Thanks for the response neotko. Every bit helps.
The circuitry for the heated bed and for each of the two nozzle heater circuits is identical. I looked at the actual traces inside and on the board and the mosfet switches are also identical. The heated bed is I believe about 100W or about 4 amps. So I don't think you should go over 4 amps. But you are talking about <4 amps so the electronics will be fine - it's just the power supply that you need to increase. Also if you don't use the heated bed and the nozzle at the same time it should also be fine. So for example if you are only heating the bed to 60C then I think the supply might be okay as is as long as you don't heat the nozzle until the bed is completely warmed up.
Also note that there is a firmware setting where you can limit power to the nozzle. For example you can say 50% power (128) is max power to ever apply to the nozzle. This will be pulsed but the power supply can go FAR over it's normal limit during the pulses and will be fine as long as total power draw doesn't exceed it's spec for a longer duration e.g. 1 second.
@coen? Is that correct? heated bed about 4 amps?
- 1
Thanks for the response gr5. Every bit helps. The hot plate has 7.5amps printed on it but I measured it with a fluke clamp meter at 6.5amps during its operation.
To answer neotko's "What hot end is that".
They 're part of the Creatr 2X Dual extrusion kit. Almost identical dimensionally to the olssen block. Three holes in the back to accommodate 2 heating elements and 1 temp sensor. Slight offset on the screw that comes out the top of the block that enters the bottom plate. A new bottom plate ships with the kit.
These blocks heat up rapidly but because of the extra wire mass they cant be ran up through the center of the print head like the original equipment.
Clamp meter? An inductive meter? Inductive meters only work on 60Hz and sine waves. It will probably read a bit low because it's less than 60Hz but it will read extra high because it's a square wave. I think the square wave wins - it can't be 6.5 amps anyway that's crazy. Just measure the resistance when power is off - that won't change much when it's hot. Wattage = V ^2/R or current=V/R
My readings were taken with a Fluke 374 True RMS digital clamp meter. The 6.5 Amp reading was obtained in min/max mode and measures the current fluctuation then shows the minimum, average and maximum. 6.5 was the max.
This paragraph came from Fluke. Thanks for your response.
A more sophisticated true-rms meter can accurately measure both pure waves and the more complex nonsinusoidal waves. Waveforms can be distorted by nonlinear loads such as variable speed drives or computers. An averaging meter attempting to measure distorted waves can be up to 40% low or 10% high in its calculations.
The need for true-rms meters has grown as the possibility of nonsinusoidal waves in circuits has greatly increased in recent years. Some examples:
•Variable-speed motor drives
•Electronic ballasts
•Computers
•HVAC
•Solid-state environments
The 6.5 Amp reading was obtained in min/max mode and measures the current fluctuation then shows the minimum, average and maximum. 6.5 was the max.
Nice meter. Better than anything I have. Well the average is more important what was that? The power supply will deliver double rated power briefly but not continuously.
Hello gr5,
I don't have the information at the moment but I have another question.
I have a dual extrusion kit. The hotends are pulling over 3amp each(80+w). Cant print because the machine shuts down. I added up the max current draw of the head cooling fans, bed, 1 nozzle, LED's. The value exceeds my power supply. I measured the current draw of the stock nozzle heater block at 1.4amps(33.6w). Less than half the setup is trying to pull now.
Could the power shutdown be caused by power allocation within the firmware.
I'd recommend you use a different meter. I believe (could be wrong) that clamp meters tend to not read low currents very well. Or if you have spare wire to the circuit you want to measure, wrap as many turns as you can around the clamp. Then read the current and divide it by the number of turns. More is better, like 10 turns... That meter has a maximum current reading of 600A and you are trying to read current 2 orders of magnitude less.
Otherwise, measure the resistance of the heater when cold and when hot and we can calculate the current.
I don't own a UM with the new electronics so I'm not 100% sure but I believe that the electronics don't measure the power or current and can't turn off the printer. Again, I could be wrong here.
When you say "shuts down:, do you mean turns off completely? If so, it's the power supply's over current protection shutting the PS down, not the UM2 based electronics.
There appears to be a safety circuit that will cut off the 24V power but not the power to the electronics. This has something to do with J17 and J16. Looks like there must be continuity between both connectors to allow the 24V relay to switch on.
Here is a good reference for the board: https://github.com/Ultimaker/Ultimaker2/blob/master/1091_Main_board_v2.1.1_(x1)/Main%20Board%20V2.1.1.pdf
Hello anon4321,
Thanks for the response.
The power goes out then back on. When the power comes back its the same as when the machine is powered on from the off state. The Ultimaker greeting is displayed then the first menu.
The power brick itself is cutting power. It is very sophisticated - I assume it actually has it's own computer. It probably has both a temp sensor in it and a current meter but I have messed with these causing them to fail on purpose and they will go VERY FAR over their rated values. So the 221W supply will go to 250W for several minutes no problem (at least the one I tested does) and will put out 400W for a few milliseconds. When they cut out they only cut out for less then a second.
I suspect it actually trips on the voltage drop - when the output voltage gets down to around 23.5V or something like that it just shuts down and turns back on. This causes Marlin to reboot and not realize you were just in the middle of a print a second ago.
The more accurate way to measure the current is to put your meter in amps mode and measure the current going through the wires (put the meter into the circuit).
Or simply measure the resistance of the heated bed cold. It's not much different cold versus hot. current = 24V / R
Wattage = 24*24/R
When I did experiments I actually cut the power cable and inserted a high wattage, low resistance resistor in there and measured the voltage across this with an oscilloscope so I could see the exact current millisecond to millisecond.
Edited by GuestThanks gr5,
I was also wondering does the power supply send out a 5v and 24v or just 24v.
Just 24V. The board converts that to 5V in some places and I think also 12V. The schematics are all easy to read and open source pdf here:
Edited by GuestHello neotko,What'l hotend it's that?
I use a meanwell 280W model http://www.mouser.com/Search/m_ProductDetail.aspx?Mean-Well%2FGS280A24-C4P%2F&qs=b8LFrSqGEF9zAXdxwVL1Jw%3D%3D
The problem it's that you have to 'cut' the CP4 plug and replace it with the correct R7B. Anyhow I think there are many powerbricks that can provide more than 220W. The think that I don't know it's how many max amps can the board actually use without issues, but probably someone with more knowhow will answer you.
The link to the power source didn't work but I found this one on Amazon. Is this the one?
The model number fits. Mouser sells the parts to make a R7B connector. And I think there's some very old video of how to assemble it, but I don't remember where I found it... For mine I did killa powerbrick to cut/solder it fast since the x4 colored cables did match from one brick to the other and it been working for a year so far without issues.
Good think I always save this weird stuff XD
If you buy the R7B connector, the company that makes them has a video explaining how to assemble it right, because it has 7-8 parts and looks so weird I never did this, but I have it on a bag saved just in case I need to bring to life the original brick.
http://domino2.kycon.com/website/Tools/assemblyvideos.html
Check the KPPX assembly video
Thanks neotko
Recommended Posts
neotko 1,417
What'l hotend it's that?
I use a meanwell 280W model http://www.mouser.com/Search/m_ProductDetail.aspx?Mean-Well%2FGS280A24-C4P%2F&qs=b8LFrSqGEF9zAXdxwVL1Jw%3D%3D
The problem it's that you have to 'cut' the CP4 plug and replace it with the correct R7B. Anyhow I think there are many powerbricks that can provide more than 220W. The think that I don't know it's how many max amps can the board actually use without issues, but probably someone with more knowhow will answer you.
Edited by GuestLink to post
Share on other sites