Quick Scoop

For a Fravol SMI corner rounding machine that won’t start , the first things to check are the power supply, emergency-stop circuit, overload protection, and any loose wiring or safety interlocks. Machines that “jitter” or try to move but don’t actually start often point to a motor-start or control-circuit problem rather than a purely mechanical one.

What to check first

  1. Power at the machine. Confirm the plug, breaker, fuse, and incoming voltage are good. A machine that has no response at all is often a simple supply issue.
  1. Emergency stop and safety switches. Make sure the E-stop is released and any guard or cover interlocks are closed properly; a failed interlock can block startup.
  1. Overload or thermal protection. If the machine recently stopped under load, let it cool and reset any overload device before trying again.
  1. Start capacitor or motor circuit. If the machine hums, jitters, or tries to start and fails, the start capacitor, relay, contactor, or motor winding may be at fault.
  1. Loose connections. Check for loose terminals, damaged cables, or corrosion in the control box and motor wiring.

Practical troubleshooting flow

  • Turn power off and isolate the machine before opening panels.
  • Check the breaker, fuse, and supply voltage.
  • Verify the E-stop and all safety switches are reset.
  • Reset overload protection if fitted.
  • Inspect wiring, terminals, and the motor starter components.
  • If it still only hums or jitters, suspect the capacitor, relay, or motor itself.

When it is likely a bigger fault

If the machine has correct power but still refuses to start, and especially if you hear buzzing, intermittent clicking, or see the motor twitch, the issue is more likely electrical than mechanical. A damaged control board, failed contactor, bad capacitor, or motor fault usually needs a technician with the proper test equipment.

Safety note

Do not bypass safety switches or keep cycling power if the motor is locking up or overheating. That can damage the machine further and create a shock or fire risk.

Clean version for a forum post

My Fravol SMI corner rounding machine will not start. I have checked the power supply, emergency stop, overload protection, and wiring, but it still won’t run. If anyone has seen a similar startup issue, especially a motor jitter or capacitor problem, I would appreciate advice.

TL;DR: start with power, E-stop, overload reset, and wiring; if it jitters or hums, look at the capacitor, contactor, relay, or motor.