When I got my P2S up and running i noticed two things right away. Plugging it into the same UPS and wall outlet of the P1S it replaced, the lights in the room have a notable flicker when this the P2S starts up and that lasts for several minutes. Also, the backup UPS screams that the current load is overloaded. The numbers speak for themselves. The P2S draws three times the power as the P1S as shown in the images. My choices now are to get a new UPS for the printer as it exceeds the 600W cap or remove it from the UPS. Also, I may need a new circuit for the light issues. This was not an issue with the P1S and I am hoping BBL comes out with a software fix for this since it only happens for the first 10-20 seconds it wakes after sending the print file.
I’m going to wager that you have LED light bulbs in your room. The flickering can be caused simply by uneven power draw on the circuit. Many LED lights don’t like it. I have Keurig in my kitchen which does not draw a lot of power yet, when I replaced the overhead light with a generic brand, every time I brewed a cup of coffee it would make the lights flicker. I replaced that bulb again but this time with a bulb from Amazon that says “flicker free” and the problem went away.
You are correct. I have 8 LED tubes in my shop. The P1S never caused even in minor flicker. The P2S not only causes flickers, but pulls over 3 times the current and makes my UPS go into overload and it’s the only thing connected to it. There is no reason for this to pull over 8 amps at start up when the P1S barely gets to 2.5.
Remember nothing is happening during those first 20 seconds so there is no reason for this to happen. Even when it’s printing the P2S only draws 3 amps max. So why the spike? I am hoping a firmware update may help, but BBL is taking days to respond.
Thanks for your response. Yes, 120V. I agree the bed may be starting to warm up. But the second I send the print job my UPS starts howling with an alert sound for overload. After taking the UPS out of the loop I measured the wattage draw and was shocked by the difference
I assume that the P1S does the same thing the P2s does at start up. But as I have shown, it draws three times the current at almost 1kw. This only happens for the first 20 seconds or so and there is no way the bed gets to temp in that amount of time. 8.3 amps at startup just doesn’t seem right to me.
I know this will not help, but looking at the specs sheet, indeed the P1S is rated as using only 350 W @120 V (it uses 1000 W on 220 V and heats up faster) - this seems to have changed for the P2S, where it now uses similar power for 120 V and 220 V. Perhaps they could include a slow-heatup feature…
Actually this does help. At least there is some documentation that supports my findings. However it still makes no sense to surge 1kw for 20 seconds at wake up when the sustained printing wattage on both machines is the same. I will see what they say and report back. If anyone knows why they do this I’d like to know. Thanks.
I tried searching for the earlier thread about this same topic on the X1 and P1 when they first came out, but I can’t find it. If anyone remembers it and can locate it more easily than I can, please link it here.
The original discussion focused on a firmware behavior in 2023 (v1.03) where the printer appeared to heat the bed and nozzle sequentially instead of simultaneously. The OP argued that this added unnecessary warm-up time. Another member suggested it was probably intentional to avoid overloading the power supply with both heaters running at once. The thread never reached a firm conclusion, and it was mostly speculation.
For anyone with a P2, can you check whether the bed and nozzle now heat simultaneously? Perhaps this might explain the 1KW power draw on startup. Another test would be to try pre-heating the bed and then starting the print just to see what the differential power draw is after the bed was already at temperature.
The power of the nozzle heater is almost negligible compared to the bed. The nozzle draws somewhere between 40 and 60W, right?
I think, they simply changed the bed heater in the 120V version to allow the same fast heatup times that were previously reserved to the 230V machines.
That is very unlikely as cause: The bed heater is not powered by the power supply but directly from mains. All modern printers have switched to a mains powered bed heater, because it allows those much faster heatup times.
Wow. Thats an impressive app you have. What are you using to track your appliances?
Also, that’s a huge starting spike for any printer. The P1S is 1/4 of that and I cannot tell any difference in staring. print times, or running current between the two machines. I wonder what they changed and why?
I use Home Assistant for my home and use some Shellys to track individual “high-power” devices like home network, coffee machine and now my P2S printer.
At the risk of hijacking my own thread, I have been heavily invested in SmartThings since v1, they are on V4 now. However V4 no longer has z-wave support, so that’s not an option for me. I am looking to start my journey to home assistant via a raspberry pi 5 running on an NVME drive. I have so many devices that it will take a very long time to rebuilt my smarthome, but it will eventually be necessary. Feel free to PM me with any thoughts on the conversion.
As for the power draw, ill stick by my guns. Since the surge above 8.3 amps is for less than 20 seconds on startup, they can change this in the firmware. Or they have to give me a valid reason for it, although I’d still be skeptical because nothing heats up in 20 less than seconds. some times the surge is less than 5 seconds.
You probably are right that this surge could be avoided by software. But I fear that this will not happen. Either there is an actual reason for the surge, but even if not, why should they change it? It is well within their spec, so they will tell you that it is working as expected. You say that they have to give you a reason, but they probably don’t agree.
So I think, if you want to keep using the printer, you will somehow have to arrange with this surge. BambuLab will not change it for you.
I was never under the illusion that BBL would do anything for me, or anyone else for that matter. Their support has been dismal.
I was just suggesting they should update the firmware if the spike was of no use. Do I think they will do it? I highly doubt it. But if enough people complain, especially if guys with multiple P2Ss are popping circuit breakers, perhaps they will listen.
Based on this new surge, you could not run more than two printers in a single 15a circuit as opposed to four P1Ss. That would be a huge cost difference for a printer farm buildout.
A lot of other mfrs have a “soft start” optional mode, so maybe Bambu will do the same. A huge zap of heat to start a cold bed warming is awesome imo but yeah can stress a stressed circuit. Assuming that’s what it is doing.
I don’t see what the surge is doing. I ran a print job on both. I used all the same setting and the same filament. The jobs finished within seconds of each other. So whatever the surge does, it’s no speeding up printing in any way I could see.
My house is only 4 years old so the electrical is all new. The only reason I noticed the surge is because the lights flicker noticeably when the P2S printer starts. No issues with the P1s. Thanks.
Here is the BBL official response. There is nothing here I didn’t already know, and unfortunately as i guessed, no action will be taken. I sent them two video clips in answer to their response that clearly show the difference. 1000w vs 375w at startup for printers with no difference in print times or functionality that i can perceive. It seems a minor firmware tweak would correct the start surge as it evidently makes no discernible difference.
As I side note, I purchased my UPS battery backup specifically for the P1S. Their suggestion is to up upgrade that as well for the P2S, which will cost another $300.00 US.The just increased my upgrade cost 35%, and I am not too happy about that.
Dear Customer,
Thank you for your contact.
The power consumption of the P2S is normal and may be higher than that of the P1S due to its higher performance and functionality. Here are some factors to consider:
Power Specifications :
The P2S has a maximum power consumption of 1200 W @ 220 V or 1000 W @ 110 V, while the P1S has a maximum power consumption of 1000 W @ 220 V or 350 W @ 110 V .
The power consumption may vary depending on the printer’s operation mode, such as printing, heating, or standby.
Heating Components :
The P2S may have more powerful heating components, such as a higher - wattage nozzle or a larger heatbed, which can draw more current during the heating process.
Additional Features :
The P2S is an upgraded version of the P1S and may have additional features, such as a higher - resolution camera, a larger touch screen, or a more advanced motion control system, which can increase the power consumption.
Power Surge at Startup :
When the printer starts up, there may be a power surge as the heating components and motors are initialized. This surge can be higher than the steady - state power consumption.
To avoid overloading your power supply or UPS, you can consider the following solutions:
Use a Dedicated Circuit :
Connect the P2S to a dedicated wall socket or circuit to ensure that it has sufficient power and does not interfere with other electrical devices.
Upgrade Your UPS :
If you need to use a UPS, choose a model with a higher power capacity to support the P2S.
Reduce Power Consumption :
You can reduce the power consumption by adjusting the printer’s settings, such as reducing the nozzle temperature or using a lower - power filament.
