Step 00a.12 — Decide now what you do when it smokes, trips or bites¶
Step 12 of 12 · Chapter 00a — Mains safety: read before Chapter 09
(no image — see text)
Parts: none.
Do: Agree these five responses before you need one. Every fix below is the branch an existing step already owns; none of them is improvised here.
Check
All five responses agreed out loud, the breaker labelled, and the extinguisher in reach of the machine rather than in a cupboard.
What you're looking at
No parts: five agreed responses. Each row's Do this first removes energy from the machine; the Then column points at the existing step that owns the diagnosis, so nothing here is improvised.
| What happens | Do this first | Then |
|---|---|---|
| Breaker or RCD trips the moment you switch on | Switch off at the wall, unplug, leave it off | RCD tripping is an L-or-N-to-earth fault; a breaker is L-to-N. Redo 10.18–10.19 |
| Smoke, a hot smell, buzzing or click-cycling | Switch off at the wall, not the rocker, and unplug | Do not open the bay until 10.73 reads 0 V held ten seconds. Suspect a strand outside a terminal, or the PSU selector (10.2, 10.22) |
| A temperature climbs with nothing commanded | Cut power at the switch | Ch 13's what-if table calls this a heater energised through a wiring fault — back to Ch 10, do not "just watch it" |
| SSR reads short LOAD 1 → LOAD 2 unpowered | Do not energise the machine | A solid-state relay that reads short is dead and the bed would be permanently live. Replace it (10.21, 10.78) |
| Someone is shocked or stuck to the machine | Do not touch them. Kill the circuit at the breaker you labelled in 00a.5 | Then emergency services. Any shock, however small, ends the session — the machine stays unplugged until the PE sweep at 10.77 has been redone |
Two standing rules on top of the table. Never re-energise a circuit that tripped without finding out why — a second trip is not new information and it is not a test. And keep the extinguisher from Step 13.1 permanently by the machine, not just on startup day: RepRap's position on unattended printing is that "No printer shall remain unattended", and this one runs multi-hour ASA prints in a hot chamber. No Voron or LDO source specifies an extinguisher class. Buy an ABC extinguisher: A covers burning plastic, C covers live electrical equipment (NFPA 10 classes). Check the label shows the C before it goes by the machine.
Good stopping point · ~25 min since the last one
the chapter is read and nothing is half-done, because nothing was started. The only durable outputs are the posted room rule, the labelled breaker, a tested meter and five agreed responses. Do not carry on into Ch 09 in the same session if you are tired; Ch 09 ends with the machine on its back and the bay open.
Source: RepRap — Safety · Ch 13 — What if · Ch 10 Steps 10.19, 10.21, 10.73