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Video Update! Power Supply Issue? Motors only studder when Extruder and Heat bed are on

Posted by XYZM 
GEEetech is sending me a new power supply because of this issue.

Under manual control in Repetier-Host V.090D I can smoothly control all my axes, but once I click heat extruder, it worsens, when I also click heat print bed. it really worsens.

My Vrefs are

X 1.57v Moves the smoothest with both on(heat Bed and extruder), but still studders

Y 1.51v Does not move at all with both on

Z 2.17v Shudders alot with both on

E1 1.89v

E2 2.51v but I don't have an Extruder 2


This is using the GT2560 board.

Its a Prusa i3 by Geeetech


Wondering if anyone has had this issue?

[www.youtube.com]

Edited 1 time(s). Last edit at 06/02/2015 08:24PM by XYZM.
Re: Power Supply Issue? Motors only studder when Extruder and Heat bed are on
June 01, 2015 11:44AM
When I disconnect the Heatbed, I get it to print, but it jitters so much, it pretty much missed the first layer of the box.

Is it really the power supply??

Using DRV8825

Edited 2 time(s). Last edit at 06/01/2015 11:53AM by XYZM.
Re: Power Supply Issue? Motors only studder when Extruder and Heat bed are on
June 02, 2015 07:02PM
Video so you can visually see


[www.youtube.com]
Where did you get those Vref numbers from? What current ratings are your motors? Current limit on polulu DRV8825 drivers is 2x the Vref, which would be very high with your settings, 3 to 4A. The drivers won't supply that and will shut down from thermal overload.
Vref is from the adjustment pot, and black on ground..

Motor current rating is 1.5A Model: 42SHD0217-24B


Similar to this guy

[www.geeetech.com]


He supplied .8 V to the X and Y and 1.8 V to the Z
Re: Video Update! Power Supply Issue? Motors only studder when Extruder and Heat bed are on
June 03, 2015 03:13AM
If you are in the US, check what mains voltage your PSU is set to. Someone else reported similar problems, turned out the switch on his PSU was set for 230V mains.



Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].
Re: Power Supply Issue? Motors only studder when Extruder and Heat bed are on
June 03, 2015 03:49AM
If you have experience with RC-LiPo batteries and have a 3s-pack at hand, you can help yourself until the replacement part arrives.

Follow at yout own risk, LiPo┬┤s can be dangerous when overcharged.
-Olaf
I would have to check the mains. I assume I put the multimeter on ground and live, or should I test the end that goes to the board...

There is a screw on my power suppl, near the connections.., any idea what this adjusts?
Quote
XYZM
Vref is from the adjustment pot, and black on ground..

Motor current rating is 1.5A Model: 42SHD0217-24B

So don't exceed 0.75 V for X & Y, and probably less for E, depending on if you have the same or smaller motor there. I'd recommend setting 0.5V for X,Y & Z and seeing if that helps. That will give 1A output which the 8825s can handle without a heatsink, running about 35 degrees in 18 degree ambient.

Quote

There is a screw on my power suppl, near the connections.., any idea what this adjusts?

Vout of the power supply. Some people crank it up to speed up their heat-bed warm-up times. I'd recommend setting it dead on 12V until you have everything else working properly.
Re: Video Update! Power Supply Issue? Motors only studder when Extruder and Heat bed are on
June 03, 2015 12:37PM
Quote
XYZM
I would have to check the mains. I assume I put the multimeter on ground and live, or should I test the end that goes to the board...

No, what I meant is that if the PSU has a switch to select the input voltage, make sure it is set for the mains voltage where you live. The switch is typically accessed through a cutout in the side of the metal enclosure. Do not adjust the switch with mains power connected, and do not set it to 110V if your mains is 220V.

Quote
XYZM
There is a screw on my power suppl, near the connections.., any idea what this adjusts?

You are probably referring to the screw that adjusts the output voltage. But that is unlikely to help you, because your problem appears to be that the output voltage is dropping under load.



Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].
Oh yes I live in the US, I am set to 220V
Re: Video Update! Power Supply Issue? Motors only studder when Extruder and Heat bed are on
June 03, 2015 02:15PM
Quote
XYZM
Oh yes I live in the US, I am set to 220V

Then you need to disconnect the PSU from the mains, wait a while (I suggest at least 10 minutes), then move the switch to the 110V position.



Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].
ahhh

On the side of the power supply it says

"110-120v 50 Hz"

"220-240v 60Hz"

I know we are on 60hz so I left it as it was.
Re: Video Update! Power Supply Issue? Motors only studder when Extruder and Heat bed are on
June 03, 2015 02:25PM
Quote
XYZM
ahhh

On the side of the power supply it says

"110-120v 50 Hz"

"220-240v 60Hz"

I know we are on 60hz so I left it as it was.

Looks like they got the 50Hz and 60Hz the wrong way round. There are no countries with a 60Hz 220-240V mains that I know of.

These PSUs are not significantly sensitive to the difference between 50Hz and 60Hz, however they are very sensitive to the difference between 110V and 220V. If you have it set to 220V and you give it 110V, you will get low output voltage and poor regulation - hence the symptoms you are experiencing. OTOH if you have it set to 110V and you give it 220V, you will blow it up.

So in a 110V country, the 110-120V setting is safe to use, and the correct one.



Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].
Thank you for the realization!

Settings my Drv8825 to around .5 V each

Ill see what happens.
Yep that was the issue...

Wow what a newbie mistakethumbs down..and my dad is an electrician....


Cheers smileys with beer
Quote

Then you need to disconnect the PSU from the mains, wait a while (I suggest at least 10 minutes), then move the switch to the 110V position.

Or just switch it immediately. There is absolutely nothing in a switching supply to merit a wait, and the 12v will be gone in 5 to 10 seconds if connected to the printer anyhow. In this case, since no output wiring is being worked on, that is irrelevant as well . . .

- Tim

Edited 3 time(s). Last edit at 06/03/2015 05:53PM by tadawson.
Re: Video Update! Power Supply Issue? Motors only studder when Extruder and Heat bed are on
June 03, 2015 06:08PM
Quote
tadawson
Quote

Then you need to disconnect the PSU from the mains, wait a while (I suggest at least 10 minutes), then move the switch to the 110V position.

Or just switch it immediately. There is absolutely nothing in a switching supply to merit a wait, and the 12v will be gone in 5 to 10 seconds if connected to the printer anyhow. In this case, since no output wiring is being worked on, that is irrelevant as well . . .

- Tim

I was more concerned about the charge stored on the high voltage capacitors that smooth the rectified mains voltage.. Not all PSUs have bleeder resistors or other mechanisms to ensure that they get discharged, and the 110V/220V switch is usually connected directly to them.

Edited 1 time(s). Last edit at 06/03/2015 06:08PM by dc42.



Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].
Worth upgrading to a better power supply anyhow. The stock convection - cooled Geeetech is only good for 150w(?) and the almost-equivalent printer from Folger Tech uses a 350W fan-cooled model. Even a cheap Chinese 12v LED 350W SMPS will be more reliable in the long term, especially if you plan to do long print runs (the large available print volume is very attractive smiling smiley !!)
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