Reduce bed electrical consumption

gionico · January 27, 2023, 12:49pm

I would like to understand if it is possible to implement an initial gcode that would choke the current absorption by the bad. During the heating of the bed we are at 1000watt absorption and my UPS is struggling. I don’t care if it would take longer to heat up, I just care about reducing the absorption

holmes4 · January 27, 2023, 6:16pm

The bed is fed directly from the AC mains and is not controllable other than on/off, as far as I can tell. You could do the opposite of what some in the US do and use a step-down transformer to 120V, this drops the power consumption of the bed by a lot. You’d need one capable of handling 500W.

Alkerion · September 20, 2023, 8:53pm

I think you use the wrong type of UPS, you must use an offline, not an online.

The major point that differentiates between the online UPS and offline UPS is that the online UPS supplies power from the AC mains to the Load through the rectifier and inverter combination while the Offline UPS directly supplies power from AC mains to the load.

I use an APC ES 550 for the Bambu, PC, monitor without any issues.

desmosa · December 19, 2023, 1:51pm

Hi there, do you already have the solution? I’m also currently facing the same issue, those initial 1000W load on 240V keeps tripping the breaker. I’m also thinking of using a stepdown transformer to 120V, so it will consume less power initially… Other choice is to use a huge power station.

lkraus · December 19, 2023, 10:26pm

1000 watts at 220 volts is only about 4.2 amps, which is not very much of a load. What else are you operating on that circuit, and what is the rating of the breaker?

sardelich · December 19, 2023, 11:16pm

on a standard 10A fuse, you can safely run 2 bambus on 220V. something is not good there, or you run extra devices together with printer. I run 4 P1S on 16A, only thing I need to watch is not 4 of them preheating at the same time. Once running, each eats up no more than 150W.

desmosa · December 20, 2023, 12:49am

I have several lines with 5A and 10A breakers (at 220V). Unfortunately all the lines are saturated and I can only probably run a maximum of 500-600W without tripping the breaker. I know it won’t be a problem once it’s running, but that 1000W initial load is guaranteed to trip the breaker. My previous Ender 3 S1 runs at 300W during preheating, and drops to 90W during printing, and that ran flawlessly.
I might have to rearrange some of the lines for now.

desmosa · December 20, 2023, 12:52am

Yeah, unfortunately all the lines in my house are being used with other devices such as refrigerators, A/C, etc. 500-600W of load is probably the max for each lines without tripping the breaker. It’s especially bad on my work room, since there’s only 1 line / breaker, and it’s used altogether with my PC, 2 monitors, speakers, A/C, and other small peripherals

angled6711 · April 17, 2024, 6:48am

Had similar issues, based on my observation, the bed doesn’t require a lot of power to maintain its temperature, it will only consume the maximum power during the heat-up process. So what I did was to limit its heat-up time by telling the printer to heat a 5C first and wait 15s before proceeding to the next 5C. If the printer is just heating a 5C, it won’t use 100% power due to the PID controller. This method seems to work for me.

Below are my changes to the Machine start G-code
Original Code

;===== heatbed preheat ====================
M1002 gcode_claim_action : 2
M140 S[bed_temperature_initial_layer_single] ;set bed temp
M190 S[bed_temperature_initial_layer_single] ;wait for bed temp

Modified Code

;===== heatbed preheat ====================
M1002 gcode_claim_action : 2
;M140 S[bed_temperature_initial_layer_single] ;set bed temp
;M190 S[bed_temperature_initial_layer_single] ;wait for bed temp

{if bed_temperature_initial_layer_single > 40}
M190 S40
G4 S15
{endif}
{if bed_temperature_initial_layer_single > 45}
M190 S45
G4 S15
{endif}
{if bed_temperature_initial_layer_single > 50}
M190 S50
G4 S15
{endif}
{if bed_temperature_initial_layer_single > 55}
M190 S55
G4 S15
{endif}
{if bed_temperature_initial_layer_single > 60}
M190 S60
G4 S15
{endif}
{if bed_temperature_initial_layer_single > 65}
M190 S65
G4 S15
{endif}
{if bed_temperature_initial_layer_single > 70}
M190 S70
G4 S15
{endif}
{if bed_temperature_initial_layer_single > 75}
M190 S75
G4 S15
{endif}
{if bed_temperature_initial_layer_single > 80}
M190 S80
G4 S15
{endif}
{if bed_temperature_initial_layer_single > 85}
M190 S85
G4 S15
{endif}
{if bed_temperature_initial_layer_single > 90}
M190 S90
G4 S15
{endif}
{if bed_temperature_initial_layer_single > 95}
M190 S95
G4 S15
{endif}

M140 S[bed_temperature_initial_layer_single] ;set bed temp
M190 S[bed_temperature_initial_layer_single] ;wait for bed temp

user_3533789062 · November 27, 2024, 12:47am

does not work… it first pre-heat as expected, but then just stuck and do nothing, and bed start cooling

user_3533789062 · November 27, 2024, 1:39am

during “downloading”, printer on it’s own start heat bed to target temperature, and only than execute
{if bed_temperature_initial_layer_single > 40}
M190 S40
G4 S15
{endif}

so it just wait while bed from 75C cool down to 10C, to start slow heat …

user_3533789062 · November 27, 2024, 1:41am

user_3533789062 · November 27, 2024, 1:44am

github.com/bambulab/BambuStudio

Max. Bed Temperature is FORCED upon Print Start on Newest Firmwares (P1P)

opened 09:21AM - 19 May 24 UTC

bolsoncerrado

bug Printer

### Bambu Studio Version 1.9.1.67 ### Where is the application from? Ba…mbu Lab Official website ### OS version MacOS Sonoma 14.4.1 ### Additional system information M1Ultra ### Printer P1P ### How to reproduce 1. Define Machine GCode Preheating scheme to avoid UPS overload 2. Define Max. Bed temp for filament to 55, 60 or whatever 3. Launch a print with that filament and machine selected ### Actual results Upon launching the print, loading the gcode on the printer and "starting" to read the .gcode, printer sets the bed preheat temp to its maximum automatically. THEN after it has been reached, it starts reading the MACHINE DEFINED .gcode ### Expected results To just read the machine defined gcode in regards to bed temp gcodes. ### Project file & Debug log uploads The explanation is simple: I run a farm of MANY P1Ps. Every 2 P1Ps are hooked to a UPS supply. IF one or more printjobs are sent to P1Ps with the latest firmware on the same UPS, the printers try to PREHEAT the bed to its maximum first, THEN read the gcode. On previous firmwares this wasn't happening, the printer just read the gcode and used MY altered gcode to preheat the bed SLOWLY so the UPSs don't fail with an OVERLOAD alarm that requires me to phyiscally reset each UPS. The result is I have to keep my P1Ps on firmware 1.4.x for this NOT to happen. This is the GCODE I was using and that now is read AFTER the max heatbed temp is reached, which renders it USELESS because the OVERLOAD on the UPS are triggered :'( ----------------- M140 S10 M190 S10 M140 S15 M190 S15 M140 S20 M190 S20 M140 S25 M190 S25 M140 S30 M190 S30 M140 S35 M190 S35 M140 S40 M190 S40 M140 S45 M190 S45 M140 S50 M190 S50 M140 S[bed_temperature_initial_layer_single] ;set bed temp M190 S[bed_temperature_initial_layer_single] ;wait for bed temp ------------------- (I tried to use your logical operators IF THEN ELSE but they were not working fine for me for whatever reason). I hope this makes any sense and I still wonder WHY did you introduced such change of forcing the max bed temp and THEN read the machine gcode rendering it useless. I'm open to your questions! ### Checklist of files to include - [ ] Log file - [ ] Project file

user_3533789062 · November 27, 2024, 9:50pm

;===== heatbed preheat ====================
M1002 gcode_claim_action : 2
;M140 S[bed_temperature_initial_layer_single] ;set bed temp
;M190 S[bed_temperature_initial_layer_single] ;wait for bed temp

{if bed_temperature[current_extruder] > 15}
M140 S15
G4 S10
{endif}
{if bed_temperature[current_extruder] > 17}
M140 S17
G4 S10
{endif}
{if bed_temperature[current_extruder] > 19}
M140 S19
G4 S10
{endif}
{if bed_temperature[current_extruder] > 21}
M140 S21
G4 S10
{endif}
{if bed_temperature[current_extruder] > 23}
M140 S23
G4 S10
{endif}
{if bed_temperature[current_extruder] > 25}
M140 S25
G4 S10
{endif}
{if bed_temperature[current_extruder] > 27}
M140 S27
G4 S10
{endif}
{if bed_temperature[current_extruder] > 29}
M140 S29
G4 S10
{endif}
{if bed_temperature[current_extruder] > 31}
M140 S31
G4 S10
{endif}
{if bed_temperature[current_extruder] > 33}
M140 S33
G4 S10
{endif}
{if bed_temperature[current_extruder] > 35}
M140 S35
G4 S10
{endif}
{if bed_temperature[current_extruder] > 37}
M140 S37
G4 S10
{endif}
{if bed_temperature[current_extruder] > 39}
M140 S39
G4 S10
{endif}
{if bed_temperature[current_extruder] > 41}
M140 S41
G4 S10
{endif}
{if bed_temperature[current_extruder] > 43}
M140 S43
G4 S10
{endif}
{if bed_temperature[current_extruder] > 45}
M140 S45
G4 S10
{endif}
{if bed_temperature[current_extruder] > 47}
M140 S47
G4 S10
{endif}
{if bed_temperature[current_extruder] > 49}
M140 S49
G4 S10
{endif}
{if bed_temperature[current_extruder] > 51}
M140 S51
G4 S10
{endif}
{if bed_temperature[current_extruder] > 53}
M140 S53
G4 S10
{endif}
{if bed_temperature[current_extruder] > 55}
M140 S55
G4 S10
{endif}
{if bed_temperature[current_extruder] > 57}
M140 S57
G4 S10
{endif}
{if bed_temperature[current_extruder] > 59}
M140 S59
G4 S10
{endif}
{if bed_temperature[current_extruder] > 61}
M140 S61
G4 S10
{endif}
{if bed_temperature[current_extruder] > 63}
M140 S63
G4 S10
{endif}
{if bed_temperature[current_extruder] > 65}
M140 S65
G4 S10
{endif}
{if bed_temperature[current_extruder] > 67}
M140 S67
G4 S10
{endif}
{if bed_temperature[current_extruder] > 69}
M140 S69
G4 S10
{endif}
{if bed_temperature[current_extruder] > 71}
M140 S71
G4 S10
{endif}
{if bed_temperature[current_extruder] > 73}
M140 S73
G4 S10
{endif}
{if bed_temperature[current_extruder] > 75}
M140 S75
G4 S10
{endif}
{if bed_temperature[current_extruder] > 77}
M140 S77
G4 S10
{endif}
{if bed_temperature[current_extruder] > 79}
M140 S79
G4 S10
{endif}
{if bed_temperature[current_extruder] > 81}
M140 S81
G4 S10
{endif}
{if bed_temperature[current_extruder] > 83}
M140 S83
G4 S10
{endif}
{if bed_temperature[current_extruder] > 85}
M140 S85
G4 S10
{endif}
{if bed_temperature[current_extruder] > 87}
M140 S87
G4 S10
{endif}
{if bed_temperature[current_extruder] > 89}
M140 S89
G4 S10
{endif}
{if bed_temperature[current_extruder] > 91}
M140 S91
G4 S10
{endif}
{if bed_temperature[current_extruder] > 93}
M140 S93
G4 S10
{endif}
{if bed_temperature[current_extruder] > 95}
M140 S95
G4 S10
{endif}
{if bed_temperature[current_extruder] > 97}
M140 S97
G4 S10
{endif}

M140 S{bed_temperature[current_extruder]}
M190 S{bed_temperature[current_extruder]}; ensure bed temp

sardelich · December 13, 2024, 4:55am

quite normal.why wait when you can heat up and download

user_3533789062 · December 14, 2024, 6:30pm

i have online ups 1 000 watts, and it starts struggling when printer heating like kettle
some people have only 6A in power supply, so just because of insane unnecessary fast heating, them can’t use printer
people which have farm from P1S, let say 4 printers, have to have UPD 1.5 kW * 4 = 6 kW ups, otherwise from time to time printers heats simultaneously and all screwup, even worse, 6kW is too much for regular electrical outlet
if i programmatically change behavior, printer shouldn’t do anything else

sardelich · January 7, 2025, 4:07am

some like speed. I like to get to the temp fast.