Hi, im just order p1p and im read that most parts works on 24V DC, exept HotBed……
Anybody have any idea how to easy change hotbed for 24V DC ?
Why ? Because my printer will be in my server room where im have backup power supply based on 18650 that gives me 24V DC 500W power when im loose my main 230V……
I dont want use UPS because it loose a loot of power for transform 12V to 230, and then again in printer from 230 to 24….
The Bambu printers use a DC-AC SSR on the AC board, that’s controlled by the MC board. And the plate heater is setup to run at 120V AC, so its resistance would be too high to get much power at all from a 24V DC source. I don’t know what the heater’s resistance is, but just for example if it were a 300W heater at 120V, it would only be 12W at 24V. The power generated is (Voltage time Voltage) divided by Resistance, so the power with 24V across the heater will only be 4% of what it is at 120V.
That’s a bit of an oversimplification giving that the heater’s resistance will change as it heats up, but regardless the 24V supply wouldn’t generate enough heat at all.
And that’s just the first issue without digging into any modifications to the AC board and the DC-AC SSR.
UPDATED example of power derating: The bed power at 24V will be 1.09% of the bed power at 230V. So basically 1/92nd the power. Thanks @holmes4 for pointing out the OP was looking at 230V mains and not 120V.
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Minor correction - the bed runs at mains voltage, whether that be 110-120 or 220-240. If your mains voltage is in the 240V range, the bed will heat up much faster than on 120V but will also draw four times the power.
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My “live in the US plugged into residential 120V” got the better of me 
Couldn’t you just use a Sine Wave inverter ?
While the power is on (no outage)a trickle charger on a few dry cell batteries run in parallel with the inverter run off the batteries and your printer plugged into the inverter
Just a cheap Ebay inverter below but there are many brands and different qualities of inverters out there