seems like the actual motor specs are the same as most of these so far.

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