HMS 0300-0100-0001-000E: supply voltage does not match, heatbed disabled
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HMS 0300-0100-0001-000E means the printer measured its incoming supply voltage, decided it does not match what this machine expects, and switched the heated bed off. That is a deliberate protection rather than a breakage. The bed is the largest mains load in the printer, and running it on the wrong supply is the one mistake with a real fire risk behind it.
Affected machines: A2L and H2D. Bambu ships machines configured for a mains region, and the bed heater is where that configuration matters most. This code appears most often after a machine has moved country, been bought grey-import, or been plugged into a generator or a cheap inverter.
Where to buy
Three things that produce this code
A genuinely wrong supply. A 110 V machine on 230 V, or the reverse. This is the case the protection exists for, and running the printer at all is the wrong move until it is resolved.
An unstable supply. A long extension lead, a shared circuit with a heavy load, or an inverter producing a modified sine wave. The printer sees the voltage sag when the bed switches on and reads that as a mismatch.
A measurement fault. The board that senses supply voltage has failed, and the supply is fine. This is the least common of the three and the only one that is a repair rather than an installation problem.
Heatbed will not heat and the printer reports a supply voltage mismatch
Wrong mains voltage, an unstable or shared supply, or a failed sensing circuit
- Unplug the printer at the wall before doing anything else.
- Check the machine’s rated voltage on its label and compare it with your mains. This is the first and most important step.
- If the machine is a grey import or has crossed a border, stop here and confirm the model is correct for your country.
- Plug the printer directly into a wall socket rather than an extension lead, a power strip or an inverter.
- Measure the socket with a meter while another appliance is running, so you see the voltage under load rather than at rest.
- If the supply is correct, stable and directly connected, and the code persists, record it and raise a support ticket.
Do not look for a firmware setting to override this. There is no version of running a bed heater on the wrong mains that ends well, and the protection is the only thing standing between a mismatch and a real hazard.
The control-side fault on the same bed is heatbed control abnormal, and the sensor version is heatbed sensor open circuit. Our page on bed temperature covers what the bed does, and the troubleshooting index covers the rest.
HMS 0300-0100-0001-000E FAQ
Can I print without the bed?
Not usefully. Nothing sticks to a cold plate reliably, and the code will not clear.
Could an extension lead cause this?
Yes. A long or thin lead sags under the bed heater’s load, and the printer reads that sag as a mismatch.
Is it safe to run the printer on a generator?
Only a pure sine wave one with headroom. Modified sine wave inverters commonly trigger this code.
My voltage is correct. What now?
Plug directly into a wall socket and retry. If it still fails, the sensing circuit is the suspect and that is a service item.
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