Is there a difference in using a 12V or 24V for the Jackpot Controller board?
Does one power supply have an advantage over the other or does it remain the same which one I use? My controller board will arrive one of these days. Currently I use a 12V for my SKR board.
24V has a higher speed/power threshold. It does make a noticeable difference, not a huge one but noticeable enough to where I feel the price is easily justifiable.
Thx.
I will order a 24V power supply. What is the minimum ampere that it must be able to supply for a Lowrider ?
2.5A+
Can you elaborate on this âhigher speed/powerâ statement? How does that translate to the operation of the machine itself? Iâm looking at the 12v 6A power supply from the MPCNC right now. I imagine Iâve got a 24V PS here somewhere too.
At 24V, IR drops all through the system are lessened. There is less losses in the wiring, so youâre better able to deliver power (torque) at the steppers. Good modern steppers like the TMC2209s are particularly good at delivering this additional power through the system.
Itâs not an overwhelming benefit to the point where using a beefy 12V power supply doesnât make sense. Especially if you already have a good 12V PS, that might be fine.
The other thing that might sway you is whether you have anything in the system where you want to drive it with the MOSFETs, as those are VMOT switched power.
So, for example, if you had a 12V solenoid for turning on/off a mister or air pump then running 24V is more work as you would need to add accommodations for that.
Same for if you had a 24V accessory but wanted to use 12V for your board for some reason (Like having other accessories that are 12V power)
Everything is always a trade.
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The limits of my power supply knowledge (can you call it that?) comes from my Christmas lights. If they are 5v LEDs you need a 5v power supply, if they are 12v, you need 12v.
In my box of power supplies Iâve got the one above from the MPCNC (12v). Iâve also got several 12V Meanwells ranging anywhere from 30A-60A. For wall warts/bricks I have the following:
15v 4a
18v 2.5a
19.5v 3.34a
19.5v 4.62a
Are any of the non-12/24v options viable or am I better off getting my hands on a 24v power supply?
Those with above 4A might be usable depending on the specifics. Some laptop bricks have a communications protocol where they wonât work right unless connected to their intended target devices.
What might make your decision is the packaging of the PS. In the really cold environment, a sealed power supply might make much more sense than an open frame power supply.
The higher voltages can support longer wire runs so that might be something to consider also.
All of the voltages you list will work with a jackpot that has no MOSFET accessories to worry about.
The 18V 2.5A supply might be a little bit on the weak side for your application.
I appreciate the wisdom. I went ahead and ordered a 24v, 6A brick just to be sure. At the very least itâll keep âapples applesâ if I need help from the collective here in troubleshooting. It will be here tomorrow afternoon which will force me to take care of other things that Iâve been very effectively procrastinating.
At slower speeds. The 12V works identical to a 24V. The drivers are constant current power supplies to the steppers, not constant voltage. The drivers connect the power supply to the motors until they reach the current set point for each coil. A 12V PSU connected for 4% of the time or a 24V PSU connected for 2% of the time is essentially the same for everything.
Where the 24V matters is when the 12V reaches 100% duty cycle, which is when the steppers are rotating fast (steppers generate back emf and resist the voltage when rotating). Above that speed the 12V canât push enough current and the 24V can. So the 24V has more power when the steppers are rotating very fast. The 12V still works in this scenario, but it is like having a lower current set point and it could more easily skip steps.
The exact cutoff point where that happens depends on the size and length of wiring and the exact steppers. IMHO, most CNC builds wonât ever care. A corexy printer going 300mm/s will care, but not our lumberjacks moving at 20mm/s.
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Thatâs not my understanding of how modern stealth stepper drivers work. Yes, they shoot for a constant hold torque (current), but they do fancy peak/hold current delivery when commanding motion. If you look at them on a scope the waveforms look very different than an old style stepper driver. Particularly as you note at higher motion speeds.
Time for me to take another good look at the TMC2209 data sheet.
Edit:
I suppose when taking all the factors into consideration, weâre essentially saying the same thing.
I have been treating them just like this, MPCNC: 12 V Supply vs. Stepper Current vs. Axis Speed â The Smell of Molten Projects in the Morning If that is different for the TMCâs let me know so we can figure out how to get the best bang for the buck system.
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