EBB42 CAN and Nema14 stepper heating problem

General Discussion
1

Basic Information:

Printer Model: CoreXY
MCU / Printerboard: BTT SKR3, rasbperry pi5
TMC2209 driver BTT EBB42 CAN
Host / SBC
klippy.log

Fill out above information and in all cases attach your klippy.log file (use zip to compress it, if too big). Pasting your printer.cfg is not needed
Be sure to check our “Knowledge Base” Category first. Most relevant items, e.g. error messages, are covered there

Describe your issue:

Hi,
I have a heating problem about nema 14 extruder stepper motor with the BTT EBB42 CAN.
When I use the nema 14 extruder stepper motor direct connect BTT SKR3 board no problem but using with EBB42 CAN there is heating problem.

When I connect it via CAN, the engine does not warm up initially, but when I give the command (examp. M83 G1 E10 F600), it starts to warm up. Even if the engine is stopped, it continues to warm up.
Both connections, SKR3 and EBB42 are the same current, have the same configurations.
I would be very happy, if you help.
Thanks everybody.

klippy (3).log (2.5 MB)

2

Are you sure about this?

run_current = 0.300
hold_current = 0.500

Besides hold_current is not recommended to use, it should not be higher than run_current.

https://www.klipper3d.org/TMC_Drivers.html#prefer-to-not-specify-a-hold_current

Also 0.3 A for the extruder stepper is quite a bit low as long you have no gear.

Does the stepper driver has a heatsink?

Further info:

3

@EddyMI3D only so you can help him more; EBB boards use a TMC2209 driver, and a heatsink is provided but not installed.

1 Like
4

There is a heatsink in my stepper driver.

I disabled the hold_current value, but the result did not change.

I have previously tried many values such as 0.8, 1.22, 1.7 for the run_current value, but the result did not change. The stepper motor continued to warm up.

The problem occurs when EBB42 is used with CAN. Regardless of the run_current value, there is no heat problem in the stepper motor with SKR3.

5

Can you explain what you mean by “The stepper motor continued to warm up.”

How much does it warm up and why is it a problem?

When I look through your klippy.log I see a number of communications lost events. You do monitor the temperature of the EBB42 and the highest I see it reach is 37.C which should be fine.

When I look at your printer.cfg, I see that you have set your stepper_z and extruder [tmc2209... statements as:

[tmc2209 stepper_z]
uart_pin = PE1
run_current = 0.800
diag_pin = 

[tmc2209 extruder]
uart_pin = PC6
run_current = 0.300
hold_current = 0.500
diag_pin =

As was noted by @EddyMI3D the hold_current parameter shouldn’t be there but, personally, I’m more concerned about the lines:

diag_pin =

I’m not sure how Klipper will react upon encountering it - it’s not throwing an error but I’m not sure what it will do.

Based on the diag_pin lines, I’d be curious as to whether or not your Z Axis stepper is also getting “warm” when the printer is idle. If it is and the X and Y axis steppers aren’t then I would think those lines are the culprit.

Regardless, more information in terms of what you mean by “warm” and why it is a problem is required.

2 Likes
6

I’m uploading a new clippy file.

I turned off hold_current and diag_pin values.

I attached the heater bed sensor to the stepper motor so that you can monitor the temperature.
I have tried the run_current value before with values such as 1.22, 0.80, 1.7. But the heating problem of the stepper motor has not changed. The same problem occurred with different nema14 36mm round stepper motors.

The temperature value can reach up to 58-60 C degrees.

There is no heating in x, y and z stepper motors. Also, no EBB42 heating problem.

I think the problem is related to EBB42, but I cannot understand the reason.

Without the EBB42 Can board, it does not overheat at the same values as the SKR3 main board.

klippy (1).log (467.6 KB)

7

@Dentist
When this motor heating occurs, is the CAN bus wiring getting hot?

The +24V and Ground should be a wire gauge lager than CAN_L & CAN_H small gauge 24-28 gauge.

The manual for EBB42 V1.x states 12-24V 9 Amps, both power wires (+ & -) would need conductors that could handle this plus 10% to be safe.

8

In your klippy.log, you have defined the extruder using the statements:

[extruder]
step_pin = EBB: PD0
dir_pin = EBB: PD1
enable_pin = !EBB: PD2
microsteps = 16
rotation_distance = 7.32
full_steps_per_rotation = 200
nozzle_diameter = 0.400
filament_diameter = 1.750
heater_pin = EBB: PB13
sensor_type = EPCOS 100K B57560G104F
sensor_pin = EBB: PA3
min_temp = 0
max_temp = 260
control = pid
pid_kp = 26.447
pid_ki = 1.560
pid_kd = 112.070

:

[tmc2209 extruder]
uart_pin = PC6
run_current = 0.800

Shouldn’t the “uart_pin” line be:

uart_pin = EBB:PA15

“PC6” will be on the SKR board, NOT on the EBB42.

Let me know how that works.

1 Like
9

There is no temperature increase in the CAN bus cable.

When the system is turned on, there is no heat increase in the stepper motor.

But, when the stepper motor starts to move, the temperature begins to increase. Even if the stepper motor stops, the temperature increase continues.

10

Have you tried it with a different stepper motor?

11

Yes,
I tried tree different steper motor and two different tmc2209 driver.

12

Yes, you are right. I forgot to change the Uart pin to EBB.
The new values are as follows:

[tmc2209 extruder]
uart_pin: EBB: PA15
run_current: 0.800

But the heating problem continues.

13

It also can be a issue with the board itself.

1 Like
14

EBB42?
You may be right.
I think so too.
Because, when you connect it directly to SKR3 with the same current settings, there is no problem.

1 Like
15

If you’ve fixed that then, as @EddyMI3D suggests, try another EBB42.

Just out of curiosity, when the stepper “warms up” can its shaft be turned or is it locked in place?

16

I want to confirm this - you are plugging in the extruder stepper motor that is heating up into the SKR into a stepper port with the driver set up and it’s not heating up? That means you are taking apart your toolhead (where I presume the stepper and EBB42 is located) and physically removing the stepper and plugging it into the SKR. Correct?

What happens if you plug in another stepper (ideally one that isn’t heating up) into the EBB42?

Have you done any prints with things in this configuration (ie heating up) and what is the quality of the material laying down? Does the extrusion stepper “click” or “bang” when you are printing?

I’m asking because we’ve talked through the EBB42 at length but not discussed the stepper at all. When I had my original Voron 2.4 with the stepper in the toolhead and no toolhead controller, the stepper wires were a metre or so long. When I have a stepper motor connected to a toolhead controller, I cut them down to 2-4cm. I would expect testing the stepper on a port in your printer to be a major undertaking.

Could you send some pictures of your toolhead and the stepper in question (with its wiring displayed)?

What you’re describing is hard to reconcile with how things are supposed to work and I don’t think we’re asking all the right questions first to get at what the problem is.

17

What exact Nema14 motor is used on the extruder port?
Maybe even the 0.8 A are too much.

Double check the TMC chip on the EBB42 though default should be a TMC2209. However it might be good to specify the correct sense_resistor value from the datasheet in the [tmc2209 extruder] section.
Wrong values can drive too much current to the motor.

Can you take a photo of the top side of the EBB42 with all the wiring?

And does the Nema14 motor work except for the heat?

18

@LifeOfBrian’s comment made me think of something just now and this is totally anecdotal.

I’ve been messing with my Voron 0.2 this weekend (it’s my secondary not often used printer) and while getting it back in working order I realized my extruder stepper was getting HOT.

Not too hot too touch, but pushing that limit, hotter than I would have expected.
My run current is set at .85 so I dropped it to .8 and then I started having extruder issues and skipping.

This is just some knock off NEMA 14 Pancake stepper, but some definitely run hotter than others.

@Dentist

The temperature value can reach up to 58-60 C degrees.

I went to the site below and pulled the datasheet on a few of their different motors.

and they all say the same thing:

image

They’re rated for an 80c rise ABOVE ambient with a max temp of 130c before the insulation starts melting.

So 58-60c isn’t unheard of and falls under their rated temp rise.

1 Like
19

My printer is not finished yet.
I’m testing the hardware parts. I can use to replace EBB42 and SKR3 motherboards with the same stepper motor cable. (changin the printer.cfg pin settings)
So motherboard and toolhead are on the table. I dont taking apart everytime :slight_smile:

I tried tree different nema 14 stepper motor

NEMA14 Pancake Type Motor
36BYGH 36HS2418CL16
Step angle: 1.8±5% /STEP
Current: 1.88A/PHASE
Number of teeth: 10 teeth

Nema14
Nema14980×627 377 KB

20

Well, I think I found a datasheet for that Stepper.

image
image883×713 105 KB

Looks like it’s rated for 80 Kelvin, So as long as you don’t exceed -193.2C you should be fine.

Just kidding, Apparently “K” is winding temperature rise, that’s not confusing or conflicting with other measurement systems at all.

But again, That Stepper is also rated for 80c above AMBIENT.
Insulation class B is rated at 130c max.