I’ve noticed that majority of my LED bulbs are flickering when A1 is printing. It is barely noticeable, but once you see it you keep concentrating on it. House is ~15 years old, no issues with electricity. I found multiple users with similar issues on reddit, one of them mentioning:
The AC 220V electricity we have here in India switches at 50Hz and not 60Hz. So when the printer runs, some of the lights in the house flickers at the mismatched cycle time.
I’m in Europe, so 220V as well for me. User mentioned how he fixed this for other 3d printer brand:
All of my printers have a parameter (heater pwm_cycle_time) that I can set in the config to be 50Hz and all of the light flickering magically disappears.
Has this been addressed already? Is there any fix in place?
I am having the same issue as you. Also in Europe. My wife mentioned that this can be bad for sensitive electrical gear, so I would also like to know if and how this can be fixed.
It may (note - not always) reduce the emi by plugging in an old style transformer based psu, such as used for a 12v supply for battery chargers, whatever. It needs to feel heavy, not the light weight modern phone charger) plug it in next to the printer. The transformer may absorb enough of the emi to prevent the lamps flickering. Led lamps can be very sensitive, depending on their voltage dropping components. AFAIK, the bed switches at a frequency of 1Hz, but the bbl psu should not allow that to pass back into the house wiring. Not much help to you, but I do not get it impacting my LED lamps (50Hz, 240V)
Same here. Although I don’t notice it at all with my LED lights, my old fluorescent lights are flickering like crazy. I am also wary of using my printer, because this cannot be good for my other electronics.
Yeah, eagerly anticipating some feedback from Bambu Lab… Although, based on my experience with the support regarding missing glue stick in the package I’m not expecting much.
I’m currently testing different bulbs with moderate success. Replaced some of the bulbs with different brand and it seems like this helped, but I wouldn’t make any conclusions based on that yet. Will update you all in the next weeks.
I caught it on video, but unfortunately I cannot link to youtube.
This light in our house still has an old school bulb and it flickers noticeably. This stopped immediately once the print stopped, which does suggest that this has to do with the heating element, and not the stepper motors as they were still moving to back to home position.
The electrical spec on the X1C is (I realize this thread is about the A1)
100-240 VAC, 50/60 H, 1000W@220V, 350W@110V
On 220V the power pulled is about 3x what it pulls at 110V. (It would be 4x except for regulation) This is because the heaters pull more current and power at higher voltages so heat faster but put more load on the wiring. It will be similar on the A1. The powers will likely be a little different but the principle is the same.
The flickering isn’t a fault per se of the printers. It’s the wiring and electrical supply that isn’t up to all that current being pulled and the flickering is because of voltage drops caused by the high currents.
But on 220V that’s a big load - 1000W. It’s like a standard 1000W microwave which probably also causes lights to flicker (more an on/off as the microwaves cycle on and off) for those who have flickering from the printer. At least where I am, loads like microwaves get their own circuits but will be pulling more current for 1000W since they are 110V/120V here.
The issue is a regular resistive heater will pull twice the current at twice the voltage. That’s why the power demand is so high on higher mains voltage.
There is an easy fix but it’s around $50 to $100. There are 220V/110V step-up/step-down transformers available. Since the X1C on 110V is rated at 350W, a 1000W capable transformer should provide lots of headroom. The wattage will be basically the same on both sides (plus inefficiencies).
A 1000W rating Yinleader converter is $60 at Amazon. No idea how well made it is but using something like that for step-down will reduce the power load on 220V circuits. The down side is slower heating and possibly lower temperatures.
Added - was looking at sizing and they say for heater circuits you want 4 times the wattage rating which means 1400W in the X1C case or probably 1500W since 1400W ratings might not be available. A 1500W version is $70.
That’s not how a power supply works, or at least I really hope it isn’t on the Bambu
Watt (power) is a product of voltage and current, the resulting power should be pretty similar regardless of where you use it in the world. There is no reason why it should waste three times as much power in Europe compared to 110V countries. I think they just wrote the power specs in a super weird way.
Regarding bed heater cycle time, that does seem like a possible solution, but why then isn’t it running on a 50Hz cycle. The power grid in China is 50Hz too
I think the bed heating element is running at mains frequency and voltage. It is switched on and off, afaik, at 1Hz. If the printer is on the same circuit as LEDS, they may ‘see’ that change in the current through the wiring, depending on the gauge and length of wire, and the ‘quality’ of the electronics within the LED. A filament lamp may also see that, but not so obviously. In the UK, the lighting and power circuits are separated (or should be) so interference of this nature is less likely. If the heating element was switched at anything above 30Hz you most likely would not ‘see’ the effect on LEDs, whatever type of house-wiring or ‘quality’ of LED, or better still dc heating, switched at any frequency, where the load would hopefully be smoothed out via the ac/dc inverter. Do not expect BBL to correct any of this in existing models, and if house wiring and lighting is adequate, there is no need.
For individual cases, then as I mentioned earlier, there may be simple solutions. Basically, iron in the circuit can smooth things out. (In fact, any load on the circuit will most likely lessen the effect. More LED lights in this scenario, is not load - it needs to be few kilowatts.)
For resistive heaters it’s just Ohm’s law - V = I * R
Power is volts times current…. P = V * I
With resistive heaters, rearranging, current is volts divided by resistance… I = V / R
Resistance is fixed so power goes by the change in voltage squared.
P = V * V / R
Since voltage doubles from 110V to 220V, the power should go up by the square of the change in voltage. 2 * 2 = 4
But it doesn’t quite follow that. The printer goes from 350W at 110V to 1000W at 220V. If all that mattered was resistance, the power at 220V should be 350W * 4 or 1400W but it’s only 1000W.
That difference is regulation and how the value is calculated for the rating. I don’t know if that is peak or averaged but I’d bet averaged over some time period. Someone with a power meter on 220V could see what peak powers are.
But there are other issues - the electronics and motors are run from a power supply so with those, actual power demand may even go down at higher voltages because currents are lower so lower resistance losses at higher voltage but it would still be very close to the same powers on 110V and 220V.
The trick is the heaters. Bambu uses/switches line voltage on and off to drive the heaters. Those see the change in current at higher voltage just by Ohm’s law. The stuff that runs the motors and electronics are fed by power supply that has essentially constant outputs so as voltage goes up, current demand goes down. Depending on the power used in the two halves (resistive heaters vs electronics) that could also account for the 1000W vs 1400W discrepancy.
If the stuff about Ohm’s law doesn’t make sense, just put in dummy numbers and double the one you use for voltage.
It’s muddy, though. That’s the bit about how the power is measured for the rating. The thing is during heating from cold, the heaters will at first be on solid but later on 220V the heaters should be off a bigger percentage of time than 110V since the printers are regulating to the same temperatures. But during the main/first heating, and when the heaters are on, the current load for the heaters is double what the 110V powered printers see.
Ultimately, the power used to print a model will be very similar between the two voltages. It’s just when the heaters are on the power goes way up on 220V compared to 110V. On time for the 220V heaters will end up being lower than the 110V version. It’s a dynamic thing I’m probably not explaining well.
One clarification on that. The discussion is correct but I shouldn’t have used 350W as the base number to then multiply by 4. The reason is it is also a combination of electronics and heater loads. So the number that should be multiplied by 4 is less than 350W.
And it should be possible with a little math to solve for the partition between heaters and electronics and then solve for how much heater power when running from 110V and 220V.
But I was wrong to use the full 350W as resistive heater. That inflated the 220V number higher than it should have been.
Yeah, those should draw about the same power. It’s the resistive loads that spike the current and feeding those would have made the power supply much bigger if that power went through it.
But I’m sure the power used per model printed is about the same. It’s just the peak power when heaters are on is way different and the duty cycle on the heaters will be much lower on 220V.
Your idea of using a large stepdown converter is very interesting and if your theory holds true it should provide a much more even use of power from the bed heater.
I have asked a friend of mine if he has one I can borrow to test it. I believe he has some large ones he use to power his imported arcade cabinets. I will let you know if this works out
Please do! That would be extremely good to know how it goes since as you can see there’s lots with this issue. Just be sure it’s sized over or matches the guidelines for power capacity according to that company link I posted.
If you have a power meter like a Kill-A-Watt or similar - that can handle the load - it would be more good information.
