Connection problems
When Beam Bench cannot talk to your machine, or the connection is unreliable.
Anything between Beam Bench and your machine: cables, drivers, ports, baud rates, ground loops. Most connection problems are one of a few common causes.
Pages in this section
- Machine will not connect: you click Connect and nothing happens.
- GRBL error codes: what
error:Nandalarm:Nmean. - Port is not listed: the serial port for your machine does not appear in the dropdown.
- Disconnects mid-job: connection drops while the laser is running.
- Baud rate mismatch: garbled responses, no response, no welcome message.
Quick diagnostic flow
- Is the port listed? No → Port is not listed. Yes → continue.
- Does Connect succeed? No → Machine will not connect.
- Is there a welcome message in the Console? No, but seeing characters → Baud rate mismatch.
- Does it stay connected? No → Disconnects mid-job.
- Got an
error:Noralarm:N? → GRBL error codes.
Open the Connection Diagnostics panel for live visibility into what is happening.