Machine Will Not Start: Diagnostic Sequence

Problem

Pressing start produces no motion. The HMI may show a safety or condition message, or the control cabinet may show no power at all.

Possible Causes

1. An emergency stop button is latched, or a guard/door interlock is open.
2. A previous alarm has not been reset.
3. Main disconnect or branch breaker is off, or a phase is lost.
4. Control voltage is absent — power supply or fuse issue.
5. A start-permissive condition (air pressure, temperature ready) is not met.

What to Check

• STEP 1Walk all E-stops and guards.Release every emergency stop along the line and confirm all guard doors and interlocks are fully closed and latched.
• STEP 2Read the HMI condition list.Resolve any outstanding alarm or start-permissive message; air pressure and sealing temperature readiness are common conditions.
• STEP 3Verify supply.Confirm the main disconnect is on and, where qualified personnel are available, that all phases are present at the machine inlet.
• STEP 4Check control voltage indicators.Compare the indicator state on the control cabinet against the machine manual's diagnostic table.
• STEP 5Restore permissive conditions.Bring air pressure and other conditions into range and confirm readiness indications return.

Corrective Actions

• Reset alarms only after their cause is understood and cleared.
• Restore air supply or other permissive conditions and confirm readiness indications.
• For any supply or control-voltage finding, stop and involve qualified electrical personnel — do not open cabinets without authorization.