As you might be aware BambuLab issued a recall for the BambuLab A1 3d-printer. In particular, the issue is the mains-voltage (230V AC) heat bed cable.
As a resolution, they offer two solutions:
- Ship the entire printer back to them and receive a replacement printer.
- They mail a new cable and you install it.
What BambuLab doesn’t mention at all is the test according to EN 50678 (Verification of the effectiveness of protective measures of electrical equipment after repair). Unless you can perform this test I would recommend choosing the printer replacement.
How so? There are a number of other printers that also use mains voltage to heat the bed without issue. As your bed size and thickness grows, running stepped down DC makes less and less sense.
Unless the heated bed is UL listed, I wouldn’t trust a live high voltage heater in my house. And I might not touch it unless the printer is unplugged.
They already undersized the wires to save money. Not a great start to gaining trust for a high voltage device.